State Street Institutional Investment Trust

As filed with the U.S. Securities and Exchange Commission on April 28, 2022

1933 Act File No. 333‑30810

1940 Act File No. 811‑09819

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM N-1A

REGISTRATION STATEMENT

UNDER


		THE SECURITIES ACT OF 1933		☒
		Post-Effective Amendment No. 294		☒

and

REGISTRATION STATEMENT

UNDER


		THE INVESTMENT COMPANY ACT OF 1940		☒
		Amendment No. 296		☒

STATE STREET INSTITUTIONAL INVESTMENT TRUST

One Iron Street,

Boston, Massachusetts 02210

(Address of Principal Executive Offices)

(617) 664‑1465

(Registrant’s Telephone Number)

Sean O’Malley, Esq.

Senior Vice President and Deputy General Counsel

c/o SSGA Funds Management, Inc.

One Iron Street

Boston, Massachusetts 02210

(Name and Address of Agent for Service)

Copy to:

Timothy W. Diggins, Esq.

Ropes & Gray LLP

Prudential Tower, 800 Boylston Street

Boston, Massachusetts 02199-3600

It is proposed that this filing will become effective (check appropriate box):

☐	Immediately upon filing pursuant to paragraph (b)

☒	On April 30, 2022 pursuant to paragraph (b)

☐	60 days after filing pursuant to paragraph (a)(1)

☐	On (date) pursuant to paragraph (a)(1) of Rule 485.

☐	75 days after filing pursuant to paragraph (a)(2)

☐	On (date) pursuant to paragraph (a)(2) of Rule 485.

If appropriate, check the following box:

☐	This post-effective amendment designates a new effective date for a previously filed post-effective amendment.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Aggregate Bond Index Fund

Class A (SSFCX) Class I (SSFDX) Class K (SSFEX)

State Street Equity 500 Index Fund

Class A (SSSVX) Class I (SSSWX) Class K (SSSYX)

State Street Global All Cap Equity ex-U.S. Index Fund

Class A (SSGHX) Class I (SSGJX) Class K (SSGLX)

State Street Small/Mid Cap Equity Index Fund

Class A (SSMJX) Class I (SSMLX) Class K (SSMKX)

The U.S. Securities and Exchange Commission and the U.S. Commodity Futures Trading Commission have not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Class A, Class I and Class K Shares of the Funds.

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Fund Summaries	1
State Street Aggregate Bond Index Fund	1
State Street Equity 500 Index Fund	9
State Street Global All Cap Equity ex-U.S. Index Fund	16
State Street Small/Mid Cap Equity Index Fund	26
Additional Information About Investment Objectives, Principal Strategies and Risks	34
Additional Information About Non-Principal Investment Strategies and Risks	52
Portfolio Holdings Disclosure	54
Management and Organization	55
Shareholder Information	59
Dividends, Distributions and Tax Considerations	72
Financial Intermediary Arrangements	75
Financial Highlights	77
Index/Trademark Licenses/Disclaimers	90

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State Street Aggregate Bond Index Fund

Investment Objective

The State Street Aggregate Bond Index Fund (the “Aggregate Bond Index Fund” or the “Fund”) seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the U.S. dollar denominated investment grade bond market over the long term.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $100,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 62 of the Fund's Prospectus. The expenses shown in the table and the Example reflect the expenses of both the Fund and the Fund's proportionate share of the expenses of State Street Aggregate Bond Index Portfolio (the “Aggregate Bond Index Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	3.75%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee²	0.025%	0.025%	0.025%
Distribution and/or Shareholder Service (12b-1) Fees	0.250%	0.000%	0.000%
Other Expenses³	0.332%	0.332%	0.132%
Total Annual Fund Operating Expenses	0.607%	0.357%	0.157%
Less Fee Waivers and/or Expense Reimbursements^4,5	(0.132%)	(0.132%)	(0.132%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.475%	0.225%	0.025%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.
²	Management Fees have been restated to reflect current fees.

Other Expenses have been restated to reflect current fees.

⁴

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.025% of the Fund's or the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

⁵

SSGA FM is contractually obligated to waive up to the portion of the management fee and/or expenses attributable to acquired fund fees and expenses in connection with the Portfolio's investments in To Be Announced (“TBA”) securities. This fee waiver and/or expense reimbursement may only be terminated with approval of the Fund/Portfolio's Board of Trustees.

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Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell or hold all of your Fund Shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The calculation of costs for the one-year period takes into account the effect of any current contractual fee waivers and/or reimbursements; and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 year	3 years	5 years	10 years
Class A	$422	$549	$688	$1,093
Class I	$23	$101	$187	$439
Class K	$3	$37	$75	$187

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). As a shareholder of the Aggregate Bond Index Portfolio, the Fund bears its ratable share of the transaction costs associated with the portfolio turnover of the Portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 29% of the average value of its portfolio.

Principal Investment Strategies

The Fund is an “index” fund that seeks to track, before fees and expenses, the total return performance of the Bloomberg U.S. Aggregate Bond Index (the “U.S. Aggregate Bond Index” or sometimes referred to in context as the “Index”) over the long term. As an “index” fund, the Fund is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment.

In seeking to track the performance of the Index, the Fund employs a sampling strategy, which means that the Fund will not typically purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index, or securities the Adviser considers to be comparable to securities in the Index, in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Fund will be based on a number of factors, including asset size of the Fund. SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, generally expects the Fund to hold fewer than the total number of securities in the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Fund's investment objective.

Under normal circumstances, the Fund generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in securities that the Adviser determines have economic characteristics that are comparable to the economic characteristics of securities that comprise the Index. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. The Fund may also invest in other debt securities, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Fund may at times purchase or sell futures contracts on fixed-income securities, or options on those futures, in lieu of investing directly in fixed-income securities themselves. The Fund may also purchase or sell futures contracts and related options on the Index (or other fixed-income securities indices). The Fund might do so, for example, in order to adjust the interest-rate sensitivity of the Fund to bring the characteristics of the Fund more closely in line with those of the Index. It might also do so to increase its investment exposure pending investment of cash in bonds or other investments or to reduce its investment exposure in situations where it intends to sell a portion of the securities in its portfolio but the sale has not yet been completed. The Fund may also enter into other derivatives transactions, including the use

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of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Fund may, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

The Index is designed to measure the performance of the U.S. dollar denominated investment grade bond market, which includes investment grade (must be Baa3/BBB-/BBB- or higher using the middle rating of Moody's Investors Service, Inc., Standard & Poor's, and Fitch Inc.) government bonds, investment grade corporate bonds, mortgage pass-through securities, commercial mortgage backed securities and other asset backed securities that are publicly for sale in the United States. The securities in the Index must have at least 1 year remaining to maturity and must have $300 million or more of outstanding face value. Asset backed securities must have a minimum deal size of $500 million and a minimum tranche size of $25 million. For commercial mortgage backed securities, the original aggregate transaction must have a minimum deal size of $500 million, and a minimum tranche size of $25 million; the aggregate outstanding transaction sizes must be at least $300 million to remain in the Index. In addition, the securities must be U.S. dollar denominated, fixed rate, non-convertible, and taxable. Certain types of securities, such as flower bonds, targeted investor notes, and state and local government series bonds are excluded from the Index. Also excluded from the Index are structured notes with embedded swaps or other special features, private placements, floating rate securities and Eurobonds. The Index is market capitalization weighted and the securities in the Index are updated on the last business day of each month. It is not possible to invest directly in the Index.

The Fund expects typically to invest a significant portion of its assets in U.S. agency mortgage pass-through securities up to a total weight that is comparable to that of the Index. Most transactions in mortgage pass-through securities occur through standardized contracts for future delivery in which the exact mortgage pools to be delivered are not specified until a few days prior to settlement, referred to as a “to-be-announced transaction” or “TBA Transaction.” In a TBA Transaction, the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to the settlement date; however, it is not anticipated that the Fund will receive pools, but instead will participate in rolling TBA Transactions. The Fund expects to enter into such contracts on a regular basis.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Aggregate Bond Index Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

The Index is sponsored by Bloomberg Index Services Limited (the “Index Provider”) which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect

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global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

Debt Securities Risk: The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Mortgage-Related and Other Asset-Backed Securities Risk: Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed-income investments. The liquidity of mortgage-related and asset-backed securities may change over time. During periods of falling interest rates, mortgage- and asset-backed securities may be called or prepaid, which may result in the Fund having to reinvest proceeds in other investments at a lower interest rate. During periods of rising interest rates, the average life of mortgage- and asset-backed securities may extend, which may lock in a below-market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. Enforcing rights against the underlying assets or collateral may be difficult, and the underlying assets or collateral may be insufficient if the issuer defaults.

U.S. Government Securities Risk: Certain U.S. government securities are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury, are not supported by the full faith and credit of the U.S. government, and involve increased credit risks.

Indexing Strategy/Index Tracking Risk: The Fund is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. As a result, the Fund's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index and, consequently, the performance, volatility, and risk of the Fund. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Fund's return may not match the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Fund may not be fully invested at times, generally as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to replicate the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Fund's return and that of the Index.

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the Fund holds collateral posted by its counterparty, it may be delayed or prevented from realizing on the collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Derivatives Risk: Derivative transactions can create investment leverage and may have significant volatility. It is possible that a derivative transaction will result in a much greater loss than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Fund's margin, or otherwise honor its obligations. A derivatives transaction may not behave in the manner anticipated by the Adviser or may not have the effect on the Fund anticipated by the Adviser.

Income Risk: The Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by the Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by the Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates.

Large Shareholder Risk: To the extent a large proportion of the shares of the Portfolio are held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program.

Liquidity Risk: Lack of a ready market, stressed market conditions, or restrictions on resale may limit the ability of the Fund to sell a security at an advantageous time or price or at all. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. Illiquidity of the Fund's holdings may also limit the ability of the Fund to obtain cash to meet redemptions on a timely basis. In addition, the Fund, due to limitations on investments in any illiquid securities and/or the difficulty in purchasing and selling such investments, may be unable to achieve its desired level of exposure to a certain market or sector.

Master/Feeder Structure Risk: The Fund pursues its objective by investing substantially all of its assets in another pooled investment vehicle (a “master fund”). The ability of the Fund to meet its investment objective is directly related to the ability of the master fund to meet its investment objective. The Adviser serves as investment adviser to the master fund, leading to potential conflicts of interest. The Fund will bear its pro rata portion of the expenses incurred by the master fund. Substantial redemptions by other investors in a master fund may affect the master fund's investment program adversely and limit the ability of the master fund to achieve its objective.

Risk of Investment in Other Pools: If the Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected and is exposed indirectly to all of the risks applicable to an investment in such other pool. The investment policies of the other pool may not be the same as those of the Fund; as a result, an investment in the other pool may be subject to additional or different risks than those to which the Fund is typically subject. The Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so.

Unconstrained Sector Risk: The Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. Greater investment focus on one or more sectors or industries increases the potential for volatility and the risk that events negatively affecting such sectors or industries could reduce returns, potentially causing the value of the Fund's Shares to decrease, perhaps significantly.

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is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's net asset value. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 3.06% (Q1, 2020)
Lowest Quarterly Return: -3.62% (Q1, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

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	One Year	Five Years	Since Inception	Inception Date
Class A				9/19/2014
Return Before Taxes	-5.88%	2.30%	2.14%
Return After Taxes on Distributions	-6.73%	1.34%	1.10%
Return After Taxes on Distributions and Sale of Fund Shares	-3.26%	1.39%	1.20%
Class I Returns Before Taxes	-1.97%	3.36%	2.97%	9/19/2014
Class K Returns Before Taxes	-1.77%	3.47%	3.04%	9/19/2014
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)	-1.54%	3.57%	3.17%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio and the Fund are Marc DiCosimo and Joanna Madden. They have served as portfolio managers of the Fund and the Portfolio since 2014 and 2016, respectively.

Marc DiCosimo, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Fixed Income Beta Solutions Group. He joined the Adviser in 2013.

Joanna Madden is a Vice President of the Adviser and a Portfolio Manager in the Fixed Income Beta Solutions Group. She joined the Adviser in 2003.

Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

If you wish to purchase or redeem Fund Shares through a broker, bank or other financial intermediary (“Financial Intermediary”), please contact that Financial Intermediary directly. Your Financial Intermediary may have different or additional requirements for opening an account and/or for the processing of purchase and redemption orders, or may be closed at times when the Fund is open. Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

The Fund's distributions are expected to be taxed as ordinary income and/or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or IRA. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Fund Shares through a broker-dealer or other Financial Intermediary (such as a bank), the Adviser or its affiliates may pay the Financial Intermediary for certain activities related to the Fund, including educational training programs, conferences, the development of technology platforms and reporting systems, or other services related to the sale or promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your Financial Intermediary's website for more information.

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State Street Equity 500 Index Fund

Investment Objective

The investment objective of the State Street Equity 500 Index Fund (the “Equity 500 Index Fund” or sometimes referred to in context as the “Fund”) is to replicate as closely as possible, before expenses, the performance of the Standard & Poor's 500 Index (the “S&P 500” or sometimes referred to in context as the “Index”).

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 62 of the Fund's Prospectus. The expenses shown in the table and the Example reflect the expenses of both the Fund and the Fund's proportionate share of the expenses of State Street Equity 500 Index II Portfolio (the “Equity 500 Index II Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee	0.02%	0.02%	0.02%
Distribution and/or Shareholder Service (12b-1) Fees	0.25%	0.00%	0.00%
Other Expenses²	0.30%	0.30%	0.10%
Total Annual Fund Operating Expenses	0.57%	0.32%	0.12%
Less Fee Waivers and/or Expense Reimbursements³	(0.10%)	(0.10%)	(0.10%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.47%	0.22%	0.02%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

Other Expenses have been restated to reflect current fees.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.02% of the Fund's or the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

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Example:

	1 year	3 years	5 years	10 years
Class A	$571	$689	$817	$1,192
Class I	$23	$93	$170	$396
Class K	$2	$28	$58	$144

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). As a shareholder of the Equity 500 Index II Portfolio, the Fund bears its ratable share of the transaction costs associated with the portfolio turnover of the Portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 6% of the average value of its portfolio.

Principal Investment Strategies

The Fund uses a passive management strategy designed to track the performance of the S&P 500. The Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the U.S. equities market. As of February 28, 2022, a significant portion of the Index comprised companies in the Information Technology, Health Care and Consumer Discretionary sectors, although this may change from time to time.

The Fund is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. Instead, the Fund, using a “passive” or “indexing” investment approach, seeks to provide investment results that, before expenses, correspond generally to the total return of the S&P 500.

The Fund generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Fund will not invest less than 80% of its total assets in stocks in the Index. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. For this purpose, “total assets” means net assets plus borrowings, if any. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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not yet been completed. The Fund may also enter into other derivatives transactions, including the use of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Fund may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Equity 500 Index II Portfolio, which has substantially similar investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio, and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

Principal Risks

Equity Investing Risk: The market prices of equity securities owned by the Fund may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer and also may decline due to general industry or market conditions that are not specifically related to a particular company. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

Information Technology Sector Risk: Market or economic factors impacting information technology companies could have a major effect on the value of the Fund's investments. The value of stocks of information technology companies is particularly vulnerable to rapid changes in technology product cycles, rapid product obsolescence, government regulation and competition, both domestically and internationally, including competition from foreign competitors with lower production costs. Like other technology companies, information technology companies may have limited product lines, markets, financial resources or personnel. Stocks of technology companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Information technology companies are heavily dependent on patent and intellectual property rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

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While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Fund's return may not match the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Fund may not be fully invested at times, generally as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to replicate the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Fund's return and that of the Index.

Consumer Discretionary Sector Risk: The success of consumer product manufacturers and retailers is tied closely to the performance of the overall global economy, interest rates, competition and consumer confidence. Success depends heavily on disposable household income and consumer spending. Also, companies in the consumer discretionary sector may be subject to severe competition, which may have an adverse impact on their respective profitability. Changes in demographics and consumer tastes can also affect the demand for, and success of, consumer products and services in the marketplace.

Counterparty Risk: The Fund will be subject to credit risk with respect to the counterparties with which the Fund enters into derivatives contracts, repurchase agreements, reverse repurchase agreements, and other transactions. If a counterparty fails to meet its contractual obligations, the Fund may be unable to terminate or realize any gain on the investment or transaction, or to recover collateral posted to the counterparty, resulting in a loss to the Fund. If the Fund holds collateral posted by its counterparty, it may be delayed or prevented from realizing on the collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Health Care Sector Risk: Companies in the health care sector are subject to extensive government regulation and their profitability can be significantly affected by restrictions on government reimbursement for medical expenses, rising costs of medical products and services, pricing pressure (including price discounting), limited product lines and an increased emphasis on the delivery of healthcare through outpatient services. Companies in the health care sector are heavily dependent on obtaining and defending patents, which may be time consuming and costly, and the expiration of patents may also adversely affect the profitability of these companies. Health care companies are also subject to extensive litigation based on product liability and similar claims. In addition, their products can become obsolete due to industry innovation, changes in technologies or other market developments. Many new products in the health care sector require significant research and development and may be subject to regulatory approvals, all of which may be time consuming and costly with no guarantee that any product will come to market.

Large-Capitalization Securities Risk: Returns on investments in securities of large companies could trail the returns on investments in securities of smaller and mid-sized companies. Larger companies may be unable to respond as quickly as smaller and mid-sized companies to competitive challenges or to changes in business, product, financial, or other market conditions. Larger companies may not be able to maintain growth at the high rates that may be achieved by well-managed smaller and mid-sized companies.

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Fund, due to limitations on investments in any illiquid securities and/or the difficulty in purchasing and selling such investments, may be unable to achieve its desired level of exposure to a certain market or sector.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Class A shares' returns have varied for each full calendar year shown. The effect of sales charges, applicable to Class A shares only, is not reflected in the bar chart; if these amounts were reflected, returns would be lower. For periods prior to September 17, 2014, the inception date for Class A shares, the performance information shown is that of the Administrative Shares of the Fund, adjusted to reflect the higher class-related operating fees and expenses of Class A shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 20.40% (Q2, 2020)
Lowest Quarterly Return: -19.68% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

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Shares of the Fund. After tax returns are shown only for Class A and after tax returns will vary for other share classes. Except for differences in returns resulting from differences in fees, expenses, and sales charges (as applicable), all share classes would have substantially similar returns because all share classes invest in the same portfolio of securities.

	One Year	Five Years	Ten Years	Inception Date
Class A				9/17/2014
Return Before Taxes	21.22%	16.60%	15.32%
Return After Taxes on Distributions	20.54%	15.53%	14.59%
Return After Taxes on Distributions and Sale of Fund Shares	12.99%	13.06%	12.72%
Class I Returns Before Taxes	28.25%	18.16%	16.24%	9/17/2014
Class K Returns Before Taxes	28.51%	18.35%	16.39%	9/17/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	16.55%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio and the Fund are Michael Feehily, Karl Schneider and Amy Scofield. Michael Feehily has served on the Fund and the Portfolio/the prior master portfolio in which the Fund has invested since 2014. Karl Schneider has served on the Fund and the Portfolio/the prior master portfolio in which the Fund has invested since 2002. Amy Scofield has served on the Fund and the Portfolio/the prior master portfolio in which the Fund has invested since 2012.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

Amy Scofield is a Principal of the Adviser and a Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2010.

Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

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Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

The Fund's distributions are expected to be taxed as ordinary income, qualified dividend income and/or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or IRA. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Global All Cap Equity ex-U.S. Index Fund

Investment Objective

The State Street Global All Cap Equity ex-U.S. Index Fund (the “Global All Cap Equity ex-U.S. Index Fund” or the “Fund”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of a broad-based index of world (ex-U.S.) equity markets over the long term.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 62 of the Fund's Prospectus. The expenses shown in the table and the Example reflect the expenses of both the Fund and the Fund's proportionate share of the expenses of State Street Global All Cap Equity ex-U.S. Index Portfolio (the “Global All Cap Equity ex-U.S. Index Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee	0.060%	0.060%	0.060%
Distribution and/or Shareholder Service (12b-1) Fees	0.250%	0.000%	0.000%
Other Expenses²	0.370%	0.370%	0.170%
Total Annual Fund Operating Expenses	0.680%	0.430%	0.230%
Less Fee Waivers and/or Expense Reimbursements³	(0.165%)	(0.165%)	(0.165%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.515%	0.265%	0.065%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

Other Expenses have been restated to reflect current fees.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund/Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, with respect to the Fund, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees, and, with respect to the Portfolio, distribution, shareholder servicing and sub-transfer agency fees) exceed 0.015% of the Fund's and 0.08% of the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund's/Portfolio's Board of Trustees.

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Example:

	1 year	3 years	5 years	10 years
Class A	$575	$715	$868	$1,312
Class I	$27	$121	$224	$526
Class K	$7	$57	$113	$277

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). As a shareholder of the Global All Cap Equity ex-U.S. Index Portfolio, the Fund bears its ratable share of the transaction costs associated with the portfolio turnover of the Portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 2% of the average value of its portfolio.

Principal Investment Strategies

The Fund is an “index” fund that seeks to track, before fees and expenses, the total return performance of the MSCI ACWI ex USA Investable Market Index (the “MSCI ACWI ex USA IMI Index” or sometimes referred to in context as the “Index”) over the long term. As an “index” fund, the Fund is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. As of February 28, 2022, a significant portion of the Index comprised companies in the financial sector, although this may change from time to time. As of February 28, 2022, a significant portion of the Index comprised companies located in Japan and the United Kingdom and a significant portion of the Index constituents are denominated in the Euro, Yen and the Pound Sterling although this may change from time to time.

Under normal circumstances, the Fund generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) providing exposure to securities comprising the Index. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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been completed. The Fund may also enter into other derivatives transactions, including the use of options, forwards or swap transactions, in lieu of investing directly in the stocks making up the Index. The Fund may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

The Index is a free float-adjusted market capitalization index that is designed to measure the combined equity market performance of securities, across all market capitalizations, in developed and emerging market countries excluding the United States. All listed equity securities and listed securities that exhibit characteristics of equity securities, except mutual funds, ETFs, equity derivatives, limited partnerships and most investment trusts, are eligible for inclusion. Countries covered in the Index have historically included, among others, Australia, Austria, Belgium, Brazil, Canada, Chile, China, Colombia, Czech Republic, Denmark, Egypt, Finland, France, Germany, Greece, Hong Kong, Hungary, India, Indonesia, Ireland, Israel, Italy, Japan, Korea, Kuwait, Malaysia, Mexico, the Netherlands, New Zealand, Norway, Peru, Philippines, Poland, Portugal, Qatar, Russia, Saudi Arabia, Singapore, South Africa, Spain, Sweden, Switzerland, Taiwan, Thailand, Turkey, United Arab Emirates and the United Kingdom. It is not possible to invest directly in the Index.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Global All Cap Equity ex-U.S. Index Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

The Index is sponsored by MSCI Inc. (the “Index Provider”), which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks

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be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent that the Fund buys securities denominated in a foreign currency, there are special risks such as changes in currency exchange rates and the risk that a foreign government could regulate foreign exchange transactions. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

Geographic Focus Risk: The performance of a fund that is less diversified across countries or geographic regions will be closely tied to market, currency, economic, political, environmental, or regulatory conditions and developments in the countries or regions in which the fund invests, and may be more volatile than the performance of a more geographically-diversified fund.

Europe: Developed and emerging market countries in Europe will be significantly affected by the fiscal and monetary controls of the Economic and Monetary Union of the European Union (“EU”). Changes in regulations on trade, decreasing imports or exports, changes in the exchange rate of the euro and recessions among European countries may have a significant adverse effect on the economies of other European countries. In addition, one or more countries may abandon the euro and/or withdraw from the EU For example, on January 31, 2020, the United Kingdom formally withdrew from the EU (commonly referred to as “Brexit”) and, after a transition period, left the EU single market and customs union under the terms of a new trade agreement on December 31, 2020. The agreement governs the new relationship between the United Kingdom and EU with respect to trading goods and services, but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. The full scope and nature of the consequences of the exit are not at this time known and are unlikely to be known for a significant period of time. It is also unknown whether the United Kingdom's exit will increase the likelihood of other countries also departing the EU Any exits from the EU, or the possibility of such exits, may have a significant impact on the United Kingdom, Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for such economies that could potentially have an adverse effect on the value of the Fund's investments. In addition, a number of countries in Europe have suffered terrorist attacks and additional attacks may occur in the future. Such attacks may cause uncertainty in financial markets and may adversely affect the performance of the issuers to which the Fund has exposure.

Japan: The growth of Japan's economy has historically lagged that of its Asian neighbors and other major developed economies. The Japanese economy is heavily dependent on international trade and has been adversely affected by trade tariffs, other protectionist measures, competition from emerging economies and the economic conditions of its trading partners. China has become an important trading partner with Japan, yet the countries' political relationship has become strained. Should political tension increase, it could adversely affect the economy, especially the export sector, and destabilize the region as a whole. Japan also remains heavily dependent on oil imports, and higher commodity prices could therefore have a negative impact on the economy. The Japanese yen has fluctuated widely at times and any increase in its value may cause a decline in exports that could weaken the Japanese economy. Japan has, in the past, intervened in the currency markets to attempt to maintain or reduce the value of the yen. Japanese intervention in the currency markets could cause the value of the yen to fluctuate sharply and unpredictably and could cause losses to investors. Japan has an aging workforce and has experienced a significant population decline in recent years. Japan's labor market appears to be undergoing fundamental structural changes, as a labor market traditionally accustomed to lifetime employment adjusts to meet the need for increased labor mobility, which may adversely affect Japan's economic competitiveness. Natural disasters, such as earthquakes, volcanoes, typhoons or tsunamis, could occur in Japan or surrounding areas and could negatively affect the Japanese economy and, in turn, the Fund.

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of financial services to the United States and other European countries and, therefore, a prolonged slowdown in the financial services sector may have a negative impact on the British economy. Continued governmental involvement or control in certain sectors may stifle competition in certain sectors or cause adverse effects on economic growth.

Currency Risk: The value of the Fund's assets may be affected favorably or unfavorably by currency exchange rates, currency exchange control regulations, and delays, restrictions or prohibitions on the repatriation of foreign currencies. Foreign currency exchange rates may have significant volatility, and changes in the values of foreign currencies against the U.S. dollar may result in substantial declines in the values of the Fund's assets denominated in foreign currencies.

Depositary Receipts Risk: Investments in depositary receipts may be less liquid and more volatile than the underlying securities in their primary trading market. If a depositary receipt is denominated in a different currency than its underlying securities, the Fund will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based. To the extent the Fund invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

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cantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. These risks are generally greater for investments in frontier market countries, which typically have smaller economies or less developed capital markets than traditional emerging market countries.

Financial Sector Risk: Financial services companies are subject to extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, the interest rates and fees they can charge, the scope of their activities, the prices they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds and can fluctuate significantly when interest rates change or due to increased competition. In addition, deterioration of the credit markets generally may cause an adverse impact in a broad range of markets, including U.S. and international credit and interbank money markets generally, thereby affecting a wide range of financial institutions and markets. Certain events in the financial sector may cause an unusually high degree of volatility in the financial markets, both domestic and foreign, and cause certain financial services companies to incur large losses. Securities of financial services companies may experience a dramatic decline in value when such companies experience substantial declines in the valuations of their assets, take action to raise capital (such as the issuance of debt or equity securities), or cease operations. Credit losses resulting from financial difficulties of borrowers and financial losses associated with investment activities can negatively impact the sector. Insurance companies may be subject to severe price competition. Adverse economic, business or political developments could adversely affect financial institutions engaged in mortgage finance or other lending or investing activities directly or indirectly connected to the value of real estate.

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Small-, Mid-, and Micro-Capitalization Securities Risk: The securities of small-, mid- and micro-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of smaller companies may trade less frequently and in smaller volumes than more widely held securities. Some securities of smaller issuers may be illiquid or may be restricted as to resale, and their values may have significant volatility. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. Returns on investments in securities of small-, mid- and micro-capitalization companies could trail the returns on investments in securities of larger companies.

Valuation Risk: Some portfolio holdings, potentially a large portion of the Fund's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. In addition, there is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

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Performance

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 18.22% (Q2, 2020)
Lowest Quarterly Return: -24.87% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. After-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). Effective October 9, 2019 (the “Benchmark Index Change Date”), the Fund's benchmark index changed from the MSCI ACWI ex USA Index (the “Previous Benchmark Index”) to the MSCI ACWI ex USA Investable Market Index, consistent with a change in the Fund's principal investment strategy to track the performance of the current index. Performance of the Fund prior to the Benchmark Index Change Date is therefore based on the Fund's investment strategy to track the Previous Benchmark Index. After tax returns are shown only for Class A and after tax returns will vary for other share classes. Except for differences in returns resulting from differences in fees, expenses, and sales charges (as applicable), all share classes would have substantially similar returns because all share classes invest in the same portfolio of securities.

	One Year	Five Years	Since Inception	Inception Date
Class A				9/17/2014
Return Before Taxes	2.21%	8.19%	4.12%
Return After Taxes on Distributions	1.38%	7.17%	3.35%
Return After Taxes on Distributions and Sale of Fund Shares	1.98%	6.32%	3.12%
Class I Returns Before Taxes	8.21%	9.66%	5.17%	9/17/2014
Class K Returns Before Taxes	8.36%	9.83%	5.29%	9/17/2014
MSCI ACWI ex USA Investable Market Index/MSCI ACWI ex USA Index¹ (reflects no deduction for fees, expenses or taxes other than withholding taxes on reinvested dividends)	8.53%	9.88%	5.40%

¹	Returns shown are reflective of the Index for periods beginning on the Benchmark Index Change Date and the Previous Benchmark Index for periods prior to the Benchmark Index Change Date.

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio and the Fund are Michael Feehily, Karl Schneider and Olga Winner. They have served on the Fund and the Portfolio since inception in 2014.

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Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

Olga Winner, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2007.

Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

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Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Small/Mid Cap Equity Index Fund

Investment Objective

The State Street Small/Mid Cap Equity Index Fund (the “Small/Mid Cap Equity Index Fund” or the “Fund”) seeks to provide investment results that, before expenses, correspond generally to the total return of an index that tracks the performance of mid-to small- capitalization exchange traded U.S. equity securities.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 62 of the Fund's Prospectus. The expenses shown in the table and the Example reflect the expenses of both the Fund and the Fund's proportionate share of the expenses of State Street Small/Mid Cap Equity Index Portfolio (the “Small/Mid Cap Equity Index Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee	0.030%	0.030%	0.030%
Distribution and/or Shareholder Service (12b-1) Fees	0.250%	0.000%	0.000%
Other Expenses²	0.340%	0.340%	0.140%
Total Annual Fund Operating Expenses	0.620%	0.370%	0.170%
Less Fee Waivers and/or Expense Reimbursements³	(0.125%)	(0.125%)	(0.125%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.495%	0.245%	0.045%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

Other Expenses have been restated to reflect current fees.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees and, with respect to the Portfolio, acquired fund fees) exceed 0.045% of the Fund's and 0.03% of the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

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Example:

	1 year	3 years	5 years	10 years
Class A	$573	$701	$841	$1,247
Class I	$25	$106	$195	$456
Class K	$5	$42	$83	$205

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). As a shareholder of the Small/Mid Cap Equity Index Portfolio, the Fund bears its ratable share of the transaction costs associated with the portfolio turnover of the Portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 28% of the average value of its portfolio.

Principal Investment Strategies

The Fund uses a passive management strategy designed to track the performance of the Russell Small Cap Completeness Index (the “Index”). The Index is a float-adjusted, market capitalization index which measures the performance of the Russell 3000^® Index companies excluding S&P 500^® constituents. The Index is constructed to provide a comprehensive and unbiased barometer of the extended broad market beyond the S&P 500 exposure. The index is completely reconstituted annually to ensure new and growing equities are included. As of February 28, 2022, the market capitalization of the companies included in the Index ranged from $5.74 million to 86.68 billion. As of February 28, 2022, the Index comprised 2,545 securities. As of February 28, 2022, a significant portion of the Index comprised companies in the information technology, financials, industrials and consumer discretionary sectors, although this may change from time to time.

The Fund generally intends to invest in all stocks comprising the Index in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Portfolio invests at least 80% of its net assets (plus borrowings, if any) in stocks in the Index. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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The Fund may purchase or sell futures contracts on the Index, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Fund might do so, for example, in order to increase its investment exposure pending investment of cash in the stocks comprising the Index. Alternatively, the Fund might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Fund may also enter into other derivatives transactions, including the use of options or swap transactions relating to the Index or any securities comprising the Index, in lieu of investing directly in the stocks making up the Index. The Fund may, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the State Street Small/Mid Cap Equity Index Portfolio, a separate series of the State Street Institutional Investment Trust, with an identical investment objective as the Fund and that has substantially identical investment policies, strategies and risks, to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio and it participates in the investment returns achieved by the Portfolio.

The Index is sponsored by FTSE Russell (the “Index Provider”), which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks

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Industrial Sector Risk: Industrial companies are affected by supply and demand both for their specific product or service and for industrial sector products in general. Government regulation, world events, exchange rates and economic conditions, technological developments and liabilities for environmental damage and general civil liabilities will likewise affect the performance of these companies. Aerospace and defense companies, a component of the industrial sector, can be significantly affected by government spending policies because companies involved in this industry rely, to a significant extent, on U.S. and foreign government demand for their products and services. Thus, the financial condition of, and investor interest in, aerospace and defense companies are heavily influenced by governmental defense spending policies which are typically under pressure from efforts to control the U.S. (and other) government budgets. Transportation securities, a component of the industrial sector, are cyclical and have occasional sharp price movements which may result from changes in the economy, fuel prices, labor agreements and insurance costs.

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cretionary sector may be subject to severe competition, which may have an adverse impact on their respective profitability. Changes in demographics and consumer tastes can also affect the demand for, and success of, consumer products and services in the marketplace.

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would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. In addition, there is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

Performance

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 30.41% (Q2, 2020)
Lowest Quarterly Return: -28.02% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class A				10/15/2015
Return Before Taxes	6.07%	13.74%	13.21%
Return After Taxes on Distributions	3.60%	11.95%	11.68%
Return After Taxes on Distributions and Sale of Fund Shares	4.77%	10.25%	10.04%
Class I Returns Before Taxes	12.22%	15.27%	14.50%	10/15/2015
Class K Returns Before Taxes	12.45%	15.40%	13.34%	8/11/2015
Russell Small Cap Completeness Index (reflects no deduction for fees, expenses or taxes)	12.64%	15.53%	13.49%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio and the Fund are Michael Feehily, Karl Schneider and Ted Janowsky each of which has served as a portfolio manager of the Fund and the Portfolio since inception in 2015.

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Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

Ted Janowsky, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. He joined the Adviser in 2005.

Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Table of Contents

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The State Street Institutional Investment Trust's (the “Trust”) Board of Trustees (the “Board”) may change each Fund's investment strategies and other policies without shareholder approval, except as otherwise indicated. The Board may change each Fund's investment objective without shareholder approval. If the Trustees were to approve a change to the Equity 500 Index Fund's investment objective, shareholders would receive advance notice.

State Street Aggregate Bond Index Fund

Principal Investment Strategies

In seeking to track the performance of the Index, the Fund employs a sampling strategy, which means that the Fund will not typically purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index, or securities the Adviser considers to be comparable to securities in the Index, in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Fund will be based on a number of factors, including asset size of the Fund. SSGA FM generally expects the Fund to hold fewer than the total number of securities in the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Fund's investment objective.

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state and local government series bonds are excluded from the Index. Also excluded from the Index are structured notes with embedded swaps or other special features, private placements, floating rate securities and Eurobonds. The Index is market capitalization weighted and the securities in the Index are updated on the last business day of each month. It is not possible to invest directly in the Index.

Index Futures Contracts and Related Options. The Fund may buy and sell futures contracts and options on those futures contracts. An “index futures” contract is a contract to buy or sell units of an index at an agreed price on a specified future date. Depending on the change in value of the Index between the time when the Fund enters into and closes out an index future or option transaction, the Fund realizes a gain or loss. Options and futures transactions involve risks. For example, it is possible that changes in the prices of futures contracts will not correlate precisely with changes in the value of the Index. In those cases, use of futures contracts and related options might decrease the correlation between the return of the Fund and the return of the Index. In addition, the Fund incurs transaction costs in entering into, and closing out, positions in futures contracts and related options. Funds that enter into contracts with counterparties run the risk that the counterparty will be unwilling or unable to make timely settlement payments or otherwise honor its obligations. This risk is typically less for exchange-traded derivatives, such as those the Fund may invest in.

These costs typically have the effect of reducing the correlation between the return of the Fund and the return of the Index. Because the market for futures contracts and options may be illiquid, the Fund may have to hold a contract or option when the Adviser would otherwise have closed out the position, or it may only be able to close out at a price lower than what the Adviser believes is the fair value of the contract or option, thereby potentially reducing the return of the Fund.

Other Derivative Transactions. The Fund may enter into derivatives transactions involving options and swaps. These transactions involve many of the same risks as those described above under “Index Futures Contracts and Related Options.” In addition, since many of such transactions are conducted directly with counterparties, and not on an exchange or board of trade, the Fund's ability to realize any investment return on such transactions may depend on the counterparty's ability or willingness to meet its obligations.

Additional Index Information. The components of the Index are reconstituted and rebalanced monthly.

State Street Equity 500 Index Fund

Principal Investment Strategies

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The Fund generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Fund will not invest less than 80% of its total assets in stocks in the Index. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. For this purpose, “total assets” means net assets plus borrowings, if any. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Fund may at times purchase or sell futures contracts, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Fund might do so, for example, in order to increase its investment exposure pending investment of cash in the stocks comprising the Index. Alternatively, the Fund might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Fund may also enter into other derivatives transactions, including the use of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Fund may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

The S&P 500 measures the performance of the large-cap segment of the market, is comprised of the stocks of 500 industry-leading companies and is considered to be a proxy of the U.S. equity stock market in general. The S&P 500 is unmanaged and does not reflect the actual cost of investing in the instruments that compose the Index. Additionally, the returns of the S&P 500 do not reflect the effect of fees, expenses and taxes. Index constituents are added and removed on an as-needed basis. The Index is rebalanced quarterly.

Stocks in the S&P 500 are weighted according to their float adjusted market capitalizations (i.e., the number of float shares outstanding multiplied by the stock's current price). The companies selected for inclusion in the S&P 500 are those of large publicly held companies which generally have large market values within their respective industries. The composition of the S&P 500 is determined by S&P Dow Jones Indices and is based on such factors as the domicile, exchange listing, organizational structure and share type, market capitalization, liquidity, financial viability, tracking stocks, multiple share classes and investable weight factor of each stock and its adequacy as a representation of stocks in a particular industry group, and may be changed from time to time. The S&P 500 is a product of S&P Dow Jones Indices LLC or its affiliates (“SPDJI”) and has been licensed for use by the Adviser. S&P^®, Standard & Poor's^®, and S&P 500^® are registered trademarks of Standard & Poor's Financial Services LLC (“S&P”) and these trademarks have been licensed for use by SPDJI and sub-licensed for certain purposes by the Adviser.

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the return of the Fund and the return of the Index. In addition, the Fund incurs transaction costs in entering into, and closing out, positions in futures contracts and related options. Funds that enter into contracts with counterparties run the risk that the counterparty will be unwilling or unable to make timely settlement payments or otherwise honor its obligations. This risk is typically less for exchange-traded derivatives, such as those the Fund may invest in.

State Street Global All Cap Equity ex-U.S. Index Fund

Principal Investment Strategies

The Fund may also purchase or sell futures contracts, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Fund might do so, for example, in order to increase its investment exposure pending investment of cash in stocks or other investments. Alternatively, the Fund might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Fund may also enter into other derivatives transactions, including the use of options, forwards or swap transactions, in lieu of investing directly in the stocks making up the Index. The Fund may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

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mutual funds, ETFs, equity derivatives, limited partnerships and most investment trusts, are eligible for inclusion. Countries covered in the Index have historically included, among others, Australia, Austria, Belgium, Brazil, Canada, Chile, China, Colombia, Czech Republic, Denmark, Egypt, Finland, France, Germany, Greece, Hong Kong, Hungary, India, Indonesia, Ireland, Israel, Italy, Japan, Korea, Kuwait, Malaysia, Mexico, the Netherlands, New Zealand, Norway, Peru, Philippines, Poland, Portugal, Qatar, Russia, Saudi Arabia, Singapore, South Africa, Spain, Sweden, Switzerland, Taiwan, Thailand, Turkey, United Arab Emirates and the United Kingdom. It is not possible to invest directly in the Index.

Additional Index Information. The Index's components are reconstituted on an ongoing, event-driven basis and are rebalanced quarterly. The Index Provider classifies each issuer in one country. The Index Provider generally determines the country classification of an issuer based on the issuer's country of incorporation and the primary listing of its securities. To the extent that an issuer is incorporated in a different country than the country in which its securities are principally traded, the Index Provider considers the following additional set of criteria to determine the issuer's country classification: (i) the secondary listings of the issuer's securities, if any; (ii) the geographic distribution of the issuer's shareholder base; (iii) the location of the issuer's headquarters; (iv) the geographic distribution of the issuer's operations (in terms of assets and revenues); (v) the issuer's history with respect to these criteria; and (vi) the country in which investors consider the issuer to be most appropriately classified based on communications between the Index Provider and investors.

State Street Small/Mid Cap Equity Index Fund

Principal Investment Strategies

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reconstituted annually to ensure new and growing equities are included. As of February 28, 2022, the market capitalization of the companies included in the Index ranged from $5.74 million to 86.68 billion. As of February 28, 2022, the Index comprised 2,545 securities. As of February 28, 2022, a significant portion of the Index comprised companies in the information technology, financials, industrials and consumer discretionary sectors, although this may change from time to time.

The Fund generally intends to invest in all stocks comprising the Index in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Portfolio invests at least 80% of its net assets (plus borrowings, if any) in stocks in the Index. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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Additional Index Information. The Index's components are reconstituted annually and rebalanced monthly.

Additional Information About Risks

The Funds are subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure. Each principal risk without a parenthetical indicating a single Fund's name is applicable to each Fund.

Call/Prepayment Risk (principal risk for the Aggregate Bond Index Fund). Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by a Fund earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by a Fund are prepaid. In any such case, a Fund may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Fund's income.

Consumer Discretionary Sector Risk (principal risk for the Equity 500 Index Fund and Small/Mid Cap Equity Index Fund). The success of consumer product manufacturers and retailers is tied closely to the performance of the overall global economy, interest rates, competition and consumer confidence. Success depends heavily on disposable household income and consumer spending. Also, companies in the consumer discretionary sector may be subject to severe competition, which may have an adverse impact on their respective profitability. Changes in demographics and consumer tastes can also affect the demand for, and success of, consumer products and services in the marketplace.

Counterparty Risk. A Fund will be subject to credit risk with respect to the counterparties with which the Fund enters into derivatives contracts and other transactions such as repurchase agreements or reverse repurchase agreements. A Fund's ability to profit from these types of investments and transactions will depend on the willingness and ability of its counterparty to perform its obligations. If a counterparty fails to meet its contractual obligations, a Fund may be unable to terminate or realize any gain on the investment or transaction, resulting in a loss to the Fund. A Fund may experience significant delays in obtaining any recovery in an insolvency, bankruptcy, or other reorganization proceeding involving its counterparty (including recovery of any collateral posted by it) and may obtain only a limited recovery or may obtain no recovery in such circumstances. If a Fund holds collateral posted by its counterparty, it may be delayed or prevented from realizing on the collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty. Under applicable law or contractual provisions, including if a Fund enters into an investment or transaction with a financial institution and such financial institution (or an affiliate of the financial institution) experiences financial difficulties, then the Fund may in certain situations be prevented or delayed from exercising its rights to terminate the investment or transaction, or to realize on any collateral and may result in the suspension of payment and delivery obligations of the parties under such investment or transactions or in another institution being substituted for that financial institution without the consent of the Fund. Further, a Fund may be subject to “bail-in” risk under applicable law whereby, if required by the financial institution's authority, the financial institution's liabilities could be written down, eliminated or converted into equity or an alternative instrument of ownership. A bail-in of a financial institution may result in a reduction in value of some or all of its securities and, if a Fund holds such securities or has entered into a transaction with such a financial security when a bail-in occurs, such Fund may also be similarly impacted.

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Credit Risk (principal risk for the Aggregate Bond Index Fund). Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by a Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

The credit rating assigned to any particular investment does not necessarily reflect the issuer's current financial condition and does not reflect an assessment of an investment's volatility or liquidity. Securities rated in the lowest category of investment-grade are considered to have speculative characteristics. If a security held by a Fund loses its rating or its rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

Currency Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund). Investments in issuers in different countries are often denominated in currencies other than the U.S. dollar. Changes in the values of those currencies relative to the U.S. dollar may have a positive or negative effect on the values of a Fund's investments denominated in those currencies. The values of other currencies relative to the U.S. dollar may fluctuate in response to, among other factors, interest rate changes, intervention (or failure to intervene) by national governments, central banks, or supranational entities such as the International Monetary Fund, the imposition of currency controls, and other political or regulatory developments. Currency values can decrease significantly both in the short term and over the long term in response to these and other developments. Continuing uncertainty as to the status of the Euro and the Economic and Monetary Union of the European Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU, or any continued uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's portfolio investments.

Debt Securities Risk (principal risk for the Aggregate Bond Index Fund). The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of a Fund's fixed income securities to decrease, an adverse impact on the liquidity of a Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, a Fund's yield can be low, and a Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by a Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Depositary Receipts Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund). American Depositary Receipts (“ADRs”) are typically trust receipts issued by a U.S. bank or trust company that evidence an indirect interest in underlying securities issued by a foreign entity. Global Depositary Receipts (“GDRs”), European Depositary Receipts (“EDRs”), and other types of depositary receipts are typically issued by non-U.S. banks or financial institutions to evidence an interest in underlying securities issued by either a U.S. or a non-U.S. entity. Investments in non-U.S. issuers through ADRs, GDRs, EDRs, and other types of depositary receipts generally involve risks applicable to other types of investments in non-U.S. issuers. Investments in depositary receipts may be less liquid and more volatile than the underlying securities in their primary trading market. If a depositary receipt is denominated in a different currency than its underlying securities, the Portfolio and, therefore, the Fund will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. There may be less publicly available information regarding the issuer of the securities underlying a depositary receipt than if those securities were traded directly in U.S. securities markets. Depositary receipts may or may not be sponsored by the issuers of the underlying securities, and information regarding issuers of

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securities underlying unsponsored depositary receipts may be more limited than for sponsored depositary receipts. The values of depositary receipts may decline for a number of reasons relating to the issuers or sponsors of the depositary receipts, including, but not limited to, insolvency of the issuer or sponsor. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based. To the extent the Fund invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

Derivatives Risk. A derivative is a financial contract the value of which depends on, or is derived from, the value of an underlying asset, interest rate, or index. Derivative transactions typically involve leverage and may have significant volatility. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that a Fund may not be able to close out a derivative transaction at a favorable time or price. Risks associated with derivative instruments include potential changes in value in response to interest rate changes or other market developments or as a result of the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Adviser anticipated or a different or less favorable effect than the Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that a Fund may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that a Fund will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to a Fund due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

Emerging Markets Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund). Investments in emerging markets are generally subject to a greater risk of loss than investments in developed markets. This may be due to, among other things, the possibility of greater market volatility, lower trading volume and liquidity, greater risk of expropriation, nationalization, and social, political and economic instability, greater reliance on a few industries, international trade or revenue from particular commodities, less developed accounting, legal and regulatory systems, higher levels of inflation, deflation or currency devaluation, greater risk of market shut down, and more significant governmental limitations on investment policy as compared to those typically found in a developed market. The Public Company Accounting Oversight Board, which regulates auditors of U.S. public companies, is unable to inspect audit work papers in certain foreign countries. Investors in foreign countries often have limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the U.S. Securities and Exchange Commission, the U.S. Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited. In addition, issuers (including governments) in emerging market countries may have less financial stability than in other countries. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. A Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. There is also the potential for unfavorable action such as embargo and acts of war. As a result, there will tend to be an increased risk of price volatility in investments in emerging market countries, which may be magnified by currency fluctuations relative to the U.S. dollar. Settlement and asset custody practices for transactions in emerging markets may differ from those in developed markets. Such differences may include possible delays in settlement and certain settlement practices, such as delivery of securities prior to receipt of payment, which increase the likelihood of a “failed settlement.” Failed settlements can result in losses. For these and other reasons, investments in emerging markets are often considered speculative.

Equity Investing Risk (principal risk for the Equity 500 Index Fund, Global All Cap Equity ex-U.S. Index Fund and Small/Mid Cap Equity Index Fund). The market prices of equity securities owned by a Fund may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer, such as management performance, financial leverage, non-compliance with regulatory requirements, and reduced demand for the issuer's goods or services. The values of equity securities also may decline due to general industry or market

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conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, or adverse investor sentiment generally. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

Extension Risk (principal risk for the Aggregate Bond Index Fund). During periods of rising interest rates, the average life of certain types of securities may be extended because of slower-than-expected principal payments. This may increase the period of time during which an investment earns a below-market interest rate, increase the security's duration and reduce the value of the security. Extension risk may be heightened during periods of adverse economic conditions generally, as payment rates decline due to higher unemployment levels and other factors.

Financial Sector Risk (principal risk for the Global All Cap Equity ex-U.S. Index and Small/Mid Cap Equity Index Fund). Financial services companies are subject to extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, the interest rates and fees they can charge, the scope of their activities, the prices they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds and can fluctuate significantly when interest rates change or due to increased competition. In addition, deterioration of the credit markets generally may cause an adverse impact in a broad range of markets, including U.S. and international credit and interbank money markets generally, thereby affecting a wide range of financial institutions and markets. Certain events in the financial sector may cause an unusually high degree of volatility in the financial markets, both domestic and foreign, and cause certain financial services companies to incur large losses. Securities of financial services companies may experience a dramatic decline in value when such companies experience substantial declines in the valuations of their assets, take action to raise capital (such as the issuance of debt or equity securities), or cease operations. Credit losses resulting from financial difficulties of borrowers and financial losses associated with investment activities can negatively impact the sector. Insurance companies may be subject to severe price competition. Adverse economic, business or political developments could adversely affect financial institutions engaged in mortgage finance or other lending or investing activities directly or indirectly connected to the value of real estate.

Geographic Focus Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund). The performance of a fund that is less diversified across countries or geographic regions will be closely tied to market, currency, economic, political, environmental, or regulatory conditions and developments in the countries or regions in which the fund invests, and may be more volatile than the performance of a more geographically-diversified fund.

Europe. The Economic and Monetary Union of the EU requires compliance with restrictions on inflation rates, deficits, interest rates, debt levels and fiscal and monetary controls, each of which may significantly affect every country in Europe. Decreasing imports or exports, changes in governmental or EU regulations on trade, changes in the exchange rate of the euro (the common currency of certain EU countries), the default or threat of default by an EU member country on its sovereign debt, and/or an economic recession in an EU member country may have a significant adverse effect on the economies of EU member countries and their trading partners. The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns or rising government debt levels in several European countries, including Greece, Ireland, Italy, Portugal and Spain. These events have adversely affected the exchange rate of the euro and may continue to significantly affect every country in Europe, including countries that do not use the euro.

Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not produce the desired results, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and other entities of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. In addition, one or more countries may abandon the euro and/or withdraw from the EU. For example, on January 31, 2020, the United Kingdom formally withdrew from the EU (commonly referred to as “Brexit”) and, after a transition period, left the EU single market and customs union under the terms of a new trade agreement on December 31, 2020. The agreement governs the new relationship between the United Kingdom and EU with respect to trading goods and services, but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. The full scope and nature of the consequences of the exit are not at this time known and are unlikely to be known for a significant period of time. It is also unknown whether the United Kingdom's exit will increase the likelihood of other countries also departing the EU. Any exits from the EU, or the possibility of such exits, may have a significant impact on the United Kingdom, Europe, and global economies, which may result

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in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for such economies that could potentially have an adverse effect on the value of the Fund's investments. In addition, a number of countries in Europe have suffered terrorist attacks and additional attacks may occur in the future. Such attacks may cause uncertainty in financial markets and may adversely affect the performance of the issuers to which the Fund has exposure.

Japan. The growth of Japan's economy has historically lagged that of its Asian neighbors and other major developed economies. The Japanese economy is heavily dependent on international trade and has been adversely affected by trade tariffs, other protectionist measures, competition from emerging economies and the economic conditions of its trading partners. China has become an important trading partner with Japan, yet the countries' political relationship has become strained. Should political tension increase, it could adversely affect the economy, especially the export sector, and destabilize the region as a whole. Japan also remains heavily dependent on oil imports, and higher commodity prices could therefore have a negative impact on the economy. The Japanese economy faces several other concerns, including a financial system with large levels of nonperforming loans, over-leveraged corporate balance sheets, extensive cross-ownership by major corporations, a changing corporate governance structure, and large government deficits. These issues may cause a slowdown of the Japanese economy. The Japanese yen has fluctuated widely at times and any increase in its value may cause a decline in exports that could weaken the Japanese economy. Japan has, in the past, intervened in the currency markets to attempt to maintain or reduce the value of the yen. Japanese intervention in the currency markets could cause the value of the yen to fluctuate sharply and unpredictably and could cause losses to investors. Japan has an aging workforce and has experienced a significant population decline in recent years. Japan's labor market appears to be undergoing fundamental structural changes, as a labor market traditionally accustomed to lifetime employment adjusts to meet the need for increased labor mobility, which may adversely affect Japan's economic competitiveness.

The nuclear power plant catastrophe in Japan in March 2011 may have long-term effects on the Japanese economy and its nuclear energy industry. Natural disasters, such as earthquakes, volcanoes, typhoons or tsunamis, could occur in Japan or surrounding areas and could negatively affect the Japanese economy and, in turn, a Fund.

United Kingdom. The United Kingdom has one of the largest economies in Europe, and the United States and other European countries are substantial trading partners of the United Kingdom. As a result, the British economy may be impacted by changes to the economic condition of the United States and other European countries. The British economy, along with certain other EU economies, experienced a significant economic slowdown during the recent financial crisis, and certain British financial institutions suffered significant losses, were severely under-capitalized and required government intervention to survive. The British economy relies heavily on the export of financial services to the United States and other European countries and, therefore, a prolonged slowdown in the financial services sector may have a negative impact on the British economy. Continued governmental involvement or control in certain sectors may stifle competition in certain sectors or cause adverse effects on economic growth. In the past, the United Kingdom has been a target of terrorism. Acts of terrorism in the United Kingdom or against British interests abroad may cause uncertainty in the British financial markets and adversely affect the performance of the issuers to which a Fund has exposure.

Health Care Sector Risk (principal risk for the Equity 500 Index Fund). Companies in the health care sector are subject to extensive government regulation and their profitability can be significantly affected by restrictions on government reimbursement for medical expenses, rising costs of medical products and services, pricing pressure (including price discounting), limited product lines and an increased emphasis on the delivery of healthcare through outpatient services. Companies in the health care sector are heavily dependent on obtaining and defending patents, which may be time consuming and costly, and the expiration of patents may also adversely affect the profitability of these companies. Health care companies are also subject to extensive litigation based on product liability and similar claims. In addition, their products can become obsolete due to industry innovation, changes in technologies or other market developments. Many new products in the health care sector require significant research and development and may be subject to regulatory approvals, all of which may be time consuming and costly with no guarantee that any product will come to market.

Income Risk (principal risk for the Aggregate Bond Index Fund). A Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by a Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Fund may limit the Fund's ability to achieve its objective.

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Indexing Strategy/Index Tracking Risk. Each Fund is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities. Each Fund will seek to replicate Index returns, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. Each Fund generally will buy and will not sell a security included in the Index as long as the security is part of the Index regardless of any sudden or material decline in value or foreseeable material decline in value of the security, even though the Adviser may make a different investment decision for other actively managed accounts or portfolios that hold the security. As a result, a Fund's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index (in absolute terms and by comparison with other indices) and, consequently, the performance, volatility, and risk of a Fund. Errors in index data, index computations or the construction of the Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on a Fund and its shareholders. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), a Fund's return may not match the return of the Index for a number of reasons. For example, the return on the sample of securities purchased by a Fund (or the return on securities not included in the Index) to replicate the performance of the Index may not correlate precisely with the return of the Index. Each Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, a Fund may not be fully invested at times, either as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to track the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between a Fund's return and that of the Index. Changes in the composition of the Index and regulatory requirements also may impact a Fund's ability to match the return of the Index. The Adviser may apply one or more “screens” or investment techniques to refine or limit the number or types of issuers included in the Index in which a Fund may invest. Application of such screens or techniques may result in investment performance below that of the Index and may not produce results expected by the Adviser. Index tracking risk may be heightened during times of increased market volatility or other unusual market conditions.

Industrial Sector Risk(principal risk for the Small/Mid Cap Equity Index Fund). Industrial companies are affected by supply and demand both for their specific product or service and for industrial sector products in general. Government regulation, world events, exchange rates and economic conditions, technological developments and liabilities for environmental damage and general civil liabilities will likewise affect the performance of these companies. Aerospace and defense companies, a component of the industrial sector, can be significantly affected by government spending policies because companies involved in this industry rely, to a significant extent, on U.S. and foreign government demand for their products and services. Thus, the financial condition of, and investor interest in, aerospace and defense companies are heavily influenced by governmental defense spending policies which are typically under pressure from efforts to control the U.S. (and other) government budgets. Transportation securities, a component of the industrial sector, are cyclical and have occasional sharp price movements which may result from changes in the economy, fuel prices, labor agreements and insurance costs.

Inflation Risk (principal risk for the Aggregate Bond Index Fund). Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the values of a Fund's assets can decline. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that domestic or global economic policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to Fund investors or adversely affect the real value of shareholders' investments in the Fund.

Information Technology Sector Risk (principal risk for the Equity 500 Index Fund and Small/Mid Cap Equity Index Fund). Market or economic factors impacting information technology companies could have a major effect on the value of the Fund's investments. The value of stocks of information technology companies is particularly vulnerable to rapid changes in technology product cycles, rapid product obsolescence, government regulation and competition, both domestically and internationally, including competition from foreign competitors with lower production costs. Like other technology companies, information technology companies may have limited product lines, markets, financial resources or personnel. Stocks of technology companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Information technology companies are heavily dependent on patent and intellectual property rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

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Interest Rate Risk (principal risk for the Aggregate Bond Index Fund). Interest rate risk is the risk that the securities held by a Fund will decline in value because of increases in market interest rates. Duration is a measure used to determine the sensitivity of a security's price to changes in interest rates. Debt securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than debt securities with shorter durations. For example, the value of a security with a duration of five years would be expected to decrease by 5% for every 1% increase in interest rates. Falling interest rates also create the potential for a decline in a Fund's income and yield. Interest-only and principal-only securities are especially sensitive to interest rate changes, which can affect not only their prices but can also change the income flows and repayment assumptions about those investments. Variable and floating rate securities also generally increase or decrease in value in response to changes in interest rates, although generally to a lesser degree than fixed-rate securities. A substantial increase in interest rates may also have an adverse impact on the liquidity of a security, especially those with longer durations. Changes in governmental policy, including changes in central bank monetary policy, could cause interest rates to rise rapidly, or cause investors to expect a rapid rise in interest rates. This could lead to heightened levels of interest rate, volatility and liquidity risks for the fixed income markets generally and could have a substantial and immediate effect on the values of a Fund's investments.

Large-Capitalization Securities Risk (principal risk for the Equity 500 Index Fund and the Global All Cap Equity ex-U.S. Index Fund). Securities issued by large-capitalization companies may present risks not present in smaller companies. For example, larger companies may be unable to respond as quickly as smaller and mid-sized companies to competitive challenges or to changes in business, product, financial, or other market conditions. Larger companies may not be able to maintain growth at the high rates that may be achieved by well-managed smaller and mid-sized companies, especially during strong economic periods. Returns on investments in securities of large companies could trail the returns on investments in securities of smaller and mid-sized companies.

Large Shareholder Risk. To the extent a large proportion of the shares of a Portfolio are highly concentrated or held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, a Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of a Portfolio to conduct its investment program. For example, they could require a Portfolio to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to shareholders, or a Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case a Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. A Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Leveraging Risk. Borrowing transactions, reverse repurchase agreements, certain derivatives transactions, securities lending transactions and other investment transactions such as when-issued, delayed-delivery, or forward commitment transactions may create investment leverage. If a Fund engages in transactions that have a leveraging effect on the Fund's investment portfolio, the value of the Fund will be potentially more volatile and all other risks will tend to be compounded. This is because leverage generally creates investment risk with respect to a larger base of assets than a Fund would otherwise have and so magnifies the effect of any increase or decrease in the value of the Fund's underlying assets. The use of leverage is considered to be a speculative investment practice and may result in losses to a Fund. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The use of leverage may cause a Fund to liquidate positions when it may not be advantageous to do so to satisfy repayment, interest payment, or margin obligations or to meet asset segregation or coverage requirements.

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elimination of LIBOR may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include “fall back” provisions addressing the transition from LIBOR. Uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by a Fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to a Fund.

Liquidity Risk. Liquidity risk is the risk that a Fund may not be able to dispose of investments or close out derivatives transactions readily at a favorable time or prices (or at all) or at prices approximating those at which a Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity a Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

The term “illiquid investments” for this purpose means securities that a Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the securities. If any Fund determines at any time that it owns illiquid investments in excess of 15% of its net assets, it will cease to undertake new commitments to acquire illiquid securities until its holdings are no longer in excess of 15% of its NAV, report the occurrence in compliance with Rule 30b1-10 under the 1940 Act and, depending on circumstances, may take additional steps to reduce its holdings of illiquid securities.

Market Disruption and Geopolitical Risk. A Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of a Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Fund's investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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Market Risk. Market prices of investments held by a Fund will go up or down, sometimes rapidly or unpredictably. A Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile, and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in actual or perceived creditworthiness of issuers and general market liquidity. Even if general economic conditions do not change, the value of an investment in a Fund could decline if the particular industries, sectors or companies in which the Fund invests do not perform well or are adversely affected by events. Further, legal, political, regulatory and tax changes also may cause fluctuations in markets and securities prices. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on a Fund and its investments.

An outbreak of a respiratory disease caused by a novel coronavirus (known as COVID-19) first detected in China in December 2019 has resulted in a global pandemic and major disruptions to economies and markets around the world, including the United States. Although the long-term economic fallout of COVID-19 is difficult to predict, it has contributed to, and may continue to contribute to, market volatility, inflation and systemic economic weakness, and trading in many instruments was and may continue to be disrupted as a result. Liquidity for many instruments was and may continue to be greatly reduced for periods of time. Some interest rates have been very low and in some cases yields are negative. Governments and central banks, including the Federal Reserve in the United States, have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. The impact of these measures, and whether they will be effective to mitigate the economic and market disruption, will not be known for some time. The foregoing could result in disruptions to the services provided to a Fund by its service providers.

Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject a Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and a Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Master/Feeder Structure Risk. Each Fund pursues its objective by investing substantially all of its assets in another pooled investment vehicle (a “master fund”). The ability of a Fund to meet its investment objective is directly related to the ability of the master fund to meet its investment objective. The ability of a Fund to meet its objective may be adversely affected by the purchase and redemption activities of other investors in the master fund. The ability of a Fund to meet redemption requests will depend on its ability to redeem its interest in the master fund. The Adviser or an affiliate serves as investment adviser to the master fund, leading to potential conflicts of interest. For example, the Adviser or its affiliates will receive fees based on the amount of assets invested in the master fund. Investment by a Fund in the master fund may be beneficial in the management of the master fund, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a master fund sponsored or managed by the Adviser or its affiliates in lieu of investments by a Fund directly in portfolio securities, or may have an incentive to invest in such master fund over a master fund sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a master fund sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a master fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so. A Fund will bear its pro rata portion of the expenses incurred by the master fund.

Mortgage-Related and Other Asset-Backed Securities Risk (principal risk for the Aggregate Bond Index Fund). Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically structured like mortgage-related securities,

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but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

In a “forward roll” transaction, a Fund will sell a mortgage-related security to a bank or other permitted entity and simultaneously agree to purchase a similar security from the institution at a later date at an agreed upon price. The mortgage securities that are purchased will bear the same interest rate as those sold, but generally will be collateralized by different pools of mortgages with different prepayment histories than those sold. The values of such transactions will be affected by many of the same factors that affect the values of mortgage-related securities generally. In addition, forward roll transactions may have the effect of creating investment leverage in a Fund.

Non-U.S. Securities Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund). Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Because non-U.S. securities are typically denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets, to the extent they are non-U.S. dollar denominated, may be affected favorably or unfavorably by currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Fund invests could cause the Fund's investments in that country to experience gains or losses.

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Reinvestment Risk (principal risk for the Aggregate Bond Index Fund). Income from a Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by a Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

Risk of Investment in Other Pools. If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Settlement Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund). Markets in different countries have different clearance and settlement procedures and in certain markets there have been times when settlements have been unable to keep pace with the volume of transactions. Delays in settlement may increase credit risk to a Fund, limit the ability of a Fund to reinvest the proceeds of a sale of securities, hinder the ability of a Fund to lend its portfolio securities, and potentially subject a Fund to penalties for its failure to deliver to on-purchasers of securities whose delivery to a Fund was delayed. Delays in the settlement of securities purchased by a Fund may limit the ability of a Fund to sell those securities at times and prices it considers desirable, and may subject a Fund to losses and costs due to its own inability to settle with subsequent purchasers of the securities from it. A Fund may be required to borrow monies it had otherwise expected to receive in connection with the settlement of securities sold by it, in order to meet its obligations to others. Limits on the ability of a Fund to purchase or sell securities due to settlement delays could increase any variance between a Fund's performance and that of its benchmark index.

Small-, Mid- and Micro-Capitalization Securities Risk (principal risk for the Global All Cap Equity ex-U.S. Index Fund and Small/Mid Cap Equity Index Fund). The securities of small-, mid- and micro-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of smaller companies may trade less frequently and in smaller volumes than more widely held securities. The prices of these securities may fluctuate more sharply than those of other securities, and a Fund may experience some difficulty in establishing or closing out positions in these securities at prevailing market prices. There may be less publicly available information about the issuers of these securities or less market interest in these securities than in the case of larger companies, both of which can cause significant price volatility. Some securities of smaller issuers may be illiquid or may be restricted as to resale. A Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet a Fund's obligations. Returns on investments in securities of small-, mid- and micro-capitalization companies could trail the returns on investments in securities of larger companies.

Special Risk Considerations of Investing in China (principal risk for the Global All Cap Equity ex-U.S. Index Fund). Investing in securities of Chinese issuers, including by investing in A Shares, involves certain risks and considerations not typically associated with investing in securities of U.S. issuers, including, among others, (i) more frequent (and potentially widespread) trading suspensions and U.S. or foreign government interventions or restrictions with respect to Chi-

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nese issuers, which could preclude the Fund from making certain investments or result in the Fund selling investments at disadvantageous times and which may also cause reduced liquidity and increased price volatility in such investments, (ii) the nature and extent of intervention by the Chinese government in the Chinese securities markets, whether such intervention will continue and the impact of such intervention or its discontinuation, (iii) the risk of nationalization or expropriation of assets, (iv) the risk that the Chinese government may decide not to continue to support economic reform programs, (v) limitations on the use of brokers, (vi) potentially higher rates of inflation, (vii) the unavailability of consistently-reliable economic data, (viii) the relatively small size and absence of operating history of many Chinese companies, (ix) accounting, auditing and financial reporting standards in China are different from U.S. standards and, therefore, disclosure of certain material information may not be available, (x) greater political, economic, social, legal and tax-related uncertainty, (xi) higher market volatility caused by any potential regional territorial conflicts or natural disasters, (xii) higher dependence on exports and international trade, (xiii) the risk of increased trade tariffs, sanctions, embargoes and other trade limitations, (xiv) restrictions on foreign ownership, and (xv) custody risks associated with investing through programs to access Chinese securities. Significant portions of the Chinese securities markets may become rapidly illiquid, as Chinese issuers have the ability to suspend the trading of their equity securities, and have shown a willingness to exercise that option in response to market volatility and other events. The liquidity of Chinese securities may shrink or disappear suddenly and without warning as a result of adverse economic, market or political events, or adverse investor perceptions, whether or not accurate.

Unconstrained Sector Risk. A Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. When a Fund focuses its investments in a particular industry or sector, financial, economic, business, and other developments affecting issuers in that industry, market, or economic sector will have a greater effect on the Fund than if it had not focused its assets in that industry, market, or economic sector, which may increase the volatility of the Fund. Any such investment focus may also limit the liquidity of the Fund. In addition, investors may buy or sell substantial amounts of the Fund's shares in response to factors affecting or expected to affect an industry, market, or economic sector in which the Fund focuses its investments, resulting in extreme inflows or outflows of cash into and out of the Fund. Such extreme cash inflows or outflows might affect management of the Fund adversely.

U.S. Government Securities Risk (principal risk for the Aggregate Bond Index Fund). U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor supported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of a Fund's investments.

Valuation Risk (principal risk for the Aggregate Bond Index Fund, Global All Cap Equity ex-U.S. Index Fund and Small/Mid Cap Equity Index Fund). Some portfolio holdings, potentially a large portion of a Fund's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. Technological issues or other service disruption issues involving third-party service providers may cause a Fund to value its investments incorrectly. In addition, there is no assurance that a Fund could sell or close out a portfolio position for the value established for it at

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any time, and it is possible that a Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by a Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

When-Issued, TBA and Delayed Delivery Securities Risk (principal risk for the Aggregate Bond Index Fund). A Fund may purchase securities on a when-issued, TBA or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. The prices of the securities so purchased or sold are subject to market fluctuations. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of a Fund's net asset value. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose a Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Additional Information About Non-Principal Investment Strategies and Risks

Conflicts of Interest Risk. An investment in a Fund will be subject to a number of actual or potential conflicts of interest. For example, the Adviser or its affiliates may provide services to a Fund, such as securities lending agency services, custodial, administrative, bookkeeping, and accounting services, transfer agency and shareholder servicing, securities brokerage services, and other services for which the Fund would compensate the Adviser and/or such affiliates. The Funds may invest in other pooled investment vehicles sponsored, managed, or otherwise affiliated with the Adviser. There is no assurance that the rates at which a Fund pays fees or expenses to the Adviser or its affiliates, or the terms on which it enters into transactions with the Adviser or its affiliates will be the most favorable available in the market generally or as favorable as the rates the Adviser or its affiliates make available to other clients. Because of its financial interest, the Adviser will have an incentive to enter into transactions or arrangements on behalf of a Fund with itself or its affiliates in circumstances where it might not have done so in the absence of that interest, provided that the Adviser will comply with applicable regulatory requirements.

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Funds. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for a Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by a Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Funds) or otherwise using such information for the benefit of its clients or itself.

The foregoing does not purport to be a comprehensive list or complete explanation of all potential conflicts of interests which may affect a Fund. A Fund may encounter circumstances, or enter into transactions, in which conflicts of interest that are not listed or discussed above may arise.

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Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

Index Construction Risk. A security included in an Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Fund's holdings may not exhibit returns consistent with that characteristic or exposure.

Index Licensing Risk. It is possible that the license under which the Adviser or a Fund is permitted to replicate or otherwise use an Index will be terminated or may be disputed, impaired or cease to remain in effect. In such a case, the Adviser may be required to replace the Index with another index which it considers to be appropriate in light of the investment strategy of a Fund. The use of any such substitute index may have an adverse impact on a Fund's performance. In the event that the Adviser is unable to identify a suitable replacement for the Index, it may determine to terminate a Fund.

Money Market Risk. An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Certain money market funds seek to preserve the value of their shares at $1.00 per share, although there can be no assurance that they will do so, and it is possible to lose money by investing in such a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause the share price of such a money market fund to fall below $1.00. It is possible that such a money market fund will issue and redeem shares at $1.00 per share at times when the fair value of the money market fund's portfolio per share is more or less than $1.00. The SEC has proposed amendments to money market fund regulation that if adopted as proposed would, among other things, increase the daily and weekly liquid asset requirements, remove liquidity fees and redemption gate provisions and require institutional prime money market funds to use swing pricing. Such amendments may, if adopted, limit the Funds' investment flexibility and reduce its ability to generate returns. None of State Street Corporation, State Street Bank and Trust Company (“State Street”), State Street Global Advisors (“SSGA”), SSGA FM or their affiliates (“State Street Entities”) guarantee the value of an investment in a money market fund at $1.00 per share. Investors should have no expectation of capital support to a money market fund from State Street Entities. Other money market funds price and transact at a “floating” NAV that will fluctuate along with changes in the market-based value of fund assets. Shares sold utilizing a floating NAV may be worth more or less than their original purchase price. Recent changes in the regulation of money market funds may affect the operations and structures of money market funds. A money market fund may be permitted or required to impose redemption fees or to impose limitations on redemptions during periods of high illiquidity in the markets for the investments held by it.

Portfolio Turnover Risk (risk for the Aggregate Bond Index Fund). A Fund may engage in frequent trading of its portfolio securities. Fund turnover generally involves a number of direct and indirect costs and expenses to a Fund, including, for example, brokerage commissions, dealer mark-ups and bid/asked spreads, and transaction costs on the sale of securi-

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ties and reinvestment in other securities. The costs related to increased portfolio turnover have the effect of reducing a Fund's investment return, and the sale of securities by a Fund may result in the realization of taxable capital gains, including short-term capital gains, which are taxed to individuals as ordinary income.

Securities Lending Risk. Each Fund may lend portfolio securities in an amount not to exceed 40% of the value of its net assets. For these purposes, net assets shall exclude the value of all assets received as collateral for the loan. Such loans may be terminated at any time. Any such loans must be continuously secured by collateral (either cash or other obligations as may be permitted under the Funds' securities lending program) maintained on a current basis in an amount at least equal to the market value of the securities loaned by a Fund, marked to market each trading day. In a loan transaction, as compensation for lending its securities, a Fund will receive a portion of the dividends or interest accrued on the securities held as collateral or, in the case of cash collateral, a portion of the income from the investment of such cash. In addition, a Fund will receive the amount of all dividends, interest and other distributions on the loaned securities. However, the borrower has the right to vote the loaned securities. A Fund will call loans to vote proxies if a material issue affecting the investment is to be voted upon. Efforts to recall such securities promptly may be unsuccessful, especially for foreign securities or thinly traded securities, and may involve expenses to a Fund. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. Should the borrower of the securities fail financially, a Fund may experience delays in recovering the securities or exercising its rights in the collateral. Loans are made only to borrowers that are deemed by the securities lending agent to be of good financial standing. In a loan transaction, a Fund will also bear the risk of any decline in value of securities acquired with cash collateral. Each Fund expects to invest cash collateral in a pooled investment vehicle advised by the Adviser. With respect to index funds, to the extent the collateral provided or investments made with cash collateral differ from securities included in the relevant Index, such collateral or investments may have a greater risk of loss than the securities included in the Index. In addition, a Fund will be subject to the risk that any income generated by reinvesting cash collateral is lower than any fees the Fund has agreed to pay a borrower.

Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Each Fund is a separate, diversified series of the State Street Institutional Investment Trust (the “Trust”), which is an open-end management investment company organized as a business trust under the laws of the Commonwealth of Massachusetts.

Each Fund invests as part of a “master/feeder” structure. Each Fund currently seeks to achieve its investment objective by investing substantially all of its investable assets in a corresponding Portfolio, a separate mutual fund, that has substantially identical investment objective, investment policies, and risks as the Fund. All discussions about a Fund's investment objective, policies and risks should be understood to refer also to the investment objectives, policies and risks of the corresponding Portfolio.

Each Portfolio's shares are offered exclusively to investors (including without limitation, registered investment companies, private investment pools, bank collective funds, and investment separate accounts) that, like the Fund, pay fees to SSGA FM or its affiliates. The fees paid by those investment vehicles to SSGA FM (or its affiliates) vary depending on a number of factors, including by way of example, the services provided, the risks borne by SSGA FM (or its affiliates), fee rates paid by competitive investment vehicles, and in some cases direct negotiation with investors in the Portfolio.

A Fund can withdraw its investment in a Portfolio if, at any time, the Fund's Board of Trustees determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives of the corresponding Portfolio changed so that they were inconsistent with the objectives of the Fund. If a Fund withdraws its investment from a Portfolio, the Fund may invest all of its assets in another mutual fund that has the same investment objective as the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

SSGA FM serves as the investment adviser to each Fund and corresponding Portfolio and, subject to the oversight of the Board, is responsible for the investment management of each Fund. The Adviser provides an investment management program for each Fund and manages the investment of each Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the U.S. Securities and Exchange Commission (“SEC”) under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

Each Fund has entered into an investment advisory agreement with the Adviser, pursuant to which the Adviser will manage the Fund's assets, for compensation paid at an annual rate of 0.025% of the Aggregate Bond Index Fund's average daily net assets, 0.02% of the Equity 500 Index Fund's average daily net assets, 0.06% of the Global All Cap Equity ex-U.S. Index Fund's average daily net assets and 0.03% of the Small/Mid Cap Equity Index Fund's average daily net assets. For the year ended December 31, 2021, Equity 500 Index Fund's effective management fee paid was 0.00%, Aggregate Bond Fund's effective management fee paid was 0.00%, Global All Cap Equity ex-U.S. Index Fund's effective management fee paid was 0.00%, and Small/Mid Cap Equity Index Fund's effective management fee paid was 0.00%, each as a percentage of the Fund's average daily net assets. The Portfolios pay no investment advisory fees to SSGA FM.

Total Annual Fund Operating Expense Waivers. SSGA FM, as the investment adviser to each of the Equity 500 Index Fund, the Aggregate Bond Index Fund and the Small/Mid Cap Equity Index Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by a Fund, and/or (ii) to reimburse a Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing and sub-transfer agency fees) exceed average daily net assets on an annual basis of 0.02% for the Equity 500 Index Fund, 0.025% for the Aggregate Bond Index Fund and 0.045% for the Small/Mid Cap Equity Index Fund. SSGA FM, as the investment adviser to the Global All Cap Equity ex-U.S. Index Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund

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fees, any class-specific expenses such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed average daily net assets on an annual basis of 0.015% for the Global All Cap Equity ex-U.S. Index Fund. These waiver and/or reimbursement agreements may not be terminated prior to April 30, 2023 except with approval of the Funds' Board of Trustees.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

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Portfolio Management

The Adviser manages the Funds and the Portfolios using a team of investment professionals. The team approach is used to create an environment that encourages the flow of investment ideas. The portfolio managers within the team work together in a cohesive manner to develop and enhance techniques that drive the investment process for the respective investment strategy. This approach requires portfolio managers to share a variety of responsibilities, including investment strategy and analysis, while retaining responsibility for the implementation of the strategy within any particular portfolio. The approach also enables the team to draw upon the resources of other groups within SSGA. Each portfolio management team is overseen by the SSGA Investment Committee.

The table below identifies the professionals primarily responsible for the day-to-day management of each Fund and Portfolio:

Portfolio Managers		Portfolios and Funds
Michael Feehily, Karl Schneider and Amy Scofield		Equity 500 Index Fund and Equity 500 Index II Portfolio
Marc DiCosimo and Joanna Madden		Aggregate Bond Index Fund and Aggregate Bond Index Portfolio
Michael Feehily, Olga Winner and Karl Schneider		Global All Cap Equity ex-U.S. Index Fund and Global All Cap Equity ex-U.S. Index Portfolio
Michael Feehily, Ted Janowsky and Karl Schneider		Small/Mid Cap Equity Index Fund and Small/Mid Cap Equity Index Portfolio

Marc DiCosimo, CFA, is a Vice President of SSGA and the Adviser and a Senior Portfolio Manager in the Fixed Income Beta Solutions Group within the Fixed Income, Cash and Currency Team. Prior to joining SSGA in 2013, Mr. DiCosimo worked at Wellington Management as a fixed income portfolio analyst on the Mortgage Backed Securities Team. Mr. DiCosimo has twenty years of fixed income experience working at Loomis Sayles and Saxon Mortgage Capital. Mr. DiCosimo graduated from the University of Richmond with a degree in Accounting. He is a Chartered Financial Analyst (CFA) and is a member of the CFA Institute and CFA Society Boston, Inc. He is a co-chair of the Mortgage Securitization Council of the Association of Institutional Investors.

Michael Feehily, CFA, is a Senior Managing Director of SSGA and the Adviser and the Head of Global Equity Beta Solutions in the Americas. He is also a member of the Senior Leadership Team and is a voting member on the firm's Trade Management Oversight Committee and the North America Product Committee. In his current role, Mr. Feehily is responsible for overseeing the Global Equity Beta Solutions portfolio management team in the Boston office and helping lead the strategic direction of the business. In addition, he contributes to developing new business opportunities, consulting with clients, and running day-to-day business operations. Mr. Feehily rejoined SSGA in 2010 after spending four years in State Street Global Markets, LLC, where he helped to build the Global Exposure Solutions business. This group created and managed portfolios that were designed to meet the short-term market exposure needs of institutional clients. Prior to this, Mr. Feehily had been Head of the U.S. Passive Equity Team within SSGA, which he originally joined in 1997. He began his career at State Street in 1993 within the Global Services division, where he was a member of the Performance & Analytics team and was one of the founding members of the firm's Private Edge business, which helped to analyze clients' private market investments such as venture capital, corporate finance, and real estate. Mr. Feehily received a Bachelor of Science from Babson College in Finance, Investments, and Economics. He received a Master of Business Administration in Finance from Bentley College and also earned the Chartered Financial Analyst (CFA) designation. Mr. Feehily is a member of the CFA Institute and CFA Society Boston, Inc. He is also a former member of the FTSE/Russell Index Client Advisory Board and the S&P Index Advisory Committee. He is registered as an Advising Representative with all Canadian Provincial Securities Commissions under State Street Global Advisor Limited's (Canada) Portfolio Manager registration category. He currently serves as an Executive Sponsor for the Inclusion & Diversity Talent Acquisition Pillar at SSGA.

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Business Administration and a Master of Science in Finance from the Carroll School of Management at Boston College and a Bachelor of Science in Finance from the University of Massachusetts. She also earned the Chartered Financial Analyst (CFA) designation and is a member of CFA Society Boston, Inc.

Ted Janowsky, CFA, is a Vice President of SSGA and the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. In this capacity, he manages a diverse group of equity and derivative-based index portfolios and has played a significant role designing proprietary portfolio management software. Additionally, Mr. Janowsky was head of the portfolio management team of SSGA's Company Stock Group, which manages all fiduciary transactions and company stock investments including employee stock ownership plans, 401(k) plans, defined benefit plans and non-qualified plans. Prior to joining the Global Equity Beta Solutions Group, he worked as an application developer in Investor Technology Services within State Street Corporation. He also worked as a business analyst in State Street's London and Sydney offices. Mr. Janowsky joined SSGA in 2005. Mr. Janowsky holds a Bachelor of Science in Business Administration from Bucknell University and a Master of Business Administration from the Carroll School of Management at Boston College. He has also earned the Chartered Financial Analyst (CFA) designation and is a member of the CFA Institute and CFA Society Boston, Inc.

Joanna Madden is a Vice President of SSGA and the Adviser and a Portfolio Manager in the Fixed Income Beta Solutions Group since 2013. Previously, Ms. Madden was a portfolio manager in the U.S. Cash Management Group responsible for short-term liquidity investments across all the cash and securities lending portfolios managed in Boston. She joined the Boston group in April 2010 after working as a portfolio manager with the London Cash Management Group. Prior to her portfolio management role, she was a product analyst for the London Cash Management Group where she provided analytical and business support. Before joining SSGA in London, Ms. Madden worked as an operations specialist supporting the Boston Cash Management Group. Ms. Madden received a Bachelor of Science in Political Science from Loyola University of Chicago, Illinois.

Karl Schneider, CAIA, is a Managing Director of SSGA and the Adviser and Deputy Head of Global Equity Beta Solutions (GEBS) in the Americas, where he also serves as a Senior Portfolio Manager for a number of the group's passive equity portfolios. Previously within GEBS, he served as a portfolio manager and product specialist for U.S. equity strategies and synthetic beta strategies, including commodities, buy/write, and hedge fund replication. He is also a member of the S&P Dow Jones U.S. Equities Index Advisory Panel. Prior to joining the GEBS group, Mr. Schneider worked as a portfolio manager in SSGA's Currency Management Group, managing both active currency selection and traditional passive hedging overlay portfolios. He joined SSGA in 1997. Mr. Schneider holds a Bachelor of Science in Finance and Investments from Babson College and a Master of Science in Finance from the Carroll School of Management at Boston College. He has earned the Chartered Alternative Investment Analyst (CAIA) designation and is a member of the CAIA Association.

Amy Scofield is a Principal of SSGA and the Adviser and a Portfolio Manager in the Global Equity Beta Solutions Group. She is responsible for the management of various equity index funds, with domestic and international strategies. Ms. Scofield rejoined SSGA in November of 2010, after spending two years at Atlantic Trust Company, a private wealth management firm. In her role at Atlantic Trust Company, she specialized in asset allocation and performance analysis for high net worth clients. Prior to Atlantic Trust Company, Ms. Scofield was a compliance officer at SSGA, where she was responsible for ensuring equity portfolios met specified guidelines. She also worked as an operations associate in SSGA's International Structured Products Group. Ms. Scofield holds a Bachelor of Arts in Economics from Boston College.

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Funds is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

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The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

The Trustees of the Trust oversee generally the operations of the Funds and the Trust. The Trust enters into contractual arrangements with various parties, including, among others, the Funds' investment adviser, custodian, transfer agent, and accountants, who provide services to the Funds. Shareholders are not parties to any such contractual arrangements or intended beneficiaries of those contractual arrangements, and those contractual arrangements are not intended to create in any shareholder any right to enforce them directly against the service providers or to seek any remedy under them directly against the service providers.

This Prospectus provides information concerning the Trust and the Funds that you should consider in determining whether to purchase shares of the Funds. Neither this Prospectus, nor the related SAI, is intended, or should be read, to be or to give rise to an agreement or contract between the Trust or the Funds and any investor, or to give rise to any rights in any shareholder or other person other than any rights under federal or state law that may not be waived.

Shareholder Information

Determination of Net Asset Value

Each Fund determines its NAV per share once each business day as of the scheduled close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in a Fund. The NAV of each class of a Fund's Shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding. As noted in this Prospectus, each Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when each Fund does not price its shares. Consequently, the NAV of each Fund's Shares may change on days when shareholders are not able to purchase or redeem the Fund's Shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. Each Fund values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Funds' Board, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by a Fund occurs after the close of a related exchange but before the determination of a Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent that a Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published NAVs per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

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Investing in State Street Institutional Investment Trust Shares

Mutual funds advised by SSGA FM (the “State Street Funds”) and their service providers have a legal obligation to collect from you certain personal information about you at the time you open an account in order to verify your identity and the source of your payment. If you do not provide this information, you may not be able to open an account with the State Street Funds. If the State Street Funds believe that they have uncovered unlawful activity, the State Street Funds and their service providers may close your account and take any action they deem reasonable or required by law. The State Street Funds reserve the right to reject any purchase order.

This section of the Prospectus explains the basics of doing business with the State Street Funds. Carefully read each topic. The policies set forth below regarding the purchase, redemption and exchange of State Street Fund shares are in addition to the “Purchase and Sale of Fund Shares” section contained in the “Fund Summary” portion of this Prospectus. The State Street Funds reserve the right to change the following policies, without notice to shareholders; except that any modification or termination of the exchange privileges described in this Prospectus will be preceded by 60 days' advance notice to shareholders. Please call or check online for current information. Requests for transactions in the State Street Funds will be processed when they are received in “good order.” “Good order” means that the request is in an accurate and complete form, and all applicable documents have been received in such accurate and complete form (including, typically, a signed application and medallion-guaranteed documents), and, for a purchase request, the check or wired funds have cleared.

Purchasing Shares

Choosing a Share Class

The Funds offer three classes of shares through this Prospectus: Class A, Class I and Class K, available to you subject to the eligibility requirements set forth below.

All classes of a Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. The availability of shares of a particular class through a given Financial Intermediary will depend on the policies and procedures of the Financial Intermediary. The Funds, the Distributor, the Adviser and the Transfer Agent do not provide advice or make recommendations regarding Fund share classes and do not verify that you have invested in the share class most appropriate for your investment needs. You should choose the class with the expense structure that best meets your needs and for which you are eligible. Some factors to consider are the amount you plan to invest, the time period before you expect to sell your shares, whether you might invest more money in the Funds in the future, and the nature of your arrangement with a Financial Intermediary. Your investment professional can help you choose a share class that is appropriate for your investment needs.

When you buy Class A shares, the initial sales load is deducted from the amount you invest, unless you qualify for an initial sales load waiver. This means that less money will be invested in a Fund immediately. Class A shares have a Rule 12b-1 fee of 0.25% per year. A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

The chart below summarizes the features of the different share classes. This chart is only a general summary, and you should read the description of each Fund's expenses in each Fund Summary in this Prospectus.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their families. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

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	Class A	Class I	Class K
Availability	Available to the general public through certain Financial Intermediaries.	Limited to certain investors serviced through a Financial Intermediary receiving a fee from the applicable Fund for shareholder servicing or similar services.	Limited to certain investors, including certain financial institutions, qualified recordkeepers and employer-sponsored retirement plans.
Minimum Initial Investment	$2,000. The investment minimum may be modified, waived or reduced for certain types of investors (e.g., 401(k) or 403(b) plans) and investments as well as for certain fee-based programs where an agreement is in place.	There is no minimum investment for Class I shares.	There is no minimum investment for Class K shares.
Maximum Investment	None.	None.	None.
Initial (Front-End) Sales Charge	Yes. 5.25% for Equity Funds and 3.75% for Fixed Income Funds, payable at time of purchase. Lower sales charges are available for larger investments. See the chart under “Class A” section of this Prospectus.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No, except for purchases of $1,000,000 or more that are redeemed within 18 months after purchase.	No.	No.
Distribution and Service (12b-1) Fees	0.25% annual fee.	No.	No.
Redemption Fees	No.	No.	No.

The following pages cover additional details about each share class, including information about share class eligibility, initial and deferred sales charges, and sales charge reductions and waivers. Information about sales charges and sales charge reductions and waivers is also available free of charge on the Funds' website at www.ssga.com.

Class A

Class A shares are available to the general public for investment through qualified recordkeepers with a distribution and/or fund servicing agreement maintained with SSGA FD.

When you buy Class A shares, you pay an initial (or front-end) sales charge at the time of your investment, which is included in the offering price, unless you qualify for a sales charge reduction or waiver. This fee is deducted from the amount you invest, and the remainder of your money is used to buy shares in the Fund. The tables below show the amount of sales charge you would pay at different levels of investment and the commissions paid to Financial Intermediaries at each level of investment. The actual sales charge you pay may vary slightly from the rates disclosed due to rounding.

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Equity Funds (Equity 500 Index Fund, Global All Cap Equity ex-U.S. Index Fund and Small/Mid Cap Equity Index Fund)

Amount of Purchase Payment	Sales Charge as a % of Offering Price	Sales Charge as a % of Net Amount Invested	Financial Intermediary Compensation as a % of Offering Price
Less than $50,000	5.25%	5.54%	4.75%
$50,000-$99,999	4.50%	4.71%	4.00%
$100,000-$249,999	3.50%	3.63%	3.25%
$250,000-$499,999	2.50%	2.56%	2.25%
$500,000-$999,999	2.00%	2.04%	1.75%
$1,000,000 or more	None	None	Advanced Commission^{1, 2}

Fixed Income Funds (Aggregate Bond Index Fund)

Amount of Purchase Payment	Sales Charge as a % of Offering Price	Sales Charge as a % of Net Amount Invested	Financial Intermediary Compensation as a % of Offering Price
Less than $100,000	3.75%	3.90%	3.25%
$100,000-$249,999	3.25%	3.36%	3.00%
$250,000-$499,999	2.25%	2.30%	2.00%
$500,000-$999,999	1.75%	1.78%	1.50%
$1,000,000 or More	None	None	Advanced Commission^{1, 2}

¹	Class A advanced commission for purchases over $1 million:

1.00%	First $3 million
Plus 0.50%	Next $12 million
Plus 0.25%	Over $15 million

If you purchase $1,000,000 or more of Class A shares of a Fund, you will not be assessed a sales charge at the time of purchase. SSGA FD pays broker-dealers advanced commissions that are calculated on a year-by-year basis based on the amounts invested during that year. Accordingly, with respect to additional purchase amounts, the advanced commission breakpoint resets annually to the first breakpoint on the anniversary of the first purchase. You may be charged a deferred sales charge of 1.00% of the lesser of the original cost of the shares being redeemed or your redemption proceeds if you redeem your shares within 18 months after purchase.

Reducing Your Class A Sales Charge

The Funds offer two principal ways for you to qualify for discounts on initial sales charges on Class A share purchases, often referred to as “breakpoint discounts”: Right of Accumulation or a Letter of Intent. Each of these methods is described below. In taking advantage of these methods for reducing the initial sales charge you will pay, you may link purchases of shares of all of the State Street Funds that offer Class A shares in which you invest (as described below) even if such State Street Funds are held in accounts with different Financial Intermediaries, as well as purchases of Class I and Class N shares of all State Street Funds (other than shares of money market funds) to be held in accounts owned by your spouse or domestic partner and children under the age of 21 who share your residential address. It is your responsibility when investing to inform your Financial Intermediary or the State Street Funds that you would like to have one or more of the State Street Funds linked together for purposes of reducing the initial sales charge.

Right of Accumulation. You may qualify for a reduction in the sales charge you pay for purchases of Class A shares through Right of Accumulation. To calculate the sales charge applicable to your net purchase of Class A shares, you may aggregate your investment calculated as the higher of (a) the current value of your existing holdings or (b) the amount you invested (excluding capital appreciation) less any withdrawals of any Class A, Class I, and Class N shares of a State Street Fund (other than shares of money market funds) held in:

1.	Your account(s);
2.	Account(s) of your spouse or domestic partner;
3.	Account(s) of children under the age of 21 who share your residential address;
4.	Trust accounts established by any of the individuals in items (1) through (3) above. If the person(s) who established the trust is deceased, the trust account may be aggregated with the account(s) of the primary beneficiary of the trust;
5.	Solely controlled business accounts; and
6.	Single-participant retirement plans of any of the individuals in items (1) through (3) above.

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In order to obtain any breakpoint reduction in the initial sales charge, you must, before purchasing Class A shares, inform your Financial Intermediary or the State Street Funds if you have any of the above types of accounts that can be aggregated with your current investment in Class A shares to reduce the applicable sales charge. In order to verify your eligibility for a reduced sales charge, you may be required to provide appropriate documentation, such as an account statement or the social security or tax identification number on an account, so that the State Street Funds may verify (1) the number of shares of the State Street Funds held in your account(s) with State Street Funds, (2) the number of shares of the State Street Funds held in your account(s) with a Financial Intermediary, and (3) the number of shares of the State Street Funds held in an account with a Financial Intermediary owned by your spouse or domestic partner and by children under the age of 21 who share your residential address.

Gifting of Shares. If you make a gift of shares, upon your request, you may combine purchases, if made at the same time, under right of accumulation of Class A, Class I and Class N shares of a State Street Fund (other than any shares of money market funds) at the sales charge discount allowed for the combined purchase. The receiver of the gift may also be entitled to a prospective reduction in sales charges in accordance with the Funds' right of accumulation or other provisions. You or the receiver of the gift must provide certain account information to State Street or their agents at the time of purchase to exercise this right.

Letter of Intent. In order to immediately reduce your Class A sales charge, you may sign a Letter of Intent stating your intention to buy a specified amount of Class A shares of one or more State Street Funds within a 13-month period at the reduced sales charge rates applicable to the aggregate amount of the intended purchases stated in the Letter. Purchases of Class A shares of one or more State Street Funds you make over the 13- month period will be combined and you will pay the same sales charge on the new Class A shares that you would have paid if all shares were purchased at once. The 13-month Letter of Intent period commences on the day that the Letter of Intent is received by the Funds or your Financial Intermediary. Purchases submitted not more than three months prior to the date the Letter of Intent is received are considered in determining the level of sales charge that will be paid pursuant to the Letter of Intent; however, the Letter of Intent will not result in any reduction in the amount of any previously paid sales charge. In addition, investors do not receive credit for shares purchased by the reinvestment of distributions.

The Letter of Intent is a non-binding commitment upon the investor to purchase the full amount indicated. Shares worth 5% of the amount of each purchase will be held in escrow (while remaining in your name) until the full amount covered by the Letter of Intent has been invested. If the terms of the Letter of Intent are not fulfilled by the end of the 13th month, you must pay SSGA FD the difference between the sales charges applicable to the purchases at the time they were made and the reduced sales charges previously paid or SSGA FD will liquidate sufficient escrowed shares to obtain the difference. Calculations made to determine whether a Letter of Intent commitment has been fulfilled will be made on the basis of the amount invested prior to the deduction of the applicable sales charge.

To take advantage of the Right of Accumulation and/or a Letter of Intent, complete the appropriate section of your Account Application or contact your Financial Intermediary. To determine if you are eligible for these programs, call (800) 647-7327. These programs may be terminated or amended at any time.

Waiver Of The Class A Sales Charge

A sales charge (“load”) may not be imposed on Class A shares of the Funds if the shares were:

1.	Acquired through the reinvestment of dividends and capital gain distributions.
2.	Acquired in exchange for shares of another Class A State Street Fund that were previously assessed a sales charge. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares at the same CDSC rate.
3.	Bought in State Street Funds that do not offer Class N (no load) shares¹ by officers, directors or trustees, retirees and employees and their immediate family members (i.e., spouses, domestic partners, children, grandchildren, parents, grandparents, and any dependent of the person, as defined in Section 152 of the Internal Revenue Code of 1986 (the “Code”)) of:

•	The State Street Funds
•	State Street Corporation and its subsidiaries and affiliates

¹	State Street Funds that offer Class N Shares include: State Street Defensive Emerging Markets Equity Fund (SSEMX), State Street International Stock Selection Fund (SSAIX) and State Street S&P 500 Index Fund (SVSPX).

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4.	Bought by employees of:

•

DST Asset Manager Solutions, Inc. and its subsidiaries and affiliates.

•

Financial Intermediaries of financial institutions that have entered into selling agreements with the Funds or SSGA FD and their subsidiaries and affiliates (or otherwise have an arrangement with a Financial Intermediary or financial institution with respect to sales of Fund Shares). This waiver includes the employees' immediate family members (i.e., spouses, domestic partners, children, grandchildren, parents, grandparents and any dependent of the employee, as defined in Section 152 of the Code).

5.	Bought by:

•	Authorized retirement plans serviced or sponsored by a Financial Intermediary, provided that such Financial Intermediary has entered into an agreement with SSGA FD or with the Fund with respect to such purchases at NAV.
•	Investors who are directly rolling over or transferring shares from an established State Street Fund or State Street qualified retirement plan. Rolling over or transferring shares involves the transferring of shares (in-kind); there is no cash movement associated with the transaction.
•	Clients of Financial Intermediaries that (i) charge an ongoing fee for advisory, management, consulting or similar services, or (ii) have entered into an agreement with SSGA FD to offer Class A shares through a no-load network or platform, or self-directed brokerage accounts that may or may not charge transaction fees to customers.
•	Insurance company separate accounts.
•	Tuition Programs that qualify under Section 529 of the Code.

6.	Bought with proceeds from the sale of Class A shares of a State Street Fund, but only if the purchase is made within 90 days of the sale or distribution. Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.
7.	Bought in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which a Fund is a party. However, you may pay a CDSC when you sell the Fund Shares you received in connection with the plan of reorganization.

Additional Sales Charge Waiver Disclosure

Sales charge waivers are available for eligible purchases of shares made directly though the State Street Funds advised by SSGA FM, and may be available for eligible purchases made through Financial Intermediaries that offer Class A shares on a load-waived basis to you and all similarly situated customers in accordance with the Financial Intermediary's policies and procedures.

Some Financial Intermediaries do not provide all of the sales charge waivers that are available when you purchase shares of the State Street Funds, including sales charge waivers for certain types of accounts, investors, relationships or transactions. Consult your financial advisor to determine which sales charge waivers, if any, you are entitled to receive when purchasing through your Financial Intermediary. You may need to invest directly through another Financial Intermediary in order to take advantage of a specific sales charge waiver offered by a Fund.

Similarly, when purchasing through a Financial Intermediary, your eligibility to receive sales charge waivers and reductions through reinstatement, rights of accumulation and letters of intent depends on the policies and procedures of the Financial Intermediary.

In all instances, it is the purchaser's responsibility to notify SSGA at (800) 647-7327 or the purchaser's Financial Intermediary of any relationship or other facts qualifying the purchaser for sales charge reduction or waivers. Waivers or reductions may be eliminated, modified, and added at any time without providing advance notice to shareholders.

How the CDSC is Calculated

The State Street Funds calculate the CDSC by treating all purchases made in a given month as though they were made on the first day of the month.

The CDSC will be multiplied by then current market value or the original cost of shares being redeemed, whichever is less. To minimize the CDSC, shares not subject to any charge, including share appreciation, or acquired through reinvestment of dividends or capital gain distributions, are redeemed first followed by shares held the longest time.

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You should retain any records necessary to substantiate historical costs because SSGA FD, the Funds, the transfer agent and your Financial Intermediary may not maintain such information.

Waiver of the CDSC

In the following situations, no CDSC is imposed on redemptions of Class A shares of the Funds:

1.	If you participate in the Automatic Withdrawal Plan. Redemptions made on a regular periodic basis (e.g. monthly) will not be subject to any applicable CDSC if they are, in the aggregate, less than or equal to 10% annually of the current market value of the account balance. Redemptions made as part of a required minimum distribution are also included in calculating amounts eligible for this waiver. For information on the Automatic Withdrawal Plan, please see Service Options.
2.	If you are a registered participant or beneficial owner of an account and you die or become disabled (as defined in Section 72(m)(7) of the Code). This waiver is only available for accounts open prior to the shareholder's or beneficiary's death or disability, and the redemption must be made within one year of such event. Subsequent purchases into such account are not eligible for the CDSC waiver. In order to qualify for this waiver, SSGA FD must be notified of such death or disability at the time of the redemption order and be provided with satisfactory evidence of such death or disability.
3.	Redemptions that represent a required minimum distribution from your IRA Account or other qualifying retirement plan but only if you are at least age 72 or age 70 ½ if you reached age 70 ½ prior to January 1, 2020. If you maintain more than one IRA, only the assets credited to the IRA that is invested in one or more of the State Street Funds are considered when calculating that portion of your minimum required distribution that qualifies for the waiver.
4.	A distribution from a qualified retirement plan by reason of the participant's retirement.
5.	Redemptions that are involuntary and result from a failure to maintain the required minimum balance in an account.
6.	Exchanges in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which a Fund is a party. However, you may pay a sales charge when you redeem the Fund Shares you receive in connection with the plan of reorganization.
7.	Exchanges for shares of the same class of another State Street Fund. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares. For purposes of the CDSC, shares will continue to age from the date of the original purchase of the Fund Shares.
8.	Redemption of shares purchased through employer sponsored retirement plans and deferred compensation plans. The CDSC, however, will not be waived if the plan redeems all of the shares that it owns on behalf of participants prior to the applicable CDSC period, as defined above.
9.	Redemptions as part of annual IRA custodial fees.
10.	Acquired through the reinvestment of dividends and capital gains distributions.

Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.

Class A Account Reinstatement Privileges

You may purchase Class A shares at NAV within 90 days of the sale with no sales charge by reinstating all or part of your proceeds into the same account that the sale or distribution occurred. Any applicable CDSC in connection with the redemption in Class A shares will be credited and aging will begin at original purchase date. Please note that a redemption and reinstatement are considered to be a sale and purchase for tax-reporting purposes.

Class I

Class I shares are not subject to any sales charge. Only certain investors are eligible to buy Class I shares. Your Financial Intermediary can help you determine whether you are eligible to purchase Class I shares.

Class I shares are available to the following categories of investors serviced through a Financial Intermediary receiving a fee from a Fund for shareholder servicing or similar services:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) that have entered into agreements with the Fund to purchase Class I shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund “supermarkets”;
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

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2.	Defined contribution, defined benefit and other employer-sponsored employee benefit plans, whether or not qualified under the Code.

There is no minimum investment for Class I shares.

Class K

Class K shares are not subject to any sales charge. Only certain investors are eligible to buy Class K shares. Your Financial Intermediary can help you determine whether you are eligible to purchase Class K shares.

Class K shares are available to the following categories of investors:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) purchasing Fund Shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund "supermarkets";
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Qualified recordkeepers with an applicable agreement maintained with SSGA FD;
3.	Endowments and foundations, and defined contribution, defined benefit, and other employer-sponsored employee benefit plans, whether or not qualified under the Code;
4.	Certain other registered open-end investment companies whose shares are distributed by SSGA FD;
5.	Current or retired Directors or Trustees of the State Street Funds, officers and employees of SSGA, and any of its subsidiaries, such persons' spouses, and children under the age of 21, and trust accounts for which any of such person is a beneficiary;
6.	Qualified state tuition plans described in Section 529 of the Code and donor-advised charitable gift funds (subject to all applicable terms and conditions);
7.	Health Savings Accounts under Section 223 of the Code if such accounts are maintained by the Fund at an omnibus level;
8.	Collective investment trusts.

There is no minimum investment for Class K shares.

How to Initiate a Purchase Request

Investing in the State Street Funds Through a Financial Intermediary

If you currently do not have an account with State Street Funds, you may establish a new account and purchase shares through a Financial Intermediary, such as a bank, broker, or investment adviser. Please consult your Financial Intermediary to determine which, if any, shares are available through that firm and to learn about other rules that may apply. You may also submit a New Account Application. To open certain types of accounts, such as IRAs, you will be required to submit an account-specific application. If you intend to add certain investor services offered by the State Street Funds, such as Automatic Investment and Withdrawals Plans, you also will be required to submit a Service Option Form. See Service Options. If you are opening an account through a Financial Intermediary, such as a bank or broker, the Financial Intermediary should have the documents that you will need.

Account Applications and Other Documents. You may find many of the forms necessary to open an account online or by calling or writing to the State Street Funds. See Contacting the State Street Funds.

Opening Accounts and Purchasing By Telephone. You may call the State Street Funds to request that the account-opening forms be sent to you or for assistance in completing the necessary paperwork. Once an account has been established, you may also call the State Street Funds to request a purchase of shares. See Contacting the State Street Funds.

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Opening Accounts and Purchasing By Mail. You may send the State Street Funds your account registration form and check to open a new account. To add to an existing account, you may send your check with a written request. You also may send a written request to the State Street Funds to make an exchange. For the State Street Funds' addresses, see Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

How to Pay for a Purchase

By Wire. Please call the State Street Funds for instructions and policies on purchasing shares by wire. See Contacting the State Street Funds. All wires should be in U.S. dollars and immediately available funds.

By Check. You may send a check to make initial or additional purchases to your fund account. Make your check payable to “State Street Funds” and include the appropriate fund name and account number (e.g., “State Street Equity 500 Index Fund—a/c #xxx”) in the memo section of the check.

By Exchange. You may purchase shares of a State Street Fund, provided the Funds' minimum investment is met, using the proceeds from the simultaneous redemption of shares of another State Street Fund of the same class. You may initiate an exchange by telephone, or by mail. See Exchanging Shares below.

In-Kind Purchase of State Street Fund Shares. The State Street Funds, in their sole discretion, may permit you to purchase shares of a State Street Fund (“State Street Fund Shares”) through the exchange of other securities that you own. The market value of any securities exchanged, plus any cash, must be at least $25 million. Please consult your tax adviser regarding in-kind transactions. Please contact the State Street Funds for more information, including additional restrictions. See Contacting the State Street Funds.

Trade Dates-Purchases

The trade date for any purchase request received in good order will depend on the day and time the State Street Funds receive your request, the manner in which you are paying, and the type of fund you are purchasing. Each State Street Fund's NAV is calculated only on business days, that is, those days that the NYSE is open for regular trading. Purchase orders are processed at the NAV next determined after the Fund accepts a purchase order.

For Purchases by Check, Exchange or Wire into all Funds: If the purchase request is received in good order by the State Street Funds on a business day before the close of regular trading on the NYSE (ordinarily 4 p.m., Eastern time), the trade date will be the same day. If the purchase request is received in good order on a business day after the close of regular trading on the NYSE, or on a non-business day, the trade date will be the next business day.

If your purchase request is not in good order, it may be rejected.

For further information about purchase transactions, consult our website at www.ssga.com or see Contacting the State Street Funds.

Other Purchase Policies You Should Know

Check Purchases. All checks used to purchase State Street Fund Shares must be drawn on a U.S. bank and in U.S. dollars. The State Street Funds will not accept any third-party check used for an initial purchase of Fund Shares, or any check drawn on a credit card account for any purpose.

New Accounts. We are required by law to obtain from you certain personal information that we will use to verify your identity. If you do not provide the information, we may not be able to open your account. If we are unable to verify your identity, the State Street Funds reserve the right, without notice, to close your account or take such other steps as we deem reasonable.

Refused or Rejected Purchase Requests. The State Street Funds reserve the right to stop selling Fund Shares or to reject any purchase request at any time and without notice, including purchases requested by exchange from another State Street Fund. This right also includes the right to reject any purchase request because of a history of frequent trading by the investor or because the purchase may negatively affect a Fund's operation or performance.

Purchases Through Pension Plans. If you are purchasing State Street Fund Shares through a pension or other participation plan, you should contact your plan administrator for further information on purchases.

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Redeeming Shares

By Telephone. You may call the State Street Funds to request a redemption of shares. See Contacting the State Street Funds.

By Mail. You may send a written request to the State Street Funds to redeem from a Fund account or to make an exchange. See Contacting the State Street Funds.

If you wish to redeem Fund Shares through a Financial Intermediary, please contact that Financial Intermediary directly. Your Financial Intermediary may have different or additional requirements for the processing of redemption orders, or may be closed at times when the Fund is open. Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

Trade Date-Redemptions

The trade date for any redemption request received in good order will depend on the day and time the State Street Funds receive your request in good order and the manner in which you are redeeming.

Your redemption will be executed using the NAV as calculated on the trade date. NAVs are calculated only on days that the NYSE is open for regular trading (a business day). If the redemption request is received in good order by the State Street Funds on a business day before the close of regular trading on the NYSE (ordinarily 4 p.m., Eastern time), the request will be processed the same day using that day's NAV. If the redemption request is received in good order on a business day after the close of regular trading on the NYSE, or on a non-business day, the request will be processed the next business day.

How to Receive Redemption Proceeds

Regardless of the method the Funds use to make a redemption payment, the Funds typically expect to pay out redemption proceeds on the next business day after a redemption request is received in good order. If you purchased State Street Fund Shares by check or an automatic investment program and you elect to redeem shares within 15 days of the purchase, you may experience delays in receiving redemption proceeds. In this case, the State Street Funds generally will postpone sending redemption proceeds until it can verify that the check or automatic investment program investment has been collected, but in no event will this delay exceed 15 days. There will be no such delay for redemptions following purchases paid by federal funds wire or by bank cashier's check, certified check or treasurer's check. The State Street Funds reserve the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect a Fund. The State Street Funds reserve the right to suspend the right of shareholder redemption or postpone the date of payment for more than seven days to the extent permitted by the 1940 Act.

The transfer agent may temporarily delay for more than seven days the disbursement of redemption proceeds from the Fund account of a “Specified Adult” (as defined in Financial Industry Regulatory Authority, Inc. (“FINRA”) Rule 2165) based on a reasonable belief that financial exploitation of the Specified Adult has occurred, is occurring, has been attempted, or will be attempted, subject to certain conditions.

Under normal circumstances, each Fund expects to meet redemption requests by using cash or cash equivalents in its portfolio and/or selling portfolio assets to generate cash. The Funds also may pay redemption proceeds using cash obtained through borrowing arrangements (including under the Funds' line of credit, which is shared across all registered funds advised by SSGA FM (other than money market funds)) that may be available from time to time.

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A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs (including through the realization of taxable gain) to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

During periods of deteriorating or stressed market conditions, when an increased portion of a Fund's portfolio may be comprised of less liquid investments, or during extraordinary or emergency circumstances, a Fund may be more likely to pay redemption proceeds with cash obtained through short-term borrowing arrangements (if available) or by giving you securities.

By Electronic Bank Transfer. You may have the proceeds of a fund redemption sent directly to a designated bank account. To establish the electronic bank transfer option on an account, you must designate a bank account by completing a special form or filling out the appropriate section of your account registration form. After the option is set up on your account, you can redeem shares by electronic bank transfer on a regular schedule (Automatic Withdrawal Plan) or from time to time. Your redemption request can be initiated by telephone, or by mail.

By Wire. When redeeming shares of a State Street Fund, you may instruct the State Street Funds to wire your redemption proceeds ($1,000 minimum) to a previously designated bank account. Shares will be redeemed from the account on the day that the redemption instructions are received in good order. The wire redemption option is not automatic; you must designate a bank account by completing a special form or filling out the appropriate section of your account registration form. The State Street Funds typically do not charge you a fee for wiring redemption proceeds, although it reserves the right to do so. Your bank may charge a fee for receiving a wire. You are encouraged to check with your bank before initiating any transaction.

By Exchange. You may have the proceeds of a State Street Fund redemption invested directly into shares of another State Street Fund of the same class. You may initiate an exchange by telephone, or by mail.

By Check. You may have the proceeds of a State Street Funds redemption paid by check and sent to the address shown on the State Street Funds registration record, provided that the address on the registration record has not changed within thirty (30) days of the redemption request. The State Street Funds will mail you a redemption check, generally payable to all registered account owners.

Other Redemption Policies that You Should Know

Address Changes. If your address of record has been changed within thirty (30) days of the redemption request, the request must be in writing and bear a medallion guarantee.

Significant/Unusual Economic or Market Activity. During periods of significant or unusual economic or market activity, you may encounter delays attempting to give instructions by phone.

Minimum Account Size. If, due to your redemptions or exchanges, your account balance for a Fund falls below a minimum amount set by the Fund (presently, the minimum initial investment of your selected share class), the Fund may choose to redeem the shares in the account and mail you the proceeds. You will receive 60 days' notice that your account will be closed unless an investment is made to increase the account balance to the required minimum. Failure to bring your account balance to the required minimum within the prescribed period may result in the Fund closing your account at the NAV next determined on the day the account is closed, and mailing the proceeds to you at the address shown on the Fund's records.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of one State Street Fund to simultaneously purchase shares of a different State Street Fund. Exchanges may be made within the same class (i.e. Class A shares for Class A shares, Class I shares for Class I shares). Class N shares are also exchangeable for other share classes of State Street Funds and would be subject to the conditions for investing in the other class of shares described in the applicable prospectus. The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares above.

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Exchanges are subject to the terms applicable to the purchases of the Fund into which you are exchanging. Exchange privileges may not be available for all State Street Funds and may be suspended or rejected. Exchanging shares of a State Street Fund for shares of another fund is a taxable event and may result in capital gain or loss. See Tax Considerations below.

If the NYSE is open for regular trading (generally until 4 p.m. Eastern time, on a business day) at the time an exchange request is received in good order, the trade date generally will be the same day. Please note that the State Street Funds reserve the right to revise or terminate the exchange privilege, limit the amount of any exchange, or reject an exchange, at any time, for any reason; provided, that shareholders will be provided 60 days' advance notice of any modification or termination of the exchange privilege.

Share Class Conversions

You may be able to convert your shares to a different share class of the same Fund that has a lower expense ratio provided that you are eligible to buy that share class and that certain conditions are met. This conversion feature is intended for shares held through a Financial Intermediary offering a fee-based or wrap fee program that has an agreement with SSGA FD specific for this purpose. In such instance, your shares may be automatically converted under certain circumstances. Class N shares of a State Street Fund may be converted to Class I shares of the same State Street Fund. Not all share classes are available through all Financial Intermediaries. If your shares of a Fund are converted to a different share class of the same Fund, the transaction will be based on the respective NAV of each class as of the trade date of the conversion. Consequently, you may receive fewer shares or more shares than originally owned, depending on that day's NAVs. The total value of the initially held shares, however, will equal the total value of the converted shares at the time of conversion. The conversion of shares of one class of a Fund into shares of another class of the same Fund is not taxable for U.S. federal income tax purposes and no gain or loss will be reported on the transaction. See the applicable prospectus for share class information. Please contact your Financial Intermediary regarding the tax consequences of any conversion and for additional information.

Frequent-Trading Limits

Frequent, short-term trading, abusive trading practices and market timing (together, “Excessive Trading”), often in response to short-term fluctuations in the market, are not knowingly permitted by the State Street Funds. The State Street Funds do not accommodate frequent purchases and redemptions of Fund Shares by Fund shareholders. Excessive Trading into and out of a State Street Fund may harm a Fund's performance by disrupting portfolio management strategies and by increasing expenses. These expenses are borne by all Fund shareholders, including long-term investors who do not generate such costs.

Excessive Trading activity is generally evaluated based on roundtrip transactions in an account. A “roundtrip” transaction is defined generally as a purchase or exchange into a Fund followed, or preceded, by a redemption or exchange out of the same Fund within 30 days. A State Street Fund may, in its discretion, determine to apply a time period other than 30 days in connection with identifying roundtrip transactions. Shareholders with one or more roundtrip transactions may, in the discretion of a State Street Fund, be blocked from making additional purchases or exchanges in any State Street Fund for a period of time. A State Street Fund has discretion to determine that action is not necessary if it determines that a pattern of trading is not abusive or harmful to the affected Fund in a material way. Fund size and/or transaction size may be considered in evaluating any roundtrip transaction.

The Board of Trustees of the State Street Funds has adopted a “Market Timing/Excessive Trading Policy” (the “Policy”) to discourage Excessive Trading. Under the Policy, the State Street Funds reserve the right to reject any exchanges or purchase orders by any shareholder engaging in Excessive Trading activities.

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;
•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Funds against harmful short-term trading; and

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•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

While the State Street Funds attempt to discourage Excessive Trading, there can be no guarantee that it will be able to identify investors who are engaging in Excessive Trading or limit their trading practices. Additionally, frequent trades of small amounts may not be detected. The State Street Funds recognize that it may not always be able to detect or prevent Excessive Trading or other activity that may disadvantage the Funds or their shareholders.

A State Street Fund shareholder's right to purchase shares through an automatic investment plan or redeem shares in full (or in part through a systematic withdrawal plan) are unaffected by Excessive Trading restrictions.

Service Options

Dividend and Capital Gain Distribution Option

You may set up your State Street Fund account to reinvest any dividend or capital gains distribution that you receive as a Fund shareholder into the same or a different State Street Fund, or have any dividend or capital gain distribution paid by check, by wire or by check to a special payee. No interest will accrue on the amounts represented by the uncashed distribution checks. If you have elected to receive distributions by check, and the postal or other delivery service is unable to deliver the checks because of an incorrect mailing address, or if a distribution check remains uncashed for six months, the uncashed distribution and all future distributions will be reinvested at the then-current NAV of the Fund.

Please refer to Dividends, Distributions and Tax Considerations below for additional information.

Automatic Withdrawal Plan

If your account balance is over $10,000, you may request periodic (monthly, quarterly, semi-annually, or annually) automatic cash withdrawals of $100 or more which can be mailed to you or any person you designate, or sent through ACH to your bank (at your selection). Proceeds from such withdrawals will be transmitted to the bank account you designate two business days after the trade is placed or executed automatically. No interest will accrue on the amounts represented by the uncashed redemption check(s). Ask your financial adviser or Financial Intermediary for details.

Telephone Redemptions and Exchanges

You may set up your State Street Fund account so that if you request over the telephone to redeem State Street Fund Shares, the redemption proceeds will automatically be wired to a designated bank account. You also may set up your account to permit the State Street Funds to act on your telephonic instructions to exchange State Street Funds shares or to establish a systematic exchange plan. You may choose the date, the frequency (monthly, quarterly or annually) of systematic exchanges of your shares in one State Street Fund to another State Street Fund of the same share class.

Automatic Investment Plan

Once the initial investment has been accepted, you may make subsequent investments of $100 or more monthly, quarterly or annually by direct deposit by debiting your bank checking or savings account. Once this option has been established, you may call the State Street Funds to make additional automatic purchases, to change the amount of the existing automatic purchase, or to stop it. Each State Street Fund reserves the right to cancel your automatic investment plan if any correspondence sent by the Fund is returned by the postal or other delivery service as “undeliverable.”

Additional Shareholder Information

Account Transfers

To effect a change in account registration (for example, to add a new joint owner), a shareholder of a State Street Fund may request to open a new account in the same State Street Fund (referred to as a “transfer”). To effect a transfer, the State Street Funds require a completed and signed new account application, including all necessary additional documents required by the form, and a letter of instruction. The letter of instruction must include the name of the State Street Fund and the original account number, and must be signed by all registered owners of the original account and include a medallion guarantee.

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Responsibility for Fraud

The State Street Funds will not be responsible for any account losses because of fraud if we reasonably believe that the person transacting business on an account is authorized to do so. Please take precautions to protect yourself from fraud. Keep your account information private, and immediately review any account statements that we provide to you. It is important that you contact the State Street Funds immediately about any transactions or changes to your account that you believe to be unauthorized.

Right to Change Policies

In addition to the rights expressly stated elsewhere in this Prospectus, the State Street Funds reserve the right, in the future, to:

1.	Alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, service, or privilege at any time;
2.	Accept initial purchases by telephone;
3.	Freeze any account and/or suspend account services if the State Street Funds has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if we reasonably believe a fraudulent transaction may occur or has occurred;
4.	Temporarily freeze any account and/or suspend account services upon initial notification to the State Street Funds of the death of the shareholder until the State Street Funds receive required documentation in good order;
5.	Alter, impose, discontinue, or waive any redemption fee, account service fee, or other fees charged to a group of shareholders; and
6.	Redeem an account or suspend account privileges, without the owner's permission to do so, in cases of threatening conduct or activity the State Street Funds believe to be suspicious, fraudulent, or illegal.

Changes may affect any or all investors. These actions will be taken when, at the sole discretion of the SSGA FM management, we reasonably believe they are deemed to be in the best interest of the State Street Fund.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If the Funds' transfer agent identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to a Fund (if you hold shares directly with a Fund) or to your financial intermediary (if you do not hold shares directly with a Fund).

Dividends, Distributions and Tax Considerations

Dividends of investment income and capital gain distributions of the Funds will be declared and paid at least annually. Any investment income and capital gains that have not been distributed by December of each calendar year are generally distributed at such time. When a Fund distributes investment income or capital gains, the NAV per share is reduced by the amount of the distribution.

Distribution Options. You can choose from four different distribution options as indicated on the application:

•	Reinvestment Option—Dividends and capital gain distributions will be automatically reinvested in additional shares of a Fund. If you do not indicate a choice on the application, this option will be automatically assigned.
•	Income-Earned Option—Capital gain distributions will be automatically reinvested, but a check, direct deposit or wire will be sent for each dividend distribution.
•	Cash Option—A check, wire or direct deposit will be sent for each dividend and capital gain distribution.
•	Direct Dividends Option—Dividends and capital gain distributions will be automatically invested in another identically registered State Street Fund of the same share class.

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If you have elected to receive distributions by check, and the postal or other delivery service is unable to deliver the checks because of an incorrect mailing address, or if a distribution check remains uncashed for six months, the uncashed distribution and all future distributions will be reinvested at the then-current net asset value of the Fund.

Dividend Policy Upon Purchase. A shareholder will receive a dividend or capital gain distribution only if the shareholder purchased Fund Shares by the close of the record date of such dividend or capital gain distribution.

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (800) 647-7327, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Tax Considerations

Each Fund invests substantially all of its assets in a corresponding Portfolio that is expected to be treated as a regulated investment company for federal income tax purposes, and so substantially all of a Fund's income will result from distributions or deemed distributions from the corresponding Portfolio. Therefore, as applicable, and except as otherwise stated, references in this section to the assets owned or income earned by a Fund will include such assets and income of the corresponding Portfolio. Each Fund has elected to be treated as a regulated investment company and intends each year to qualify and to be eligible to be treated as such. A regulated investment company generally is not subject to tax at the corporate level on income and gains that are timely distributed to shareholders. In order to qualify and be eligible for treatment as a regulated investment company, a Fund must, among other things, satisfy diversification, 90% gross income and distribution requirements. A Fund's failure to qualify and be eligible for treatment as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders.

Each Fund generally expects to satisfy the requirements to qualify and be eligible to be treated as a regulated investment company, provided that the respective Portfolio also meets these requirements; each Fund currently expects that the relevant Portfolio will meet these requirements. Because each Fund will invest substantially all its assets in a Portfolio, if such Portfolio were to fail to satisfy the diversification, 90% gross income, or distribution requirement and were not to cure that failure, the Fund itself would be unable to satisfy the diversification requirement. Such a failure to qualify and be eligible for treatment as a regulated investment company could subject the Fund and/or the Portfolio to regular corporate income taxes.

For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long a Fund or a Portfolio owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that a Fund or a Portfolio owned (or is deemed to have owned) for more than one year that are properly reported by the Fund, or the Portfolio and the applicable Fund, as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that a Fund or a Portfolio owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income when distributed to you by the Fund. Distributions of investment income properly reported by a Fund, or by a Portfolio and the applicable Fund, as derived from “qualified dividend income,” which will not include income from the Fund's or the Portfolio's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by the shareholder, the Fund, and the, if applicable, the Portfolio. Distributions are taxable to you even if they are paid from income or gains earned by a Fund or a Portfolio before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares.Distributions in excess of a Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Fund's shares, and, in general, as capital gain thereafter.

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Any gain resulting from the redemption or other taxable disposition of Fund Shares generally will also be taxable to you as either short-term or long-term capital gain, depending upon how long you held such Fund Shares.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund, including any capital gain dividends, and net gains recognized on the redemption of Fund Shares.

A Fund's or a Portfolio's income from or the proceeds of dispositions of its investments in non-U.S. assets may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. In certain instances, a Fund or a Portfolio and, in turn, a Fund may be entitled to elect to pass through to its shareholders a credit (or deduction, for a shareholder that itemizes deductions and so chooses) for foreign taxes (if any) borne with respect to foreign securities income earned by the Fund or the Portfolio. If the Fund or, as applicable, the Portfolio and the Fund so elect, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the Fund or the Portfolio. There can be no assurance that a Portfolio and/or a Fund will make such election, even if each is eligible to do so. If a Portfolio or a Fund does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes paid by the Fund or the Portfolio; in that case the foreign tax will nonetheless reduce the Fund's and/or the Portfolio's taxable income. Even if a Portfolio and a Fund elect to pass through to shareholders foreign tax credits or deductions, tax-exempt shareholders and those who invest in the Fund through tax-advantaged accounts such as IRAs will not benefit from any such tax credit or deduction. Under certain circumstances, if a Portfolio or a Fund receives a refund of foreign taxes paid in respect of a prior year, the value of Fund Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Portfolio's or the Fund's foreign taxes for the current year could be reduced.

Certain of a Fund's or a Portfolio's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of a Fund's distributions, or a Portfolio's distributions to a Fund, and, in turn, a Fund's distributions to shareholders, and may require the Fund or the Portfolio to sell its investments at a time when it is not advantageous to do so.

A Fund's investments in a Portfolio may cause the tax treatment of the Fund's gains, losses and distributions to differ from the tax treatment that would apply if the Fund invested directly in the types of securities held by the Portfolio. As a result, investors may receive taxable distributions earlier and recognize higher amounts of capital gain or ordinary income than they otherwise would.

If you are not a U.S. person, dividends paid by a Fund that the Fund properly reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends, each as further defined in the SAI, are not subject to withholding of U.S. federal income tax, provided that certain requirements are met. A Fund is permitted, but is not required, to report any part of its dividends as are eligible for such treatment. A Fund's dividends other than those the Fund so reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends generally will be subject to U.S. withholding tax at a 30% rate (or lower applicable treaty rate). See each Fund's SAI for further information.

The U.S. Treasury and the Internal Revenue Service (the “IRS”) generally require a Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Code, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the IRS for redemptions of Fund Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Funds and not through a Financial Intermediary, DST Asset Manager Solutions, Inc. will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

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Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Funds have adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which a Fund may compensate SSGA FD (or others) for services in connection with the distribution of a Fund's Class A shares and for services provided to shareholders in that class (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.25% of each Fund's net assets attributable to its Class A shares. Because these fees are paid out of the assets of a Fund attributable to its Class A shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

A Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of that Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

In addition to payments under the Plan described above, the Funds may reimburse SSGA FD or its affiliates for payments made to Financial Intermediaries that provide certain administrative, recordkeeping, and account maintenance services. The amount of the reimbursement and the manner in which it is calculated are reviewed by the Trustees periodically.

Financial Intermediaries are firms that sell shares of mutual funds, including the Funds, and/or provide certain administrative and account maintenance services to mutual fund investors. Financial Intermediaries may include, among others, brokers, financial planners or advisers, banks, retirement plan recordkeepers and insurance companies.

In some cases, a Financial Intermediary may hold its clients' Fund Shares in nominee or street name and may utilize omnibus accounts. Shareholder services provided by a Financial Intermediary may (though they will not necessarily) include, among other things: establishing and maintaining shareholder account registrations; receiving and processing purchase and redemption orders, including aggregated orders and delivering orders to the Fund's transfer agent; processing and mailing trade confirmations, periodic statements, prospectuses, annual reports, semiannual reports, shareholder notices, and other SEC-required communications; capturing and processing tax data; issuing and mailing dividend checks to shareholders who have selected cash distributions; preparing record date shareholder lists for proxy solicitations; and collecting and posting distributions to shareholder accounts.

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Funds. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Funds or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Funds or its affiliates with respect to the different share classes offered by the Funds.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Funds' shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Funds' shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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If payments to Financial Intermediaries by the distributor or adviser for a particular mutual fund complex exceed payments by other mutual fund complexes, your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend that fund complex over others. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by SSGA FD and its affiliates and by sponsors of other mutual funds he or she may recommend to you. You should also consult disclosures made by your Financial Intermediary at the time of purchase.

Third-Party Transactions. The State Street Funds have authorized certain Financial Intermediaries to accept purchase, redemption and exchange orders on the State Street Funds' behalf. Orders received for a State Street Fund by a Financial Intermediary that has been authorized to accept orders on the Fund's behalf (or other Financial Intermediaries designated by the Financial Intermediary) will be deemed accepted by the Fund at the time they are received by the Financial Intermediary and will be priced based on the Fund's next NAV determination as long as the Financial Intermediary transmits the order in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will be the sole party to determine if a trade is received in good order. The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to a Fund.

If you are purchasing, selling, exchanging or holding State Street Fund shares through a program of services offered by a Financial Intermediary, you may be required by the Financial Intermediary to pay additional fees. You should contact the Financial Intermediary for information concerning what additional fees, if any, may be charged.

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Financial Highlights

The financial highlight tables are intended to help you understand each Fund's financial performance since each Fund's inception. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in each Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with each Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of each Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET AGGREGATE BOND INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class A
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$105.53	$101.10	$95.50	$98.20	$97.50
Income (loss) from investment operations:
Net investment income (loss) (b)	1.45	2.18	3.40	2.60	2.10
Net realized and unrealized gain (loss)	(3.79)	5.10	4.40	(3.00)	0.80
Total from investment operations	(2.34)	7.28	7.80	(0.40)	2.90
Distributions to shareholders from:
Net investment income	(1.44)	(2.06)	(2.20)	(2.30)	(2.10)
Net realized gains	(1.43)	(0.79)	—	—	(0.10)
Total distributions	(2.87)	(2.85)	(2.20)	(2.30)	(2.20)
Net asset value, end of period	$100.32	$105.53	$101.10	$95.50	$98.20
Total return (c)	(2.22)%	7.25%	8.27%	(0.39)%	2.93%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$10,742	$11,200	$19,325	$1,121	$340
Ratios to Average Net Assets:
Total expenses (d)	0.58%	0.66%	0.68%	0.55%	0.58%
Net expenses (d)	0.47%	0.48%	0.48%	0.31%	0.40%
Net investment income (loss)	1.41%	2.08%	3.45%	2.74%	2.11%
Portfolio turnover rate (e)	29%	37%	69%	90%	99%

(a)	After the close of trading on April 17, 2020, the State Street Aggregate Bond Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET AGGREGATE BOND INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$105.23	$100.80	$95.50	$98.40	$97.60
Income (loss) from investment operations:
Net investment income (loss) (b)	1.69	2.38	2.70	2.70	2.30
Net realized and unrealized gain (loss)	(3.77)	5.20	5.40	(2.90)	0.90
Total from investment operations	(2.08)	7.58	8.10	(0.20)	3.20
Distributions to shareholders from:
Net investment income	(1.69)	(2.36)	(2.80)	(2.70)	(2.30)
Net realized gains	(1.43)	(0.79)	—	—	(0.10)
Total distributions	(3.12)	(3.15)	(2.80)	(2.70)	(2.40)
Net asset value, end of period	$100.03	$105.23	$100.80	$95.50	$98.40
Total return (c)	(1.97)%	7.57%	8.55%	(0.20)%	3.29%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$7,160	$8,073	$7,273	$10,598	$10,807
Ratios to Average Net Assets:
Total expenses (d)	0.33%	0.41%	0.32%	0.27%	0.26%
Net expenses (d)	0.22%	0.23%	0.12%	0.04%	0.08%
Net investment income (loss)	1.65%	2.27%	2.73%	2.78%	2.30%
Portfolio turnover rate (e)	29%	37%	69%	90%	99%

(a)	After the close of trading on April 17, 2020, the State Street Aggregate Bond Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET AGGREGATE BOND INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$105.20	$100.80	$95.50	$98.30	$97.50
Income (loss) from investment operations:
Net investment income (loss) (b)	1.92	2.59	2.90	2.70	2.30
Net realized and unrealized gain (loss)	(3.79)	5.20	5.20	(2.80)	0.90
Total from investment operations	(1.87)	7.79	8.10	(0.10)	3.20
Distributions to shareholders from:
Net investment income	(1.89)	(2.60)	(2.80)	(2.70)	(2.30)
Net realized gains	(1.43)	(0.79)	—	—	(0.10)
Total distributions	(3.32)	(3.39)	(2.80)	(2.70)	(2.40)
Net asset value, end of period	$100.01	$105.20	$100.80	$95.50	$98.30
Total return (c)	(1.77)%	7.79%	8.57%	(0.10)%	3.30%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$621,039	$362,294	$210,489	$127,817	$97,318
Ratios to Average Net Assets:
Total expenses (d)	0.13%	0.21%	0.23%	0.27%	0.26%
Net expenses (d)	0.02%	0.03%	0.03%	0.04%	0.08%
Net investment income (loss)	1.88%	2.47%	2.94%	2.83%	2.37%
Portfolio turnover rate (e)	29%	37%	69%	90%	99%

(a)	After the close of trading on April 17, 2020, the State Street Aggregate Bond Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class A Shares
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$286.88	$247.00	$196.40	$216.30	$188.30
Income (loss) from investment operations:
Net investment income (loss) (b)	3.49	3.20	4.20	6.40	1.60
Net realized and unrealized gain (loss)	76.69	40.72	56.30	(16.60)	38.20
Total from investment operations	80.18	43.92	60.50	(10.20)	39.80
Distributions to shareholders from:
Net investment income	(3.29)	(3.24)	(3.70)	(3.70)	(3.90)
Net realized gains	(4.95)	(0.80)	(6.20)	(6.00)	(7.90)
Total distributions	(8.24)	(4.04)	(9.90)	(9.70)	(11.80)
Net asset value, end of period	$358.82	$286.88	$247.00	$196.40	$216.30
Total return (c)	27.94%	17.79%	30.78%	(4.72)%	21.12%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$95,176	$67,324	$55,604	$31,766	$6,293
Ratios to Average Net Assets:
Total expenses (d)	0.55%	0.56%	0.57%	0.38%	0.56%
Net expenses (d)	0.47%	0.47%	0.47%	0.28%	0.48%
Net investment income (loss)	1.07%	1.29%	1.81%	2.89%	0.79%
Portfolio turnover rate (e)	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index Fund underwent a 1-for-10 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the State Street Equity 500 Index II Portfolio.
(e)	Portfolio turnover rate is from the State Street Equity 500 Index II Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I Shares
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$286.96	$247.10	$196.50	$216.30	$188.40
Income (loss) from investment operations:
Net investment income (loss) (b)	4.85	4.39	3.20	4.40	8.90
Net realized and unrealized gain (loss)	76.26	40.24	58.10	(14.10)	31.40
Total from investment operations	81.11	44.63	61.30	(9.70)	40.30
Distributions to shareholders from:
Net investment income	(4.21)	(3.97)	(4.50)	(4.10)	(4.50)
Net realized gains	(4.95)	(0.80)	(6.20)	(6.00)	(7.90)
Total distributions	(9.16)	(4.77)	(10.70)	(10.10)	(12.40)
Net asset value, end of period	$358.91	$286.96	$247.10	$196.50	$216.30
Total return (c)	28.25%	18.07%	31.17%	(4.45)%	21.35%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$38,162	$21,365	$14,478	$14,496	$16,084
Ratios to Average Net Assets:
Total expenses (d)	0.30%	0.31%	0.24%	0.15%	0.31%
Net expenses (d)	0.22%	0.22%	0.15%	0.05%	0.23%
Net investment income (loss)	1.47%	1.75%	1.38%	1.98%	4.21%
Portfolio turnover rate (e)	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index Fund underwent a 1-for-10 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the State Street Equity 500 Index II Portfolio.
(e)	Portfolio turnover rate is from the State Street Equity 500 Index II Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K Shares
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$286.97	$247.10	$196.40	$216.20	$188.30
Income (loss) from investment operations:
Net investment income (loss) (b)	5.43	5.92	5.10	4.70	4.40
Net realized and unrealized gain (loss)	76.42	39.30	56.60	(14.30)	36.40
Total from investment operations	81.85	45.22	61.70	(9.60)	40.80
Distributions to shareholders from:
Net investment income	(4.95)	(4.55)	(4.80)	(4.20)	(5.00)
Net realized gains	(4.95)	(0.80)	(6.20)	(6.00)	(7.90)
Total distributions	(9.90)	(5.35)	(11.00)	(10.20)	(12.90)
Net asset value, end of period	$358.92	$286.97	$247.10	$196.40	$216.20
Total return (c)	28.51%	18.32%	31.39%	(4.42)%	21.61%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,950,849	$1,779,491	$827,654	$485,040	$412,903
Ratios to Average Net Assets:
Total expenses (d)	0.10%	0.11%	0.12%	0.12%	0.11%
Net expenses (d)	0.02%	0.02%	0.02%	0.02%	0.03%
Net investment income (loss)	1.65%	2.37%	2.22%	2.08%	2.14%
Portfolio turnover rate (e)	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index Fund underwent a 1-for-10 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the State Street Equity 500 Index II Portfolio.
(e)	Portfolio turnover rate is from the State Street Equity 500 Index II Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET GLOBAL ALL CAP EQUITY EX- U.S. INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class A
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$107.01	$98.00	$84.60	$106.70	$87.40
Income (loss) from investment operations:
Net investment income (loss) (b)	2.53	1.63	3.20	3.60	0.80
Net realized and unrealized gain (loss)	5.89	8.74	14.50	(19.00)	22.50
Total from investment operations	8.42	10.37	17.70	(15.40)	23.30
Distributions to shareholders from:
Net investment income	(2.40)	(1.34)	(2.50)	(2.30)	(2.60)
Net realized gains	(1.77)	(0.02)	(1.80)	(4.40)	(1.40)
Total distributions	(4.17)	(1.36)	(4.30)	(6.70)	(4.00)
Net asset value, end of period	$111.26	$107.01	$98.00	$84.60	$106.70
Total return (c)	7.88%	10.47%	21.01%	(14.38)%	26.68%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$12,507	$9,413	$7,104	$3,599	$927
Ratios to Average Net Assets:
Total expenses (d)	0.63%	0.70%	0.71%	0.57%	0.53%
Net expenses (d)	0.46%	0.46%	0.45%	0.42%	0.44%
Net investment income (loss)	2.21%	1.79%	3.44%	3.59%	0.79%
Portfolio turnover rate (e)	2%	2%	28%	4%	2%

(a)	After the close of trading on April 17, 2020, the State Street Global All Cap Equity ex-U.S. Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET GLOBAL ALL CAP EQUITY EX- U.S. INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$107.12	$98.10	$84.60	$106.70	$87.40
Income (loss) from investment operations:
Net investment income (loss) (b)	2.87	1.26	2.70	2.30	2.10
Net realized and unrealized gain (loss)	5.91	9.44	15.40	(17.60)	21.40
Total from investment operations	8.78	10.70	18.10	(15.30)	23.50
Distributions to shareholders from:
Net investment income	(2.76)	(1.66)	(2.80)	(2.40)	(2.80)
Net realized gains	(1.77)	(0.02)	(1.80)	(4.40)	(1.40)
Total distributions	(4.53)	(1.68)	(4.60)	(6.80)	(4.20)
Net asset value, end of period	$111.37	$107.12	$98.10	$84.60	$106.70
Total return (c)	8.21%	10.91%	21.24%	(14.18)%	27.00%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$676	$419	$739	$635	$999
Ratios to Average Net Assets:
Total expenses (d)	0.32%	0.40%	0.38%	0.43%	0.23%
Net expenses (d)	0.16%	0.16%	0.12%	0.30%	0.15%
Net investment income (loss)	2.50%	1.37%	2.90%	2.27%	2.12%
Portfolio turnover rate (e)	2%	2%	28%	4%	2%

(a)	After the close of trading on April 17, 2020, the State Street Global All Cap Equity ex-U.S. Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET GLOBAL ALL CAP EQUITY EX- U.S. INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$107.24	$98.20	$84.70	$106.80	$87.40
Income (loss) from investment operations:
Net investment income (loss) (b)	3.41	2.49	2.90	2.60	3.20
Net realized and unrealized gain (loss)	5.54	8.40	15.40	(17.70)	20.40
Total from investment operations	8.95	10.89	18.30	(15.10)	23.60
Distributions to shareholders from:
Net investment income	(2.92)	(1.83)	(3.00)	(2.60)	(2.80)
Net realized gains	(1.77)	(0.02)	(1.80)	(4.40)	(1.40)
Total distributions	(4.69)	(1.85)	(4.80)	(7.00)	(4.20)
Net asset value, end of period	$111.50	$107.24	$98.20	$84.70	$106.80
Total return (c)	8.36%	11.08%	21.49%	(14.03)%	27.11%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,136,787	$795,026	$423,417	$433,086	$456,567
Ratios to Average Net Assets:
Total expenses (d)	0.18%	0.25%	0.27%	0.18%	0.18%
Net expenses (d)	0.01%	0.01%	0.01%	0.05%	0.10%
Net investment income (loss)	2.97%	2.70%	3.12%	2.57%	3.16%
Portfolio turnover rate (e)	2%	2%	28%	4%	2%

(a)	After the close of trading on April 17, 2020, the State Street Global All Cap Equity ex-U.S. Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET SMALL/MID CAP EQUITY INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class A
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$330.61	$253.40	$209.40	$239.00	$213.40
Income (loss) from investment operations:
Net investment income (loss) (b)	10.39	2.82	4.40	6.40	10.60
Net realized and unrealized gain (loss)	29.12	77.73	53.00	(29.00)	27.40
Total from investment operations	39.51	80.55	57.40	(22.60)	38.00
Distributions to shareholders from:
Net investment income	(10.62)	(0.71)	(4.60)	(3.00)	(5.00)
Net realized gains	(20.56)	(2.63)	(8.80)	(4.00)	(7.40)
Total distributions	(31.18)	(3.34)	(13.40)	(7.00)	(12.40)
Net asset value, end of period	$338.94	$330.61	$253.40	$209.40	$239.00
Total return (c)	11.95%	31.79%	27.42%	(9.35)%	17.87%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$44,290	$25,877	$22,037	$9,274	$988
Ratios to Average Net Assets:
Total expenses (d)	0.60%	0.69%	0.79%	0.80%	1.10%
Net expenses (d)	0.49%	0.50%	0.49%	0.29%	0.35%
Net investment income (loss)	2.82%	1.12%	1.76%	2.65%	4.60%
Portfolio turnover rate (e)	28%	52%	51%	22%	21%

(a)	After the close of trading on April 17, 2020, the State Street Small/Mid Cap Equity Index Fund underwent a 1-for-20 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET SMALL/MID CAP EQUITY INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$330.66	$253.40	$209.60	$239.00	$213.40
Income (loss) from investment operations:
Net investment income (loss) (b)	9.73	3.20	3.80	4.00	8.00
Net realized and unrealized gain (loss)	30.71	78.24	54.40	(25.80)	30.60
Total from investment operations	40.44	81.44	58.20	(21.80)	38.60
Distributions to shareholders from:
Net investment income	(11.55)	(1.55)	(5.60)	(3.60)	(5.60)
Net realized gains	(20.56)	(2.63)	(8.80)	(4.00)	(7.40)
Total distributions	(32.11)	(4.18)	(14.40)	(7.60)	(13.00)
Net asset value, end of period	$338.99	$330.66	$253.40	$209.60	$239.00
Total return (c)	12.22%	32.15%	27.70%	(9.07)%	18.16%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$11,663	$7,400	$6,312	$5,038	$4,135
Ratios to Average Net Assets:
Total expenses (d)	0.35%	0.44%	0.46%	0.61%	0.90%
Net expenses (d)	0.24%	0.25%	0.17%	0.07%	0.11%
Net investment income (loss)	2.65%	1.28%	1.58%	1.58%	3.42%
Portfolio turnover rate (e)	28%	52%	51%	22%	21%

(a)	After the close of trading on April 17, 2020, the State Street Small/Mid Cap Equity Index Fund underwent a 1-for-20 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET SMALL/MID CAP EQUITY INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$330.71	$253.40	$209.60	$239.00	$213.40
Income (loss) from investment operations:
Net investment income (loss) (b)	12.44	7.44	5.40	5.80	3.00
Net realized and unrealized gain (loss)	28.74	74.73	53.00	(27.60)	35.60
Total from investment operations	41.18	82.17	58.40	(21.80)	38.60
Distributions to shareholders from:
Net investment income	(12.30)	(2.23)	(5.80)	(3.60)	(5.60)
Net realized gains	(20.56)	(2.63)	(8.80)	(4.00)	(7.40)
Total distributions	(32.86)	(4.86)	(14.60)	(7.60)	(13.00)
Net asset value, end of period	$339.03	$330.71	$253.40	$209.60	$239.00
Total return (c)	12.45%	32.44%	27.84%	(9.03)%	18.16%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$354,408	$216,700	$77,885	$38,195	$18,750
Ratios to Average Net Assets:
Total expenses (d)	0.15%	0.24%	0.34%	0.55%	0.96%
Net expenses (d)	0.04%	0.05%	0.05%	0.04%	0.05%
Net investment income (loss)	3.38%	2.91%	2.17%	2.37%	1.29%
Portfolio turnover rate (e)	28%	52%	51%	22%	21%

(a)	After the close of trading on April 17, 2020, the State Street Small/Mid Cap Equity Index Fund underwent a 1-for-20 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the corresponding Portfolio.
(e)	Portfolio turnover rate is from the corresponding Portfolio.

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Index/Trademark Licenses/Disclaimers

The Index Providers are not affiliated with the Trust, the Adviser, the Funds' Administrator, Sub-Administrator, Custodian, Transfer Agent, SSGA FD or any of their respective affiliates. The Adviser (“Licensee”) has entered into license agreements with the Index Providers pursuant to which the Adviser pays a fee to use their respective Indices. The Adviser is sub-licensing rights to the Indices to the Funds at no charge.

S&P Index: The S&P 500^® Index (the “Index”) is a product of S&P Dow Jones Indices LLC or its affiliates (“SPDJI”) and has been licensed for use by the Adviser. S&P^®, Standard & Poor's^®, and S&P 500^® are registered trademarks of Standard & Poor's Financial Services LLC (“S&P”); Dow Jones^® is a registered trademark of Dow Jones Trademark Holdings LLC (“Dow Jones”); and these trademarks have been licensed for use by SPDJI and sub-licensed for certain purposes by the Adviser. It is not possible to invest in an index.

The State Street Equity 500 Index Fund is not sponsored, endorsed, sold or marketed by SPDJI, Dow Jones, S&P, any of their respective affiliates (collectively, “S&P Dow Jones Indices”). S&P Dow Jones Indices does not make any representation or warranty, express or implied, to the owners of the State Street Equity 500 Index Fund or any member of the public regarding the advisability of investing in securities generally or in the State Street Equity 500 Index Fund particularly or the ability of the Index to track general market performance. S&P Dow Jones Indices licenses to Licensee the Index and certain trademarks, service marks and/or trade names of S&P Dow Jones Indices and/or its licensors. The Index is determined, composed and calculated by S&P Dow Jones Indices without regard to Licensee or the State Street Equity 500 Index Fund. S& P Dow Jones Indices has no obligation to take the needs of Licensee or the owners of the State Street Equity 500 Index Fund into consideration in determining, composing or calculating the Index. S&P Dow Jones Indices is not responsible for and has not participated in the determination of the prices, and amount of the State Street Equity 500 Index Fund or the timing of the issuance or sale of the State Street Equity 500 Index Fund or in the determination or calculation of the equation by which the State Street Equity 500 Index Fund is to be converted into cash, surrendered or redeemed, as the case may be. S&P Dow Jones Indices has no obligation or liability in connection with the administration, marketing or trading of the State Street Equity 500 Index Fund. S&P Dow Jones Indices LLC is not an investment or tax advisor. Inclusion of a security within an index is not a recommendation by S&P Dow Jones Indices to buy, sell, or hold such security, nor is it considered to be investment advice.

NEITHER S&P DOW JONES INDICES NOR THIRD PARTY LICENSOR GUARANTEES THE ADEQUACY, ACCURACY, TIMELINESS AND/OR THE COMPLETENESS OF THE INDEX OR ANY DATA RELATED THERETO OR ANY COMMUNICATION, INCLUDING BUT NOT LIMITED TO, ORAL OR WRITTEN COMMUNICATION (INCLUDING ELECTRONIC COMMUNICATIONS) WITH RESPECT THERETO. S&P DOW JONES INDICES AND THIRD PARTY LICENSOR SHALL NOT BE SUBJECT TO ANY DAMAGES OR LIABILITY FOR ANY ERRORS, OMISSIONS, OR DELAYS THEREIN. S&P DOW JONES INDICES AND THIRD PARTY LICENSOR MAKES NO EXPRESS OR IMPLIED WARRANTIES, AND EXPRESSLY DISCLAIMS ALL WARRANTIES, OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE OR AS TO RESULTS TO BE OBTAINED BY LICENSEE, OWNERS OF THE STATE STREET EQUITY 500 INDEX FUND, OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE INDICES OR WITH RESPECT TO ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT WHATSOEVER SHALL S&P DOW JONES INDEX OR THIRD PARTY LICENSOR BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES INCLUDING BUT NOT LIMITED TO, LOSS OF PROFITS, TRADING LOSSES, LOST TIME OR GOODWILL, EVEN IF THEY HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, WHETHER IN CONTRACT, TORT, STRICT LIABILITY, OR OTHERWISE. THERE ARE NO THIRD PARTY BENEFICIARIES OF ANY AGREEMENTS OR ARRANGEMENTS BETWEEN S&P DOW JONES INDICES AND LICENSEE, OTHER THAN THE LICENSORS OF S&P DOW JONES INDICES.

“ Bloomberg^®” and the Bloomberg U.S. Aggregate Bond Index (the “Bloomberg Index”) is a service mark of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (“BISL”), the administrator of the Bloomberg Index (collectively, “Bloomberg”), and have been licensed for use for certain purposes by the Licensee.The State Street Aggregate Bond Index Portfolio (the “Product”) is not sponsored, endorsed, sold or marketed by Bloomberg. Bloomberg does not make any representation or warranty, express or implied, to the owners of or counterparties to the Products or any member of the public regarding the advisability of investing in securities generally or in the Product particularly. The only relationship of Bloomberg to the Licensee in respect of the Bloomberg Index is the licensing of certain trademarks, trade names and service marks and of the Bloomberg Index, which is determined, composed and calculated by BISL without regard to the Licensee or the Product. Bloomberg has no obligation to take the needs of the Licensee or the owners of the Product into consideration in determining, composing or calculating the Bloomberg Index. Bloomberg is not responsible for and has not participated in the determination of the timing, price, or quantities of the Product to be issued. Bloomberg shall not have any obligation or liability, including, without limitation, to the Product's customers, in

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connection with the administration, marketing or trading of the Product.BLOOMBERG DOES NOT GUARANTEE THE ACCURACY AND/OR THE COMPLETENESS OF THE BLOOMBERG INDEX OR ANY DATA RELATED THERETO AND SHALL HAVE NO LIABILITY FOR ANY ERRORS, OMISSIONS OR INTERRUPTIONS THEREIN. BLOOMBERG DOES NOT MAKE ANY WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY THE LICENSEE, OWNERS OF THE PRODUCTS OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE BLOOMBERG INDEX OR ANY DATA RELATED THERETO. BLOOMBERG DOES NOT MAKE ANY EXPRESS OR IMPLIED WARRANTIES AND EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE BLOOMBERG INDEX OR ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, TO THE MAXIMUM EXTENT ALLOWED BY LAW, BLOOMBERG, ITS LICENSORS, AND ITS AND THEIR RESPECTIVE EMPLOYEES, CONTRACTORS, AGENTS, SUPPLIERS, AND VENDORS SHALL HAVE NO LIABILITY OR RESPONSIBILITY WHATSOEVER FOR ANY INJURY OR DAMAGES—WHETHER DIRECT, INDIRECT, CONSEQUENTIAL, INCIDENTAL, PUNITIVE OR OTHERWISE—ARISING IN CONNECTION WITH THE PRODUCTS OR BLOOMBERG INDEX OR ANY DATA OR VALUES RELATING THERETO—WHETHER ARISING FROM THEIR NEGLIGENCE OR OTHERWISE, EVEN IF NOTIFIED OF THE POSSIBILITY THEREOF.

THE STATE STREET GLOBAL ALL CAP EQUITY EX-U.S. INDEX FUND IS NOT SPONSORED, ENDORSED, SOLD OR PROMOTED BY MSCI INC. (“MSCI”), MSCI'S PARENT COMPANY, ANY OF MSCI'S OR MSCI'S PARENT COMPANY'S DIRECTLY OR INDIRECTLY HELD SUBSIDIARIES, ANY OF MSCI'S OR MSCI'S PARENT COMPANY'S INFORMATION PROVIDERS OR ANY THIRD PARTY INVOLVED IN, OR RELATED TO, COMPILING, COMPUTING OR CREATING ANY MSCI INDEX (COLLECTIVELY, THE “MSCI PARTIES”).THE MSCI INDICES ARE THE EXCLUSIVE PROPERTY OF MSCI. MSCI AND THE MSCI INDEX NAMES ARE SERVICE MARK(S) OF MSCI OR ITS AFFILIATES AND HAVE BEEN LICENSED FOR USE FOR CERTAIN PURPOSES BY THE LICENSEE. NONE OF THE MSCI PARTIES MAKES ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY REGARDING THE ADVISABILITY OF INVESTING IN FUNDS GENERALLY OR IN THE MSCI FUNDS PARTICULARLY OR THE ABILITY OF ANY MSCI INDEX TO TRACK CORRESPONDING STOCK MARKET PERFORMANCE. MSCI OR ITS AFFILIATES ARE THE LICENSORS OF CERTAIN TRADEMARKS, SERVICE MARKS AND TRADE NAMES AND OF THE MSCI INDICES WHICH ARE DETERMINED, COMPOSED AND CALCULATED BY MSCI WITHOUT REGARD TO THE MSCI FUNDS OR THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY. NONE OF THE MSCI PARTIES HAS ANY OBLIGATION TO TAKE THE NEEDS OF THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY INTO CONSIDERATION IN DETERMINING, COMPOSING OR CALCULATING THE MSCI INDICES. NONE OF THE MSCI PARTIES IS RESPONSIBLE FOR OR HAS PARTICIPATED IN THE DETERMINATION OF THE TIMING OF, PRICES AT, OR QUANTITIES OF THE MSCI FUNDS TO BE ISSUED OR IN THE DETERMINATION OR CALCULATION OF THE EQUATION BY OR THE CONSIDERATION INTO WHICH THE MSCI FUNDS ARE REDEEMABLE. FURTHER, NONE OF THE MSCI PARTIES HAS ANY OBLIGATION OR LIABILITY TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY IN CONNECTION WITH THE ADMINISTRATION, MARKETING OR OFFERING OF THE MSCI FUNDS.

ALTHOUGH MSCI SHALL OBTAIN INFORMATION FOR INCLUSION IN OR FOR USE IN THE CALCULATION OF THE MSCI INDICES FROM SOURCES THAT MSCI CONSIDERS RELIABLE, NONE OF THE MSCI PARTIES WARRANTS OR GUARANTEES THE ORIGINALITY, ACCURACY AND/OR THE COMPLETENESS OF ANY MSCI INDEX OR ANY DATA INCLUDED THEREIN. NONE OF THE MSCI PARTIES MAKES ANY WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY THE ISSUER OF THE MSCI FUNDS, OWNERS OF THE FUNDS, OR ANY OTHER PERSON OR ENTITY, FROM THE USE OF ANY MSCI INDEX OR ANY DATA INCLUDED THEREIN. NONE OF THE MSCI PARTIES SHALL HAVE ANY LIABILITY FOR ANY ERRORS, OMISSIONS OR INTERRUPTIONS OF OR IN CONNECTION WITH ANY MSCI INDEX OR ANY DATA INCLUDED THEREIN. FURTHER, NONE OF THE MSCI PARTIES MAKES ANY EXPRESS OR IMPLIED WARRANTIES OF ANY KIND, AND THE MSCI PARTIES HEREBY EXPRESSLY DISCLAIM ALL WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO EACH MSCI INDEX AND ANY DATA INCLUDED THEREIN. WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT SHALL ANY OF THE MSCI PARTIES HAVE ANY LIABILITY FOR ANY DIRECT, INDIRECT, SPECIAL, PUNITIVE, CONSEQUENTIAL OR ANY OTHER DAMAGES (INCLUDING LOST PROFITS) EVEN IF NOTIFIED OF THE POSSIBILITY OF SUCH DAMAGES.

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NO PURCHASER, SELLER OR HOLDER OF THE MSCI FUNDS, OR ANY OTHER PERSON OR ENTITY, SHOULD USE OR REFER TO ANY MSCI TRADE NAME, TRADEMARK OR SERVICE MARK TO SPONSOR, ENDORSE, MARKET OR PROMOTE THESE FUNDS WITHOUT FIRST CONTACTING MSCI TO DETERMINE WHETHER MSCI'S PERMISSION IS REQUIRED. UNDER NO CIRCUMSTANCES MAY ANY PERSON OR ENTITY CLAIM ANY AFFILIATION WITH MSCI WITHOUT THE PRIOR WRITTEN PERMISSION OF MSCI.

The State Street Small/Mid Cap Equity Index Fund has been developed solely by the Adviser. The State Street Small/Mid Cap Equity Index Fund is not in any way connected to or sponsored, endorsed, sold or promoted by the London Stock Exchange Group plc and its group undertakings (collectively, the “LSE Group”). FTSE Russell is a trading name of certain of the LSE Group companies.

All rights in the Russell Small Cap Completeness Index (the “Index”) vest in the relevant LSE Group company which owns the Index. “Russell^®” is a trademark of the relevant LSE Group company and is used by any other LSE Group company under license.

The Index is calculated by or on behalf of FTSE International Limited or its affiliate, agent or partner. The LSE Group does not accept any liability whatsoever to any person arising out of (a) the use of, reliance on or any error in the Index or (b) investment in or operation of the State Street Small/Mid Cap Equity Index Fund. The LSE Group makes no claim, prediction, warranty or representation either as to the results to be obtained from the State Street Small/Mid Cap Equity Index Fund or the suitability of the Index for the purpose to which it is being put by the Adviser.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

The Funds do not consider the U.S. Postal Service or other independent delivery services to be their agents. Therefore, deposits in the mail or with such services, or receipt at the Funds' post office box, of purchase orders or redemption requests, do not constitute receipt by the Funds or Transfer Agent.

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. In a Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (800) 997-7327 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com.

Reports and other information about the Funds are available free of charge on the EDGAR Database on the SEC's Internet site at http://www.sec.gov. Copies of this information also may be obtained, after paying a duplicating fee, by electronic request at the following E-mail address: publicinfo@sec.gov.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITEQABSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Emerging Markets Equity Index Fund

Class A (SSUEX) Class I (SSLEX) Class K (SSKEX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the Fund offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund may offer multiple classes of shares. This Prospectus covers only the Class A, Class I and Class K Shares of the Fund.

TABLE OF CONTENTS

Fund Summary	1
State Street Emerging Markets Equity Index Fund	1
Additional Information About Investment Objectives, Principal Strategies and Risks	10
Additional Information About Non-Principal Investment Strategies and Risks	21
Portfolio Holdings Disclosure	22
Management and Organization	23
Shareholder Information	25
Dividends, Distributions and Tax Considerations	38
Financial Intermediary Arrangements	39
Financial Highlights	42

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State Street Emerging Markets Equity Index Fund

Investment Objective

The State Street Emerging Markets Equity Index Fund (the “Emerging Markets Equity Index Fund” or the “Fund”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return of an index that tracks the performance of emerging market equity securities.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 27 of the Fund's Prospectus.

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee	0.14%	0.14%	0.14%
Distribution and/or Shareholder Service (12b-1) Fees	0.25%	0.00%	0.00%
Other Expenses²	0.36%	0.36%	0.16%
Total Annual Fund Operating Expenses	0.75%	0.50%	0.30%
Less Fee Waivers and/or Expense Reimbursements³	(0.13%)	(0.13%)	(0.13%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.62%	0.37%	0.17%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.
²	Other Expenses are based on estimates for the current fiscal year for Class A and Class I shares.

Example:

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	1 year	3 years	5 years	10 years
Class A	$585	$740	$908	$1,395
Class I	$38	$147	$267	$616
Class K	$17	$83	$156	$368

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 11% of the average value of its portfolio.

Principal Investment Strategies

The Fund is an “index” fund that seeks to track, before fees and expenses, the total return of the MSCI Emerging Markets Index (the “Index”) over the long term. As an “index” fund, the Fund is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment.

In seeking to track the performance of the Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to create a portfolio of securities with generally the same risk and return characteristics as those of the Index. The number of holdings in the Fund will be based on a number of factors, including asset size of the Fund. SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index, in approximately the same proportions as the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Fund's investment objective. In addition, from time to time stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal circumstances, the Fund generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities included in the Index or in other securities of emerging market companies providing exposure comparable, in the Adviser's view, to securities comprising the Index. An “emerging market company” is any company domiciled or doing a substantial portion of its business in countries represented in the Index at the time of purchase. These securities may be represented by American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”), Non-Voting Depositary Receipts (“NVDRs”) or Participatory Notes (“P-Notes”). The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least 60 days' notice prior to any change in this 80% investment policy. The Fund may invest a portion of its assets in cash and cash equivalents, repurchase agreements and money market instruments, such as money market funds (including money market funds advised by the Adviser).

The Fund may purchase or sell futures contracts, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Fund might do so, for example, in order to increase its investment exposure pending investment of cash in stocks or other investments. Alternatively, the Fund might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Fund may enter into other derivatives transactions, including the use of options, forwards or swap transactions, in lieu of investing directly in the stocks making up the Index. The Fund may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Fund (including funds advised by the Adviser).

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sented in the Index have historically included, among others, Brazil, Chile, China, Colombia, Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Korea, Kuwait, Malaysia, Mexico, Peru, Philippines, Poland, Qatar, Russia, Saudi Arabia, South Africa, Taiwan, Thailand, Turkey and United Arab Emirates. As of February 28, 2022, a significant portion of the Index comprised companies in the financial and information technology sectors, although this may change from time to time. As of February 28, 2022, a significant portion of the Index comprised companies located in China, Taiwan and India and a significant portion of the Index constituents are denominated in Hong Kong Dollars and Chinese Yuan, although this may change from time to time.

The Index is sponsored by MSCI, Inc. (the “Index Provider”), which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent that the Fund buys securities denominated in a foreign currency, there are special risks such as changes in currency exchange rates and the risk that a foreign government could regulate foreign exchange transactions. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

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try's dependence on revenue from particular commodities or international aid, less governmental supervision and regulation, unavailability of currency hedging techniques, differences in auditing and financial reporting standards, less stringent investor protection and disclosure standards, less developed public health systems, and less developed legal systems. There is also the potential for unfavorable action such as expropriation, nationalization, embargo, and acts of war. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. These risks are generally greater for investments in frontier market countries, which typically have smaller economies or less developed capital markets than traditional emerging market countries.

China: The Chinese economy is generally considered an emerging market and can be significantly affected by economic and political conditions and policy in China and surrounding Asian countries. A relatively small number of Chinese companies represent a large portion of China's total market and thus may be more sensitive to adverse political or economic circumstances and market movements. The economy of China differs, often unfavorably, from the U.S. economy in such respects as structure, general development, government involvement, wealth distribution, rate of inflation, growth rate, allocation of resources and capital reinvestment, among others. Under China's political and economic system, the central government has historically exercised substantial control over virtually every sector of the Chinese economy through administrative regulation and/or state ownership. The Chinese government may intervene or seek to control the operations, structure, or ownership of Chinese companies, including with respect to foreign investors of such companies. In addition, expropriation, including nationalization, confiscatory taxation, political, economic or social instability or other developments could adversely affect and significantly diminish the values of the Chinese companies in which the Fund invests. The Chinese economy and financial markets have experienced high levels of growth in recent years; any actual or perceived reduction or curtailment in those levels of growth in the future would likely have a substantial adverse impact on the values of Chinese companies. These factors and others could negatively affect the value and liquidity of the Fund. The Fund may invest in shares of Chinese companies traded on stock markets in Mainland China or Hong Kong. These stock markets have recently experienced high levels of volatility, which may continue in the future. The Hong Kong stock market may behave differently from the Mainland China stock market and there may be little to no correlation between the performance of the Hong Kong stock market and the Mainland China stock market. The Fund may gain investment exposure to Chinese companies through variable interest entity (“VIE”) structures. The VIE structure enables foreign investors, such as the Fund, to obtain investment exposure to a Chinese company in situations in which the Chinese government has limited or prohibited non-Chinese ownership of such company. The VIE structure does not involve equity ownership in a China-based company but rather involves claims to the China-based company's profits and control of its assets through contractual arrangements. In addition to the risk of government intervention, investments through a VIE structure are subject to the risk that the China-based company (or its officers, directors, or Chinese equity owners) may breach those contractual arrangements, or Chinese law changes in a way that adversely affects the enforceability of these arrangements, or those contracts are otherwise not enforceable under Chinese law, in which case the Fund may suffer significant losses on its investments through a VIE structure with little or no recourse available. If the Chinese government takes action adversely affecting VIE structures, the market value of the Fund's associated portfolio holdings would likely suffer significant, detrimental, and possibly permanent consequences, which could result in substantial investment losses.

South Korea: Economic and political developments of South Korean neighbors may have an adverse effect on the South Korean economy. Substantial political tensions exist between North Korea and South Korea and, recently, these political tensions have escalated. The outbreak of hostilities between the two nations, or even the threat of such an outbreak, will likely adversely impact the South Korean economy. In addition, South Korea's economic growth potential has recently been on a decline, mainly because of a rapidly aging population and structural problems. Among these structural concerns are the country's underdeveloped financial markets and a general lack of regulatory transparency. The restructuring of the South Korean economy, including the creation of a mechanism

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for bankrupt firms to exit the market, remains an important unfinished task. These factors may adversely affect the South Korean economy and cause a diversion of corporate investment to China and other lower wage countries. South Korea's economic growth potential is susceptible to problems from large scale emigration, rigid labor regulations and ongoing labor relations issues.

Taiwan: Taiwan's geographic proximity and history of political contention with China have resulted in ongoing tensions between the two countries. These tensions may materially affect the Taiwanese economy and its securities market. Taiwan's economy is export-oriented, so it depends on an open world trade regime and remains vulnerable to fluctuations in the world economy. Rising labor costs and increasing environmental consciousness have led some labor-intensive industries to relocate to countries with cheaper work forces, and continued labor outsourcing may adversely affect the Taiwanese economy.

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Financial Institutions Risk: Changes in the creditworthiness of financial institutions (such as banks and broker-dealers) may adversely affect the values of instruments of issuers in financial industries. Adverse developments in banking and other financial industries may cause the Fund to underperform relative to other funds that invest more broadly across different industries or have a smaller exposure to financial institutions. Changes in governmental regulation and oversight of financial institutions may have an adverse effect on the financial condition of a financial institution.

Frontier Markets Risk: Investments in frontier markets may be more volatile and less liquid than investments in more developed markets or in other emerging market countries. Risks that are characteristic of many emerging markets generally may be especially heightened in frontier markets due to political, economic, financial, or other factors.

Futures Contract Risks; Other Exchange-Traded Derivatives: The risk of loss relating to the use of futures contracts and other exchange-traded derivatives is potentially unlimited. There is no assurance that a liquid secondary market on an exchange will exist for any particular futures contract or other exchange-traded derivative or at any particular time. In the event no such market exists for a particular derivative, it might not be possible to effect closing transactions, and the Fund will be unable to terminate its exposure to the derivative. If the Fund uses futures contracts or other exchange-traded derivatives for hedging purposes, there is a risk of imperfect correlation between movements in the prices of the derivatives and movements in the securities or index underlying the derivatives or movements in the prices of the Fund's investments that are the subject of such hedge. Certain foreign futures contracts and other exchange-traded derivatives may be less liquid and more volatile than U.S. contracts. The Fund may be delayed or prevented from recovering margin or other amounts deposited with a futures commission merchant or futures clearinghouse.

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Mid-Capitalization Securities Risk: The securities of mid-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of mid-sized companies may trade less frequently and in smaller volumes than more widely held securities. Some securities of mid-sized issuers may be illiquid or may be restricted as to resale, and their values may be volatile.

Money Market Risk: An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Certain money market funds seek to preserve the value of their shares at $1.00 per share, although there can be no assurance that they will do so, and it is possible to lose money by investing in such a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause the share price of such a money market fund to fall below $1.00. Other money market funds price and transact at a “floating” NAV that will fluctuate along with changes in the market-based value of fund assets. Shares sold utilizing a floating NAV may be worth more or less than their original purchase price. Recent changes in the regulation of money market funds may affect the operations and structures of money market funds.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Class K shares' returns have varied for each full calendar year shown. Except for differences in returns resulting from differences in fees and expenses, all share classes would have substantially similar returns because all share classes invest in the same portfolio of securities. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Return (years ended 12/31)

Highest Quarterly Return: 19.13% (Q4, 2020)
Lowest Quarterly Return: -24.02% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class K				12/18/15
Return Before Taxes	-2.80%	9.67%	9.82%
Return After Taxes on Distributions	-3.17%	9.09%	9.23%
Return After Taxes on Distributions and Sale of Fund Shares	-1.27%	7.65%	7.81%
MSCI Emerging Market Index (reflects no deduction for fees, expenses or taxes other than withholding taxes on reinvested dividends)	-2.54%	9.87%	10.17%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

The professionals primarily responsible for the day-to-day management of the Fund are Michael Feehily, Thomas Coleman and Olga Winner, each of which has served as a portfolio manager of the Fund since inception in 2015.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Thomas Coleman, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. He joined the Adviser in 1998.

Olga Winner, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2007.

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Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The State Street Institutional Investment Trust's (the “Trust”) Board of Trustees (the “Board”) may change the Fund's investment strategies and other policies without shareholder approval, except as otherwise indicated. The Board may change the Fund's investment objective without shareholder approval.

Principal Investment Strategies

In seeking to track the performance of the Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to create a portfolio of securities with generally the same risk and return characteristics as those of the Index. The number of holdings in the Fund will be based on a number of factors, including asset size of the Fund. SSGA FM may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index, in approximately the same proportions as the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Fund's investment objective. In addition, from time to time stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal circumstances, the Fund generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities included in the Index or in other securities of emerging market companies providing exposure comparable, in the Adviser's view, to securities comprising the Index. An “emerging market company” is any company domiciled or doing a substantial portion of its business in countries represented in the Index at the time of purchase. These securities may be represented by American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”), Non-Voting Depositary Receipts (“NVDRs”) or Participatory Notes (“P-Notes”). The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least 60 days' notice prior to any change in this 80% investment policy. The Fund may invest a portion of its assets in cash and cash equivalents, repurchase agreements and money market instruments, such as money market funds (including money market funds advised by the Adviser).

The Index is a free float-adjusted market capitalization index that is designed to measure equity market performance of emerging market countries. As of February 28, 2022, the Index comprised 1,420 securities covering large- and mid-cap companies across 25 countries and represented 87.61% of the market capitalization of MSCI Emerging Markets Investable Market Index (IMI), which is composed of large-, mid- and small-cap companies. As of February 28, 2022, the market capitalization of the companies included in the Index ranged from $65.76 million to $530.72 billion. Countries represented in the Index have historically included, among others, Brazil, Chile, China, Colombia, Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Korea, Kuwait, Malaysia, Mexico, Peru, Philippines, Poland, Qatar, Russia, Saudi Arabia, South Africa, Taiwan, Thailand, Turkey and United Arab Emirates. As of February 28, 2022, a significant portion of the Index comprised companies in the financial and information technology sectors, although this may change from time to time. As of February 28, 2022, a significant portion of the Index comprised companies located in China, Taiwan and India and a significant portion of the Index constituents are denominated in Hong Kong Dollars and Chinese Yuan, although this may change from time to time.

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Additional Index Information. The Index's components are reconstituted and rebalanced semi-annually. The Index Provider classifies each issuer in one country. The Index Provider generally determines the country classification of an issuer based on the issuer's country of incorporation and the primary listing of its securities. To the extent that an issuer is incorporated in a different country than the country in which its securities are principally traded, the Index Provider considers the following additional set of criteria to determine the issuer's country classification: (i) the secondary listings of the issuer's securities, if any; (ii) the geographic distribution of the issuer's shareholder base; (iii) the location of the issuer's headquarters; (iv) the geographic distribution of the issuer's operations (in terms of assets and revenues); (v) the issuer's history with respect to these criteria; and (vi) the country in which investors consider the issuer to be most appropriately classified based on communications between the Index Provider and investors.

Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

Counterparty Risk. The Fund will be subject to credit risk with respect to the counterparties with which the Fund enters into derivatives contracts and other transactions such as repurchase agreements or reverse repurchase agreements. The Fund's ability to profit from these types of investments and transactions will depend on the willingness and ability of its counterparty to perform its obligations. If a counterparty fails to meet its contractual obligations, the Fund may be unable to terminate or realize any gain on the investment or transaction, resulting in a loss to the Fund. The Fund may experience significant delays in obtaining any recovery in an insolvency, bankruptcy, or other reorganization proceeding involving its counterparty (including recovery of any collateral posted by it) and may obtain only a limited recovery or may obtain no recovery in such circumstances. If the Fund holds collateral posted by its counterparty, it may be delayed or prevented from realizing on the collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty. Under applicable law or contractual provisions, including if the Fund enters into an investment or transaction with a financial institution and such financial institution (or an affiliate of the financial institution) experiences financial difficulties, then the Fund may in certain situations be prevented or delayed from exercising its rights to terminate the investment or transaction, or to realize on any collateral and may result in the suspension of payment and delivery obligations of the parties under such investment or transactions or in another institution being substituted for that financial institution without the consent of the Fund. Further, the Fund may be subject to “bail-in” risk under applicable law whereby, if required by the financial institution's authority, the financial institution's liabilities could be written down, eliminated or converted into equity or an alternative instrument of ownership. A bail-in of a financial institution may result in a reduction in value of some or all of its securities and, if the Fund holds such securities or has entered into a transaction with such a financial security when a bail-in occurs, such Fund may also be similarly impacted.

Currency Risk. Investments in issuers in different countries are often denominated in currencies other than the U.S. dollar. Changes in the values of those currencies relative to the U.S. dollar may have a positive or negative effect on the values of the Fund's investments denominated in those currencies. The values of other currencies relative to the U.S. dollar may fluctuate in response to, among other factors, interest rate changes, intervention (or failure to intervene) by national governments, central banks, or supranational entities such as the International Monetary Fund, the imposition of currency controls, and other political or regulatory developments. Currency values can decrease significantly both in the short term and over the long term in response to these and other developments. Continuing uncertainty as to the status of the Euro and the Economic and Monetary Union of the European Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU, or any continued uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of the Fund's portfolio investments.

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may be less liquid and more volatile than the underlying securities in their primary trading market. If a depositary receipt is denominated in a different currency than its underlying securities, the Fund will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. There may be less publicly available information regarding the issuer of the securities underlying a depositary receipt than if those securities were traded directly in U.S. securities markets. Depositary receipts may or may not be sponsored by the issuers of the underlying securities, and information regarding issuers of securities underlying unsponsored depositary receipts may be more limited than for sponsored depositary receipts. The values of depositary receipts may decline for a number of reasons relating to the issuers or sponsors of the depositary receipts, including, but not limited to, insolvency of the issuer or sponsor. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based. To the extent the Fund invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

Derivatives Risk. A derivative is a financial contract the value of which depends on, or is derived from, the value of an underlying asset, interest rate, or index. Derivative transactions typically involve leverage and may have significant volatility. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. Risks associated with derivative instruments include potential changes in value in response to interest rate changes or other market developments or as a result of the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Adviser anticipated or a different or less favorable effect than the Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that the Fund may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that the Fund will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to the Fund due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

Emerging Markets Risk. Investments in emerging markets are generally subject to a greater risk of loss than investments in developed markets. This may be due to, among other things, the possibility of greater market volatility, lower trading volume and liquidity, greater risk of expropriation, nationalization, and social, political and economic instability, greater reliance on a few industries, international trade or revenue from particular commodities, less developed accounting, legal and regulatory systems, higher levels of inflation, deflation or currency devaluation, greater risk of market shut down, and more significant governmental limitations on investment policy as compared to those typically found in a developed market. The Public Company Accounting Oversight Board, which regulates auditors of U.S. public companies, is unable to inspect audit work papers in certain foreign countries. Investors in foreign countries often have limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the U.S. Securities and Exchange Commission, the U.S. Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited. In addition, issuers (including governments) in emerging market countries may have less financial stability than in other countries. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. There is also the potential for unfavorable action such as embargo and acts of war. As a result, there will tend to be an increased risk of price volatility in investments in emerging market countries, which may be magnified by currency fluctuations relative to the U.S. dollar. Settlement and asset custody practices for transactions in emerging markets may differ from those in developed markets. Such differences may include possible delays in settlement and certain settlement practices, such as delivery of securities prior to receipt of payment, which increase the likelihood of a “failed settlement.” Failed settlements can result in losses. For these and other reasons, investments in emerging markets are often considered speculative.

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Equity Investing Risk. The market prices of equity securities owned by the Fund may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer, such as management performance, financial leverage, non-compliance with regulatory requirements, and reduced demand for the issuer's goods or services. The values of equity securities also may decline due to general industry or market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, or adverse investor sentiment generally. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

Financial Institutions Risk. Some instruments are issued or guaranteed by financial institutions, such as banks and brokers, or are collateralized by securities issued or guaranteed by financial institutions. Changes in the creditworthiness of any of these institutions may adversely affect the values of instruments of issuers in financial industries. Financial institutions may be particularly sensitive to certain economic factors such as interest rate changes, adverse developments in the real estate market, fiscal and monetary policy and general economic cycles. Adverse developments in banking and other financial industries may cause the Fund to underperform relative to other funds that invest more broadly across different industries or have a smaller exposure to financial institutions. Changes in governmental regulation and oversight of financial institutions may have an adverse effect on the financial condition or the earnings or operations of a financial institution and on the types and amounts of businesses in which a financial institution may engage. An investor may be delayed or prevented from exercising certain remedies against a financial institution. The amount of the Fund's assets that may be invested in any financial institution, or financial institutions generally, may be limited by applicable law.

Financial Sector Risk. Financial services companies are subject to extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, the interest rates and fees they can charge, the scope of their activities, the prices they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds and can fluctuate significantly when interest rates change or due to increased competition. In addition, deterioration of the credit markets generally may cause an adverse impact in a broad range of markets, including U.S. and international credit and interbank money markets generally, thereby affecting a wide range of financial institutions and markets. Certain events in the financial sector may cause an unusually high degree of volatility in the financial markets, both domestic and foreign, and cause certain financial services companies to incur large losses. Securities of financial services companies may experience a dramatic decline in value when such companies experience substantial declines in the valuations of their assets, take action to raise capital (such as the issuance of debt or equity securities), or cease operations. Credit losses resulting from financial difficulties of borrowers and financial losses associated with investment activities can negatively impact the sector. Insurance companies may be subject to severe price competition. Adverse economic, business or political developments could adversely affect financial institutions engaged in mortgage finance or other lending or investing activities directly or indirectly connected to the value of real estate.

Frontier Markets Risks. Investments in frontier markets may be more volatile and less liquid than investments in more developed markets or in other emerging market countries. Some of these markets may have relatively unstable governments, economies based on only a few industries and securities markets that trade only a limited number of securities. Many frontier markets do not have well-developed regulatory systems and disclosure standards may be less stringent than those of more developed markets. The risks of expropriation, nationalization, and social, political, and economic instability are greater in frontier markets than in more developed markets. These risks, which are characteristic of many emerging markets generally, may be especially heightened in frontier markets, due to political, economic, financial, or other factors.

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and movements in the securities or index underlying the derivatives or movements in the prices of the Fund's investments that are the subject of such hedge. The prices of futures and other exchange-traded derivatives, for a number of reasons, may not correlate perfectly with movements in the securities or index underlying them. For example, participants in the futures markets and in markets for other exchange-traded derivatives are subject to margin deposit requirements. Such requirements may cause investors to take actions with respect to their derivatives positions that they would not otherwise take. The margin requirements in the derivatives markets may be less onerous than margin requirements in the securities markets in general, and as a result those markets may attract more speculators than the securities markets do. Increased participation by speculators in those markets may cause temporary price distortions. Due to the possibility of price distortion, even a correct forecast of general market trends by the Adviser still may not result in a successful derivatives activity over a very short time period. The risk of a position in a futures contract or other exchange-traded derivative may be very large compared to the relatively low level of margin the Fund is required to deposit. In many cases, a relatively small price movement in a futures contract may result in immediate and substantial loss or gain to the investor relative to the size of a required margin deposit. The Fund will incur brokerage fees in connection with its exchange-traded derivatives transactions. The Fund will typically be required to post margin with its futures commission merchant in connection with its transactions in futures contracts and other exchange-traded derivatives. In the event of an insolvency of the futures commission merchant or a clearing house, the Fund may not be able to recover all (or any) of the margin it has posted with the futures commission merchant, or to realize the value of any increase in the price of its positions, or it may experience a significant delay in doing so. The Fund also may be delayed or prevented from recovering margin or other amounts deposited with a futures commission merchant or futures clearinghouse. The Commodity Futures Trading Commission (the “CFTC”) and the various exchanges have established limits referred to as “speculative position limits” on the maximum net long or net short positions that any person and certain affiliated entities may hold or control in a particular futures contract. Trading limits are imposed on the number of contracts that any person may trade on a particular trading day. An exchange may order the liquidation of positions found to be in violation of these limits and it may impose sanctions or restrictions. In addition, the Dodd-Frank Act requires the CFTC to establish speculative position limits on certain commodity futures contracts and their economically equivalent futures, options and swaps. Regulatory action taken by the CFTC to establish these additional position limits may adversely affect the market liquidity of the futures, options and economically equivalent derivatives in which the Fund may invest. It is possible that, as a result of such limits, the Fund's Adviser will be precluded from taking positions in certain futures contracts or over-the-counter derivatives as a result of positions held by other clients of the Adviser or by the Adviser or its affiliates themselves.

Futures contracts and other exchange-traded derivatives traded on markets outside the U.S. are not generally subject to the same level of regulation by the CFTC or other U.S. regulatory entities as contracts traded in the U.S., including without limitation as to the execution, delivery, and clearing of transactions. U.S. regulators neither regulate the activities of a foreign exchange, nor have the power to compel enforcement of the rules of the foreign exchange or the laws of the foreign country in question. Margin and other payments made by the Fund may not be afforded the same protections as are afforded those payments in the U.S., including in connection with the insolvency of an executing or clearing broker or a clearinghouse or exchange. Certain foreign futures contracts and other exchange-traded derivatives may be less liquid and more volatile than U.S. contracts.

Geographic Focus Risk. The performance of a fund that is less diversified across countries or geographic regions will be closely tied to market, currency, economic, political, environmental, or regulatory conditions and developments in the countries or regions in which the fund invests, and may be more volatile than the performance of a more geographically-diversified fund.

China. The economy of China differs, often unfavorably, from the U.S. economy in such respects as structure, general development, government involvement, wealth distribution, rate of inflation, growth rate, allocation of resources and capital reinvestment, among others. Under China's political and economic system, the central government has historically exercised substantial control over virtually every sector of the Chinese economy through administrative regulation and/or state ownership. Since 1978, the Chinese government has been, and is expected to continue, reforming its economic policies, which has resulted in less direct central and local government control over the business and production activities of Chinese enterprises and companies. Notwithstanding the economic reforms instituted by the Chinese government and the Chinese Communist Party, actions of the Chinese central and local government authorities continue to have a substantial effect on economic conditions in China, which could affect the public and private sector companies in which the Fund invests. In the past, the Chinese government has from time to time taken actions that influence the prices at which certain goods may be sold, encourage companies to invest or concentrate in particular industries, induce mergers between companies in certain industries and induce private

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companies to publicly offer their securities to increase or continue the rate of economic growth, control the rate of inflation or otherwise regulate economic expansion. It may do so in the future as well. The Chinese government may also intervene or seek to control the operations, structure, or ownership of Chinese companies, including with respect to foreign investors of such companies. Such actions and a variety of other centrally planned or determined activities by the Chinese government could have a significant adverse effect on economic conditions in China, the economic prospects for, and the market prices and liquidity of, the securities of Chinese companies and the payments of dividends and interest by Chinese companies. In addition, expropriation, including nationalization, confiscatory taxation, political, economic or social instability or other developments could adversely affect and significantly diminish the values of the Chinese companies in which the Fund invests. The Chinese economy and financial markets have experienced high levels of growth in recent years; any actual or perceived reduction or curtailment in those levels of growth in the future would likely have a substantial adverse impact on the values of Chinese companies. These factors and others could negatively affect the value and liquidity of the Fund. The Fund may invest in shares of Chinese companies traded on stock markets in Mainland China or Hong Kong. These stock markets have recently experienced high levels of volatility, which may continue in the future. The Hong Kong stock market may behave differently from the Mainland China stock market and there may be little to no correlation between the performance of the Hong Kong stock market and the Mainland China stock market.

The Fund may gain investment exposure to certain Chinese companies through variable interest entity (“VIE”) structures. Such investments are subject to the investment risks associated with the Chinese-based company. The VIE structure enables foreign investors, such as the Fund, to obtain investment exposure to a Chinese company in situations in which the Chinese government has limited or prohibited non-Chinese ownership of such company. Although VIEs are a common industry practice and well known to officials and regulators in China, until recently, VIEs were not formally recognized under Chinese law. However, in late 2021, the Chinese government signaled its interest in implementing filing requirement rules that would both affirm the legality of VIE structures and regulate them. How these filing requirements will operate in practice, and what will be required for approval, remains unclear. While there is optimism that these actions will reduce uncertainty over Chinese actions on VIEs, there is also caution given how unresolved the process is. Until these rules are finalized, and potentially afterwards depending on how they are implemented, there remains significant uncertainty associated with VIE investments.

The VIE structure does not involve direct equity ownership in a China-based company, but rather involves claims to the China-based company's profits and control of the assets that belong to the China-based company through contractual arrangements. Intervention by the Chinese government with respect to the VIE structure could significantly affect the Chinese operating company's performance and thus, the value of the Fund's investment through a VIE structure, as well as the enforceability of the contractual arrangements of the VIE structure. In the event of such an occurrence, the Fund, as a foreign investor, may have little or no legal recourse. In addition to the risk of government intervention, investments through a VIE structure are subject to the risk that the China-based company (or its officers, directors, or Chinese equity owners) may breach the contractual arrangements, or Chinese law changes in a way that adversely affects the enforceability of the arrangements, or the contracts are otherwise not enforceable under Chinese law, in which case the Fund may suffer significant losses on its investments through a VIE structure with little or no recourse available.

From time to time, certain of the companies in which a Fund may invest may operate in, or have dealings with, countries subject to sanctions or embargoes imposed by the U.S. government and the United Nations and/or in countries identified by the U.S. government as state sponsors of terrorism. One or more of these companies may be subject to constraints under U.S. law or regulations which could negatively affect the company's performance. Additionally, one or more of these companies may suffer damage to its reputation if it is identified as a company which invests or deals with countries which are identified by the U.S. government as state sponsors of terrorism or subject to sanctions. As an investor in such companies, the Fund will be indirectly subject to these risks.

Unexpected political, regulatory and diplomatic events, such as the U.S.-China “trade war” that intensified in 2018, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. The current political climate and the further escalation of a trade war between China and the United States may have an adverse effect on both the U.S. and Chinese economies, as each country has recently imposed tariffs on the other country's products. Some U.S. politicians have recently sought to limit certain U.S. investors from investing in Chinese companies. Events such as these and their impact on the Funds are difficult to predict and it is unclear whether further tariffs may be imposed or other escalating actions may be taken in the future.

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South Korea. In addition, economic and political developments of South Korean neighbors may have an adverse effect on the South Korean economy. Substantial political tensions exist between North Korea and South Korea and, recently, these political tensions have escalated. The outbreak of hostilities between the two nations, or even the threat of such an outbreak, will likely adversely impact the South Korean economy. In addition, South Korea's economic growth potential has recently been on a decline, mainly because of a rapidly aging population and structural problems. Among these structural concerns are the country's underdeveloped financial markets and a general lack of regulatory transparency. The restructuring of the South Korean economy, including the creation of a mechanism for bankrupt firms to exit the market, remains an important unfinished task. These factors may adversely affect the South Korean economy and cause a diversion of corporate investment to China and other lower wage countries. South Korea's economic growth potential is susceptible to problems from large scale emigration, rigid labor regulations and ongoing labor relations issues.

Taiwan. Taiwan's geographic proximity and history of political contention with China have resulted in ongoing tensions between the two countries. These tensions may materially affect the Taiwanese economy and its securities market. Taiwan's economy is export-oriented, so it depends on an open world trade regime and remains vulnerable to fluctuations in the world economy. Rising labor costs and increasing environmental consciousness have led some labor-intensive industries to relocate to countries with cheaper work forces, and continued labor outsourcing may adversely affect the Taiwanese economy.

Indexing Strategy/Index Tracking Risk. The Fund is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities. The Fund will seek to replicate Index returns, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. The Fund generally will buy and will not sell a security included in the Index as long as the security is part of the Index regardless of any sudden or material decline in value or foreseeable material decline in value of the security, even though the Adviser may make a different investment decision for other actively managed accounts or portfolios that hold the security. As a result, the Fund's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index (in absolute terms and by comparison with other indices) and, consequently, the performance, volatility, and risk of the Fund. Errors in index data, index computations or the construction of the Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Fund's return may not match the return of the Index for a number of reasons. For example, the return on the sample of securities purchased by the Fund (or the return on securities not included in the Index) to replicate the performance of the Index may not correlate precisely with the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Fund may not be fully invested at times, either as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to track the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Fund's return and that of the Index. Changes in the composition of the Index and regulatory requirements also may impact the Fund's ability to match the return of the Index. The Adviser may apply one or more “screens” or investment techniques to refine or limit the number or types of issuers included in the Index in which the Fund may invest. Application of such screens or techniques may result in investment performance below that of the Index and may not produce results expected by the Adviser. Index tracking risk may be heightened during times of increased market volatility or other unusual market conditions.

Information Technology Sector Risk. Market or economic factors impacting information technology companies could have a major effect on the value of the Fund's investments. The value of stocks of information technology companies is particularly vulnerable to rapid changes in technology product cycles, rapid product obsolescence, government regulation and competition, both domestically and internationally, including competition from foreign competitors with lower production costs. Like other technology companies, information technology companies may have limited product lines, markets, financial resources or personnel. Stocks of technology companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Information technology companies are heavily dependent on patent and intellectual property rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

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Large-Capitalization Securities Risk. Securities issued by large-capitalization companies may present risks not present in smaller companies. For example, larger companies may be unable to respond as quickly as smaller and mid-sized companies to competitive challenges or to changes in business, product, financial, or other market conditions. Larger companies may not be able to maintain growth at the high rates that may be achieved by well-managed smaller and mid-sized companies, especially during strong economic periods. Returns on investments in securities of large companies could trail the returns on investments in securities of smaller and mid-sized companies.

Leveraging Risk. Borrowing transactions, reverse repurchase agreements, certain derivatives transactions, securities lending transactions and other investment transactions such as when-issued, delayed-delivery, or forward commitment transactions may create investment leverage. If the Fund engages in transactions that have a leveraging effect on the Fund's investment portfolio, the value of the Fund will be potentially more volatile and all other risks will tend to be compounded. This is because leverage generally creates investment risk with respect to a larger base of assets than the Fund would otherwise have and so magnifies the effect of any increase or decrease in the value of the Fund's underlying assets. The use of leverage is considered to be a speculative investment practice and may result in losses to the Fund. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The use of leverage may cause the Fund to liquidate positions when it may not be advantageous to do so to satisfy repayment, interest payment, or margin obligations or to meet asset segregation or coverage requirements.

LIBOR Risk. The Fund's payment obligations, financing terms and investments in certain instruments (including debt securities and derivatives) may rely in some fashion upon the London-Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration (the administrator of LIBOR), that banks offer to charge one another for the use of short-term money. In 2017, the U.K. Financial Conduct Authority announced its intention to cease compelling banks to provide the quotations needed to sustain LIBOR after 2021. IBA ceased publication of most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of a majority of U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. Actions by regulators have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Various financial industry groups have been planning for the transition away from LIBOR and markets are developing in response to these new rates, but questions around the liquidity of the new rates and how to appropriately adjust these rates to eliminate any economic value transfer at the time of transition remain a significant concern. The transition away from and eventual elimination of LIBOR may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include “fall back” provisions addressing the transition from LIBOR. Uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by the Fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Fund.

Liquidity Risk. Liquidity risk is the risk that the Fund may not be able to dispose of investments or close out derivatives transactions readily at a favorable time or prices (or at all) or at prices approximating those at which the Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for the Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. The Fund may seek to borrow money to meet its obligations (including, among other things, redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity the Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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Market Disruption and Geopolitical Risk. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of the Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of the Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Fund's investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by the Fund. To the extent the Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

Market Risk. Market prices of investments held by the Fund will go up or down, sometimes rapidly or unpredictably. The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile, and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in actual or perceived creditworthiness of issuers and general market liquidity. Even if general economic conditions do not change, the value of an investment in the Fund could decline if the particular industries, sectors or companies in which the Fund invests do not perform well or are adversely affected by events. Further, legal, political, regulatory and tax changes also may cause fluctuations in markets and securities prices. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Mid-Capitalization Securities Risk. The securities of mid-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of mid-sized companies may trade less frequently and in smaller volumes than more widely held securities. The prices of these securities may fluctuate more sharply than those of other securities, and the Fund may experience some difficulty in establishing or closing out positions in these securities at prevailing market prices. There may be less publicly available information about the issuers of these securities or less market interest in these securities than in the case of larger companies, both of which can cause significant price volatility. Some securities of mid-sized issuers may be illiquid or may be restricted as to resale. Returns on investments in securities of mid-capitalization companies could trail the returns on investments in securities of larger or smaller companies.

Non-U.S. Securities Risk. Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Because non-U.S. securities are typically denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets, to the extent they are non-U.S. dollar denominated, may be affected favorably or unfavorably by currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect the Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange

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controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of the Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where the Fund invests could cause the Fund's investments in that country to experience gains or losses.

Risk of Investment in Other Pools. If the Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. The Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of the Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. The Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by the Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest the Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by the Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so.

Settlement Risk. Markets in different countries have different clearance and settlement procedures and in certain markets there have been times when settlements have been unable to keep pace with the volume of transactions. Delays in settlement may increase credit risk to the Fund, limit the ability of the Fund to reinvest the proceeds of a sale of securities, hinder the ability of the Fund to lend its portfolio securities, and potentially subject the Fund to penalties for its failure to deliver to on-purchasers of securities whose delivery to the Fund was delayed. Delays in the settlement of securities purchased by the Fund may limit the ability of the Fund to sell those securities at times and prices it considers desirable, and may subject the Fund to losses and costs due to its own inability to settle with subsequent purchasers of the securities from it. The Fund may be required to borrow monies it had otherwise expected to receive in connection with the settlement of securities sold by it, in order to meet its obligations to others. Limits on the ability of the Fund to purchase or sell securities due to settlement delays could increase any variance between the Fund's performance and that of its benchmark index.

Unconstrained Sector Risk. The Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. When the Fund focuses its investments in a particular industry or sector, financial, economic, business, and other developments affecting issuers in that industry, market, or economic sector will have a greater effect on the Fund than if it had not focused its assets in that industry, market, or economic sector, which may increase the volatility of the Fund. Any such investment focus may also limit the liquidity of the Fund. In addition, investors may buy or sell substantial amounts of the Fund's shares in response to factors affecting or expected to affect an industry, market, or economic sector in which the Fund focuses its investments, resulting in extreme inflows or outflows of cash into and out of the Fund. Such extreme cash inflows and outflows might affect management of the Fund adversely.

Valuation Risk. Some portfolio holdings, potentially a large portion of the Fund's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. Technological issues or other service disruption issues involving third-party service providers may cause the Fund to value its investments incorrectly. In addition, there

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Additional Information About Non-Principal Investment Strategies and Risks

Conflicts of Interest Risk. An investment in the Fund will be subject to a number of actual or potential conflicts of interest. For example, the Adviser or its affiliates may provide services to the Fund, such as securities lending agency services, custodial, administrative, bookkeeping, and accounting services, transfer agency and shareholder servicing, securities brokerage services, and other services for which the Fund would compensate the Adviser and/or such affiliates. The Fund may invest in other pooled investment vehicles sponsored, managed, or otherwise affiliated with the Adviser. There is no assurance that the rates at which the Fund pays fees or expenses to the Adviser or its affiliates, or the terms on which it enters into transactions with the Adviser or its affiliates will be the most favorable available in the market generally or as favorable as the rates the Adviser or its affiliates make available to other clients. Because of its financial interest, the Adviser will have an incentive to enter into transactions or arrangements on behalf of the Fund with itself or its affiliates in circumstances where it might not have done so in the absence of that interest, provided that the Adviser will comply with applicable regulatory requirements.

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

The foregoing does not purport to be a comprehensive list or complete explanation of all potential conflicts of interests which may affect the Fund. The Fund may encounter circumstances, or enter into transactions, in which conflicts of interest that are not listed or discussed above may arise.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund and its service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Adviser, or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and pro-

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tocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

Index Construction Risk. A security included in the Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently the Fund's holdings may not exhibit returns consistent with that characteristic or exposure.

Index Licensing Risk. It is possible that the license under which the Adviser or the Fund is permitted to replicate or otherwise use the Index will be terminated or may be disputed, impaired or cease to remain in effect. In such a case, the Adviser may be required to replace the Index with another index which it considers to be appropriate in light of the investment strategy of the Fund. The use of any such substitute index may have an adverse impact on the Fund's performance. In the event that the Adviser is unable to identify a suitable replacement for the Index, it may determine to terminate the Fund.

Securities Lending Risk. The Fund may lend portfolio securities in an amount not to exceed 40% of the value of its net assets. For these purposes, net assets shall exclude the value of all assets received as collateral for the loan. Such loans may be terminated at any time. Any such loans must be continuously secured by collateral (either cash or other obligations as may be permitted under the Fund's securities lending program) maintained on a current basis in an amount at least equal to the market value of the securities loaned by the Fund, marked to market each trading day. In a loan transaction, as compensation for lending its securities, the Fund will receive a portion of the dividends or interest accrued on the securities held as collateral or, in the case of cash collateral, a portion of the income from the investment of such cash. In addition, the Fund will receive the amount of all dividends, interest and other distributions on the loaned securities. However, the borrower has the right to vote the loaned securities. The Fund will call loans to vote proxies if a material issue affecting the investment is to be voted upon. Efforts to recall such securities promptly may be unsuccessful, especially for foreign securities or thinly traded securities, and may involve expenses to the Fund. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. Should the borrower of the securities fail financially, the Fund may experience delays in recovering the securities or exercising its rights in the collateral. Loans are made only to borrowers that are deemed by the securities lending agent to be of good financial standing. In a loan transaction, the Fund will also bear the risk of any decline in value of securities acquired with cash collateral. The Fund expects to invest cash collateral in a pooled investment vehicle advised by the Adviser. With respect to index funds, to the extent the collateral provided or investments made with cash collateral differ from securities included in the relevant Index, such collateral or investments may have a greater risk of loss than the securities included in the Index. In addition, the Fund will be subject to the risk that any income generated by reinvesting cash collateral is lower than any fees the Fund has agreed to pay a borrower.

Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

The Fund is a separate, diversified series of the State Street Institutional Investment Trust (the “Trust”), which is an open-end management investment company organized as a business trust under the laws of the Commonwealth of Massachusetts.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and, subject to the oversight of the Board, is responsible for the investment management of the Fund. The Adviser provides an investment management program for the Fund and manages the investment of the Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the U.S. Securities and Exchange Commission (“SEC”) under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

The Fund has entered into an investment advisory agreement with the Adviser, pursuant to which the Adviser will manage the Fund's assets for compensation paid at the annual rate of 0.14% of the Fund's average daily net assets. For the fiscal year ended December 31, 2021, the Fund's effective management fee paid was 0.01%.

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.12% of average daily net assets on an annual basis. This waiver and/or reimbursement arrangement may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees.

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Adviser manages the Fund using a team of investment professionals. The team approach is used to create an environment that encourages the flow of investment ideas. The portfolio managers within the team work together in a cohesive manner to develop and enhance techniques that drive the investment process for the respective investment strategy. This approach requires portfolio managers to share a variety of responsibilities, including investment strategy and analysis, while retaining responsibility for the implementation of the strategy within any particular portfolio. The approach also enables the team to draw upon the resources of other groups within SSGA. The portfolio management team is overseen by the SSGA Investment Committee.

The professionals primarily responsible for the day-to-day management of the Fund include the following:

Thomas Coleman, CFA, is a Vice President of SSGA and the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. Within this group, Mr. Coleman is the Emerging Markets Strategy leader and, as such, he is responsible for the management of a variety of commingled, segregated, and exchange traded products benchmarked to international indices, including MSCI Emerging Markets and ACWI indices, as well as S&P Emerging Markets indices. Mr. Coleman is also responsible for domestic strategies benchmarked to Russell, Standard & Poor's, and NASDAQ indices. Prior to assuming his current role in April 2004, he managed SSGA's International Structured Products Group Operations Team. Mr. Coleman holds a Bachelor of Science in Finance and Accounting from Boston College and a Master of Business Administration from Babson College. He also earned the Chartered Financial Analyst (CFA) designation and is a member of CFA Society Boston, Inc.

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State Street Global Markets, LLC, where he helped to build the Global Exposure Solutions business. This group created and managed portfolios that were designed to meet the short-term market exposure needs of institutional clients. Prior to this, Mr. Feehily had been Head of the U.S. Passive Equity Team within SSGA, which he originally joined in 1997. He began his career at State Street in 1993 within the Global Services division, where he was a member of the Performance & Analytics team and was one of the founding members of the firm's Private Edge business, which helped to analyze clients' private market investments such as venture capital, corporate finance, and real estate. Mr. Feehily received a Bachelor of Science from Babson College in Finance, Investments, and Economics. He received a Master of Business Administration in Finance from Bentley College and also earned the Chartered Financial Analyst (CFA) designation. Mr. Feehily is a member of the CFA Institute and CFA Society Boston, Inc. He is also a former member of the FTSE/Russell Index Client Advisory Board and the S&P Index Advisory Committee. He is registered as an Advising Representative with all Canadian Provincial Securities Commissions under State Street Global Advisor Limited's (Canada) Portfolio Manager registration category. He currently serves as an Executive Sponsor for the Inclusion & Diversity Talent Acquisition Pillar at SSGA.

Olga Winner, CFA, is a Vice President of SSGA and the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. She is responsible for the management of several domestic, international developed and emerging market strategies, including separate accounts, commingled funds, mutual funds and ETFs. Additionally, Ms. Winner manages hedged and futures overlay strategies. Prior to joining SSGA, Ms. Winner worked as an acquisitions associate at Boston Capital Partners, a real estate investment firm, analyzing investment opportunities. She holds a Master of Business Administration and a Master of Science in Finance from the Carroll School of Management at Boston College and a Bachelor of Science in Finance from the University of Massachusetts. She also earned the Chartered Financial Analyst (CFA) designation and is a member of CFA Society Boston, Inc.

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Fund is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator and custodian for the Fund. The Adviser and the Fund each bear a portion of the fee paid to State Street for providing sub-administration and custodian services with respect to the Fund.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

The Trustees of the Trust oversee generally the operations of the Fund and the Trust. The Trust enters into contractual arrangements with various parties, including, among others, the Fund's investment adviser, custodian, transfer agent, and accountants, who provide services to the Fund. Shareholders are not parties to any such contractual arrangements or intended beneficiaries of those contractual arrangements, and those contractual arrangements are not intended to create in any shareholder any right to enforce them directly against the service providers or to seek any remedy under them directly against the service providers.

This Prospectus provides information concerning the Trust and the Fund that you should consider in determining whether to purchase shares of the Fund. Neither this Prospectus, nor the related SAI, is intended, or should be read, to be or to give rise to an agreement or contract between the Trust or the Fund and any investor, or to give rise to any rights in any shareholder or other person other than any rights under federal or state law that may not be waived.

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Shareholder Information

Determination of Net Asset Value

The Fund determines its NAV per share once each business day as of the scheduled close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in the Fund. The NAV of each class of the Fund's Shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding.As noted in this Prospectus, the Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when the Fund does not price its shares. Consequently, the NAV of the Fund's Shares may change on days when shareholders are not able to purchase or redeem the Fund's Shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. The Fund values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Fund's Board, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price the Fund would have received had it sold the investment. To the extent that the Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published NAVs per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

Choosing a Share Class

The Fund offers three classes of shares through this Prospectus: Class A, Class I and Class K, available to you subject to the eligibility requirements set forth below.

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All classes of the Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. The availability of shares of a particular class through a given Financial Intermediary will depend on the policies and procedures of the Financial Intermediary. The Fund, the Distributor, the Adviser and the Transfer Agent do not provide advice or make recommendations regarding Fund share classes and do not verify that you have invested in the share class most appropriate for your investment needs. You should choose the class with the expense structure that best meets your needs and for which you are eligible. Some factors to consider are the amount you plan to invest, the time period before you expect to sell your shares, whether you might invest more money in the Fund in the future, and the nature of your arrangement with a Financial Intermediary. Your investment professional can help you choose a share class that is appropriate for your investment needs.

When you buy Class A shares, the initial sales load is deducted from the amount you invest, unless you qualify for an initial sales load waiver. This means that less money will be invested in the Fund immediately. Class A shares have a Rule 12b-1 fee of 0.25% per year. A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

The chart below summarizes the features of the different share classes. This chart is only a general summary, and you should read the description of the Fund's expenses in the Fund Summary in this Prospectus.

	Class A	Class I	Class K
Availability	Available to the general public through certain Financial Intermediaries.	Limited to certain investors serviced through a Financial Intermediary receiving a fee from the applicable Fund for shareholder servicing or similar services.	Limited to certain investors, including certain qualified recordkeepers, financial institutions and employer-sponsored retirement plans.
Minimum Initial Investment	$2,000. The investment minimum may be modified, waived or reduced for certain types of investors (e.g., 401(k) or 403(b) plans) and investments as well as for certain fee-based programs where an agreement is in place.	There is no minimum investment for Class I shares.	There is no minimum investment for Class K shares.
Maximum Investment	None.	None.	None.
Initial (Front-End) Sales Charge	Yes. 5.25%, payable at time of purchase. Lower sales charges are available for larger investments. See the chart under “Class A” section of this Prospectus.	No. Entire purchase price is invested in shares of the Fund.	No. Entire purchase price is invested in shares of the Fund.

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	Class A	Class I	Class K
Deferred (CDSC) Sales Charge	No, except for purchases of $1,000,000 or more that are redeemed within 18 months after purchase.	No.	No.
Distribution and Service (Rule 12b-1) Fees	0.25% annual fee.	No.	No.
Redemption Fees	No.	No.	No.

Class A

Class A shares are available to the general public for investment through qualified recordkeepers with a distribution and/or fund servicing agreement maintained with SSGA FD.

When you buy Class A shares, you pay an initial (or front-end) sales charge at the time of your investment, which is included in the offering price, unless you qualify for a sales charge reduction or waiver. This fee is deducted from the amount you invest, and the remainder of your money is used to buy shares in the Fund. The table below shows the amount of sales charge you would pay at different levels of investment and the commissions paid to Financial Intermediaries at each level of investment. The actual sales charge you pay may vary slightly from the rates disclosed due to rounding.

Amount of Purchase Payment	Sales Charge as a % of Offering Price	Sales Charge as a % of Net Amount Invested	Financial Intermediary Compensation as a % of Offering Price
Less than $50,000	5.25%	5.54%	4.75%
$50,000-$99,999	4.50%	4.71%	4.00%
$100,000-$249,999	3.50%	3.63%	3.25%
$250,000-$499,999	2.50%	2.56%	2.25%
$500,000-$999,999	2.00%	2.04%	1.75%
$1,000,000 or more	None	None	Advanced Commission^{1, 2}

¹	Class A advanced commission for purchases over $1 million:

1.00%	First $3 million
Plus 0.50%	Next $12 million
Plus 0.25%	Over $15 million

If you purchase $1,000,000 or more of Class A shares of the Fund, you will not be assessed a sales charge at the time of purchase. SSGA FD pays broker-dealers advanced commissions that are calculated on a year-by-year basis based on the amounts invested during that year. Accordingly, with respect to additional purchase amounts, the advanced commission breakpoint resets annually to the first breakpoint on the anniversary of the first purchase. You may be charged a deferred sales charge of 1.00% of the lesser of the original cost of the shares being redeemed or your redemption proceeds if you redeem your shares within 18 months after purchase.

Reducing Your Class A Sales Charge

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your spouse or domestic partner and children under the age of 21 who share your residential address. It is your responsibility when investing to inform your Financial Intermediary or the State Street Funds that you would like to have one or more of the State Street Funds linked together for purposes of reducing the initial sales charge.

1.	Your account(s);
2.	Account(s) of your spouse or domestic partner;
3.	Account(s) of children under the age of 21 who share your residential address;
4.	Trust accounts established by any of the individuals in items (1) through (3) above. If the person(s) who established the trust is deceased, the trust account may be aggregated with the account(s) of the primary beneficiary of the trust;
5.	Solely controlled business accounts; and
6.	Single-participant retirement plans of any of the individuals in items (1) through (3) above.

Gifting of Shares. If you make a gift of shares, upon your request, you may combine purchases, if made at the same time, under right of accumulation of Class A, Class I and Class N shares of a State Street Fund (other than any shares of money market funds) at the sales charge discount allowed for the combined purchase. The receiver of the gift may also be entitled to a prospective reduction in sales charges in accordance with the Fund's right of accumulation or other provisions. You or the receiver of the gift must provide certain account information to State Street or their agents at the time of purchase to exercise this right.

Letter of Intent. In order to immediately reduce your Class A sales charge, you may sign a Letter of Intent stating your intention to buy a specified amount of Class A shares of one or more State Street Funds within a 13-month period at the reduced sales charge rates applicable to the aggregate amount of the intended purchases stated in the Letter. Purchases of Class A shares of one or more State Street Funds you make over the 13- month period will be combined and you will pay the same sales charge on the new Class A shares that you would have paid if all shares were purchased at once. The 13-month Letter of Intent period commences on the day that the Letter of Intent is received by the Fund or your Financial Intermediary. Purchases submitted not more than three months prior to the date the Letter of Intent is received are considered in determining the level of sales charge that will be paid pursuant to the Letter of Intent; however, the Letter of Intent will not result in any reduction in the amount of any previously paid sales charge. In addition, investors do not receive credit for shares purchased by the reinvestment of distributions.

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Waiver Of The Class A Sales Charge

A sales charge (“load”) may not be imposed on Class A shares of the Fund if the shares were:

1.	Acquired through the reinvestment of dividends and capital gain distributions.
2.	Acquired in exchange for shares of another Class A State Street Fund that were previously assessed a sales charge. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares at the same CDSC rate.
3.	Bought in State Street Funds that do not offer Class N (no load) shares¹ by officers, directors or trustees, retirees and employees and their immediate family members (i.e., spouses, domestic partners, children, grandchildren, parents, grandparents, and any dependent of the person, as defined in Section 152 of the Internal Revenue Code of 1986 (the “Code”)) of:

•	The State Street Funds
•	State Street Corporation and its subsidiaries and affiliates

4.	Bought by employees of:

•

DST Asset Manager Solutions, Inc. and its subsidiaries and affiliates.

•

Financial Intermediaries of financial institutions that have entered into selling agreements with the Fund or SSGA FD and their subsidiaries and affiliates (or otherwise have an arrangement with a Financial Intermediary or financial institution with respect to sales of Fund Shares). This waiver includes the employees' immediate family members (i.e., spouses, domestic partners, children, grandchildren, parents, grandparents and any dependent of the employee, as defined in Section 152 of the Code).

5.	Bought by:

•	Authorized retirement plans serviced or sponsored by a Financial Intermediary, provided that such Financial Intermediary has entered into an agreement with SSGA FD or with the Fund with respect to such purchases at NAV.
•	Investors who are directly rolling over or transferring shares from an established State Street Fund or State Street qualified retirement plan. Rolling over or transferring shares involves the transferring of shares (in-kind); there is no cash movement associated with the transaction.
•	Clients of Financial Intermediaries that (i) charge an ongoing fee for advisory, management, consulting or similar services, or (ii) have entered into an agreement with SSGA FD to offer Class A shares through a no-load network or platform, or self-directed brokerage accounts that may or may not charge transaction fees to customers.
•	Insurance company separate accounts.
•	Tuition Programs that qualify under Section 529 of the Code.

6.	Bought with proceeds from the sale of Class A shares of a State Street Fund, but only if the purchase is made within 90 days of the sale or distribution. Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.
7.	Bought in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which the Fund is a party. However, you may pay a CDSC when you sell the Fund Shares you received in connection with the plan of reorganization.

Additional Sales Charge Waiver Disclosure

¹	State Street Funds that offer Class N Shares include: State Street Defensive Emerging Markets Equity Fund (SSEMX), State Street International Stock Selection Fund (SSAIX) and State Street S&P 500 Index Fund (SVSPX).

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How the CDSC is Calculated

The State Street Funds calculate the CDSC by treating all purchases made in a given month as though they were made on the first day of the month.

You should retain any records necessary to substantiate historical costs because SSGA FD, the Fund, the transfer agent and your Financial Intermediary may not maintain such information.

Waiver of the CDSC

In the following situations, no CDSC is imposed on redemptions of Class A shares of the Fund:

1.	If you participate in the Automatic Withdrawal Plan. Redemptions made on a regular periodic basis (e.g. monthly) will not be subject to any applicable CDSC if they are, in the aggregate, less than or equal to 10% annually of the current market value of the account balance. Redemptions made as part of a required minimum distribution are also included in calculating amounts eligible for this waiver. For information on the Automatic Withdrawal Plan, please see Service Options.
2.	If you are a registered participant or beneficial owner of an account and you die or become disabled (as defined in Section 72(m)(7) of the Code). This waiver is only available for accounts open prior to the shareholder's or beneficiary's death or disability, and the redemption must be made within one year of such event. Subsequent purchases into such account are not eligible for the CDSC waiver. In order to qualify for this waiver, SSGA FD must be notified of such death or disability at the time of the redemption order and be provided with satisfactory evidence of such death or disability.
3.	Redemptions that represent a required minimum distribution from your IRA Account or other qualifying retirement plan but only if you are at least age 72 or age 70 ½ if you reached age 70 ½ prior to January 1, 2020. If you maintain more than one IRA, only the assets credited to the IRA that is invested in one or more of the State Street Funds are considered when calculating that portion of your minimum required distribution that qualifies for the waiver.
4.	A distribution from a qualified retirement plan by reason of the participant's retirement.
5.	Redemptions that are involuntary and result from a failure to maintain the required minimum balance in an account.
6.	Exchanges in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which the Fund is a party. However, you may pay a sales charge when you redeem the Fund Shares you receive in connection with the plan of reorganization.
7.	Exchanges for shares of the same class of another State Street Fund. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares. For purposes of the CDSC, shares will continue to age from the date of the original purchase of the Fund Shares.
8.	Redemption of shares purchased through employer sponsored retirement plans and deferred compensation plans. The CDSC, however, will not be waived if the plan redeems all of the shares that it owns on behalf of participants prior to the applicable CDSC period, as defined above.
9.	Redemptions as part of annual IRA custodial fees.
10.	Acquired through the reinvestment of dividends and capital gains distributions.

Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.

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Class A Account Reinstatement Privileges

Class I

Class I shares are available to the following categories of investors serviced through a Financial Intermediary receiving a fee from a Fund for shareholder servicing or similar services:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) that have entered into agreements with the Fund to purchase Class I shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund “supermarkets”;
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Defined contribution, defined benefit and other employer-sponsored employee benefit plans, whether or not qualified under the Code.

There is no minimum investment for Class I shares.

Class K

Class K shares are available to the following categories of investors:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) purchasing Fund Shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund "supermarkets";
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Qualified recordkeepers with an applicable agreement maintained with SSGA FD;
3.	Endowments and foundations, and defined contribution, defined benefit, and other employer-sponsored employee benefit plans, whether or not qualified under the Code;
4.	Certain other registered open-end investment companies whose shares are distributed by SSGA FD;
5.	Current or retired Directors or Trustees of the State Street Funds, officers and employees of SSGA, and any of its subsidiaries, such persons' spouses, and children under the age of 21, and trust accounts for which any of such person is a beneficiary;
6.	Qualified state tuition plans described in Section 529 of the Code and donor-advised charitable gift funds (subject to all applicable terms and conditions);
7.	Health Savings Accounts under Section 223 of the Code if such accounts are maintained by the Fund at an omnibus level;
8.	Collective investment trusts.

There is no minimum investment for Class K shares.

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How to Initiate a Purchase Request

Investing in the State Street Funds Through a Financial Intermediary

Account Applications and Other Documents. You may find many of the forms necessary to open an account online or by calling or writing to the State Street Funds. See Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

How to Pay for a Purchase

By Check. You may send a check to make initial or additional purchases to your fund account. Make your check payable to “State Street Funds” and include the appropriate fund name and account number (e.g., “State Street Emerging Markets Equity Index Fund—a/c #xxx”) in the memo section of the check.

By Exchange. You may purchase shares of a State Street Fund, provided the Fund's minimum investment is met, using the proceeds from the simultaneous redemption of shares of another State Street Fund of the same class. You may initiate an exchange by telephone, or by mail. See Exchanging Shares below.

Trade Dates-Purchases

If your purchase request is not in good order, it may be rejected.

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For further information about purchase transactions, consult our website at www.ssga.com or see Contacting the State Street Funds.

Other Purchase Policies You Should Know

Redeeming Shares

By Telephone. You may call the State Street Funds to request a redemption of shares. See Contacting the State Street Funds.

By Mail. You may send a written request to the State Street Funds to redeem from the Fund account or to make an exchange. See Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

Trade Date-Redemptions

The trade date for any redemption request received in good order will depend on the day and time the State Street Funds receive your request in good order and the manner in which you are redeeming.

How to Receive Redemption Proceeds

Regardless of the method the Fund uses to make a redemption payment, the Fund typically expects to pay out redemption proceeds on the next business day after a redemption request is received in good order. If you purchased State Street Fund Shares by check or an automatic investment program and you elect to redeem shares within 15 days of the purchase, you may experience delays in receiving redemption proceeds. In this case, the State Street Funds generally will postpone sending redemption proceeds until it can verify that the check or automatic investment program investment has been collected, but in no event will this delay exceed 15 days. There will be no such delay for redemptions following purchases paid by federal funds wire or by bank cashier's check, certified check or treasurer's check. The State Street Funds reserve the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund. The State Street Funds reserve the right to suspend the right of shareholder redemption or postpone the date of payment for more than seven days to the extent permitted by the 1940 Act.

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Under normal circumstances, the Fund expects to meet redemption requests by using cash or cash equivalents in its portfolio and/or selling portfolio assets to generate cash. The Fund also may pay redemption proceeds using cash obtained through borrowing arrangements (including under the Fund's line of credit, which is shared across all registered funds advised by SSGA FM (other than money market funds)) that may be available from time to time.

The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs (including through the realization of taxable gain) to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

During periods of deteriorating or stressed market conditions, when an increased portion of the Fund's portfolio may be comprised of less liquid investments, or during extraordinary or emergency circumstances, the Fund may be more likely to pay redemption proceeds with cash obtained through short-term borrowing arrangements (if available) or by giving you securities.

By Electronic Bank Transfer. You may have the proceeds of the fund redemption sent directly to a designated bank account. To establish the electronic bank transfer option on an account, you must designate a bank account by completing a special form or filling out the appropriate section of your account registration form. After the option is set up on your account, you can redeem shares by electronic bank transfer on a regular schedule (Automatic Withdrawal Plan) or from time to time. Your redemption request can be initiated by telephone, or by mail.

Other Redemption Policies that You Should Know

Address Changes. If your address of record has been changed within thirty (30) days of the redemption request, the request must be in writing and bear a medallion guarantee.

Significant/Unusual Economic or Market Activity. During periods of significant or unusual economic or market activity, you may encounter delays attempting to give instructions by phone.

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Minimum Account Size. If, due to your redemptions or exchanges, your account balance for the Fund falls below a minimum amount set by the Fund (presently, the minimum initial investment of your selected share class), the Fund may choose to redeem the shares in the account and mail you the proceeds. You will receive 60 days' notice that your account will be closed unless an investment is made to increase the account balance to the required minimum. Failure to bring your account balance to the required minimum within the prescribed period may result in the Fund closing your account at the NAV next determined on the day the account is closed, and mailing the proceeds to you at the address shown on the Fund's records.

Exchanging Shares

Share Class Conversions

Frequent-Trading Limits

Frequent, short-term trading, abusive trading practices and market timing (together, “Excessive Trading”), often in response to short-term fluctuations in the market, are not knowingly permitted by the State Street Funds. The State Street Funds do not accommodate frequent purchases and redemptions of Fund Shares by Fund shareholders. Excessive Trading into and out of a State Street Fund may harm the Fund's performance by disrupting portfolio management strategies and by increasing expenses. These expenses are borne by all Fund shareholders, including long-term investors who do not generate such costs.

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days in connection with identifying roundtrip transactions. Shareholders with one or more roundtrip transactions may, in the discretion of a State Street Fund, be blocked from making additional purchases or exchanges in any State Street Fund for a period of time. A State Street Fund has discretion to determine that action is not necessary if it determines that a pattern of trading is not abusive or harmful to the affected Fund in a material way. Fund size and/or transaction size may be considered in evaluating any roundtrip transaction.

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;
•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Fund against harmful short-term trading; and
•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Service Options

Dividend and Capital Gain Distribution Option

Please refer to Dividends, Distributions and Tax Considerations below for additional information.

Automatic Withdrawal Plan

Telephone Redemptions and Exchanges

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Automatic Investment Plan

Once the initial investment has been accepted, you may make subsequent investments of $100 or more monthly, quarterly or annually by direct deposit by debiting your bank checking or savings account. Once this option has been established, you may call the State Street Funds to make additional automatic purchases, to change the amount of the existing automatic purchase, or to stop it. The State Street Fund reserves the right to cancel your automatic investment plan if any correspondence sent by the Fund is returned by the postal or other delivery service as “undeliverable.”

Additional Shareholder Information

Account Transfers

Responsibility for Fraud

Right to Change Policies

In addition to the rights expressly stated elsewhere in this Prospectus, the State Street Funds reserve the right, in the future, to:

1.	Alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, service, or privilege at any time;
2.	Accept initial purchases by telephone;
3.	Freeze any account and/or suspend account services if the State Street Funds has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if we reasonably believe a fraudulent transaction may occur or has occurred;
4.	Temporarily freeze any account and/or suspend account services upon initial notification to the State Street Funds of the death of the shareholder until the State Street Funds receive required documentation in good order;
5.	Alter, impose, discontinue, or waive any redemption fee, account service fee, or other fees charged to a group of shareholders; and
6.	Redeem an account or suspend account privileges, without the owner's permission to do so, in cases of threatening conduct or activity the State Street Funds believe to be suspicious, fraudulent, or illegal.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If the Fund's transfer agent identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund).

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Dividends, Distributions and Tax Considerations

Dividends of investment income and capital gain distributions of the Fund will be declared and paid at least annually. Any investment income and capital gains that have not been distributed by December of each calendar year are generally distributed at such time. When the Fund distributes investment income or capital gains, the NAV per share is reduced by the amount of the distribution.

Distribution Options. You can choose from four different distribution options as indicated on the application:

•	Reinvestment Option—Dividends and capital gain distributions will be automatically reinvested in additional shares of the Fund. If you do not indicate a choice on the application, this option will be automatically assigned.
•	Income-Earned Option—Capital gain distributions will be automatically reinvested, but a check, direct deposit or wire will be sent for each dividend distribution.
•	Cash Option—A check, wire or direct deposit will be sent for each dividend and capital gain distribution.
•	Direct Dividends Option—Dividends and capital gain distributions will be automatically invested in another identically registered State Street Fund of the same share class.

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Fund's Prospectus and the annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (800) 647-7327, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Tax Considerations

The following discussion is a summary of some important U.S. federal income tax considerations generally applicable to an investment in the Fund. Your investment in the Fund may have other tax implications. Please consult your tax advisor about federal, state, local, foreign or other tax laws applicable to you. Investors, including non-U.S. investors, may wish to consult the SAI tax section for additional disclosure.

The Fund has elected to be treated as a regulated investment company and intends each year to qualify and to be eligible to be treated as such. A regulated investment company generally is not subject to tax at the corporate level on income and gains that are timely distributed to shareholders. In order to qualify and be eligible for treatment as a regulated investment company, the Fund must, among other things, satisfy diversification, 90% gross income and distribution requirements. The Fund's failure to qualify as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders.

For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Fund owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that the Fund owned (or is deemed to have owned) for more than one year that are properly reported by the Fund as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that the Fund owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income. Distributions of investment income properly reported by the Fund as derived from “qualified dividend income,” which will not include income from the Fund's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by both the shareholder and the Fund. Distributions are taxable to you even if they are paid from income or gains earned by the Fund before your investment (and thus were included in the price you paid for

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your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund, including any capital gain dividends, and net gains recognized on the redemption of Fund Shares.

The Fund's income from or the proceeds of dispositions of its investments in non-U.S. assets may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. In certain instances, the Fund may be entitled to elect to pass through to its shareholders a credit (or deduction, for a shareholder that itemizes deductions and so chooses) for foreign taxes (if any) borne with respect to foreign securities income earned by the Fund. If the Fund so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the Fund. There can be no assurance that the Fund will make such election, even if it is eligible to do so. If the Fund does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes paid by the Fund; in that case the foreign tax will nonetheless reduce the Fund's taxable income. Even if the Fund elects to pass through to shareholders foreign tax credits or deductions, tax-exempt shareholders and those who invest in the Fund through tax-advantaged accounts such as IRAs will not benefit from any such tax credit or deduction. Under certain circumstances, if the Fund receives a refund of foreign taxes paid in respect of a prior year, the value of Fund Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Fund's foreign taxes for the current year could be reduced.

Certain of the Fund's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of the Fund's distributions to shareholders and may require the Fund to sell its investments at a time when it is not advantageous to do so.

If you are not a U.S. person, dividends paid by the Fund that the Fund properly reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends, each as further defined in the SAI, are not subject to withholding of U.S. federal income tax, provided that certain requirements are met. The Fund is permitted, but is not required, to report any part of its dividends as are eligible for such treatment. The Fund's dividends other than those the Fund so reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends generally will be subject to U.S. withholding tax at a 30% rate (or lower applicable treaty rate). See the Fund's SAI for further information.

The U.S. Treasury and Internal Revenue Service (the “IRS”) generally require the Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Code, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the IRS for redemptions of Fund Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Fund and not through a Financial Intermediary, DST Asset Manager Solutions, Inc. will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

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age daily net assets) of 0.25% of the Fund's net assets attributable to its Class A shares. Because these fees are paid out of the assets of the Fund attributable to its Class A shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

The Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of that Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

In addition to payments under the Plan described above, the Fund may reimburse SSGA FD or its affiliates for payments made to Financial Intermediaries that provide certain administrative, recordkeeping, and account maintenance services. The amount of the reimbursement and the manner in which it is calculated are reviewed by the Trustees periodically.

Financial Intermediaries are firms that sell shares of mutual funds, including the Fund, and/or provide certain administrative and account maintenance services to mutual fund investors. Financial Intermediaries may include, among others, brokers, financial planners or advisers, banks, retirement plan recordkeepers and insurance companies.

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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Financial Highlights

The financial highlight tables are intended to help you understand the Fund's financial performance since the Fund's inception. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EMERGING MARKETS EQUITY INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	State Street Emerging Markets Equity Index Fund Class K
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$79.69	$68.70	$59.80	$72.30	$54.10
Income (loss) from investment operations:
Net investment income (loss) (b)	1.65	1.28	2.00	1.60	1.45
Net realized and unrealized gain (loss)	(3.89)	11.18	8.85	(12.30)	18.60
Total from investment operations	(2.24)	12.46	10.85	(10.70)	20.05
Distributions to shareholders from:
Net investment income	(1.48)	(1.47)	(1.95)	(1.35)	(1.50)
Net realized gains	—	—	—	(0.45)	(0.35)
Total distributions	(1.48)	(1.47)	(1.95)	(1.80)	(1.85)
Net asset value, end of period	$75.97	$79.69	$68.70	$59.80	$72.30
Total return (c)	(2.80)%	18.18%	18.13%	(14.77)%	37.19%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$918,212	$879,295	$743,712	$580,430	$607,947
Ratios to Average Net Assets:
Total expenses	0.30%	0.31%	0.33%	0.33%	0.34%
Net expenses	0.17%	0.17%	0.17%	0.17%	0.17%
Net investment income (loss)	2.02%	1.94%	3.10%	2.36%	2.23%
Portfolio turnover rate	11%	13%	13%	7%	6%

(a)	On April 17, 2020, the State Street Emerging Markets Equity Index Fund underwent a 1-for-5 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 11.
(b)	Per share numbers have been calculated using average shares outstanding, which more appropriately presents the per share data for the period.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

The Fund does not consider the U.S. Postal Service or other independent delivery services to be its agents. Therefore, deposits in the mail or with such services, or receipt at the Fund's post office box, of purchase orders or redemption requests, do not constitute receipt by the Fund or Transfer Agent.

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. In the Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (800) 997-7327 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Fund's website at www.ssga.com.

Reports and other information about the Fund are available free of charge on the EDGAR Database on the SEC's Internet site at http://www.sec.gov. Copies of this information also may be obtained, after paying a duplicating fee, by electronic request at the following E-mail address: publicinfo@sec.gov.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITEMCGSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Equity 500 Index Fund: Administrative Shares (STFAX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the State Street Equity 500 Index Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund may offer multiple classes of shares. This Prospectus covers only the Administrative Shares.

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Fund Summary	1
State Street Equity 500 Index Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	7
Additional Information About Non-Principal Investment Strategies and Risks	13
Portfolio Holdings Disclosure	15
Management and Organization	16
Shareholder Information	18
Dividends, Distributions and Tax Considerations	21
Financial Intermediary Arrangements	23
Financial Highlights	25
Index/Trademark Licenses/Disclaimers	27

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State Street Equity 500 Index Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.02%
Distribution and/or Shareholder Service (12b-1) Fees	0.15%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses	0.27%
Less Fee Waivers and/or Expense Reimbursements²	(0.10%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.17%

Other Expenses have been restated to reflect current fees.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.02% of the Fund's or the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

Example:

1 year		3 years		5 years		10 years
$17		$77		$142		$333

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Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). As a shareholder of the Portfolio, the Fund bears its ratable share of the transaction costs associated with the portfolio turnover of the Portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 6% of the average value of its portfolio.

Principal Investment Strategies

Principal Risks

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these risks may result in losses to the Fund. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund may not achieve its investment objective. The Fund is not intended to be a complete investment program, but rather is intended for investment as part of a diversified investment portfolio. Investors should consult their own advisers as to the role of the Fund in their overall investment programs.

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invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's' returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Administrative Shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 20.45% (Q2, 2020)
Lowest Quarterly Return: -19.60% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Ten Years	Inception Date
Administrative Shares				4/18/2001
Return Before Taxes	28.32%	18.17%	16.26%
Return After Taxes on Distributions	27.50%	17.00%	15.46%
Return After Taxes on Distributions and Sale of Fund Shares	17.27%	14.35%	13.55%
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	16.55%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

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Amy Scofield is a Principal of the Adviser and a Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2010.

Purchase and Sale of Fund Shares

Purchase Minimums

To establish an account	$25,000,000
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

State Street Equity 500 Index Fund Administrative Shares

Investment Objective

The Trust's Board of Trustees may change the Fund's investment strategies and other policies without shareholder approval, except as otherwise indicated. The Board of Trustees may change the Fund's investment objective without shareholder approval. If the Trustees were to approve a change to the Equity 500 Index Fund's investment objective, shareholders would receive advance notice.

Principal Investment Strategies

The Fund generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Fund will not invest less than 80% of its total assets in stocks in the Index. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. For this purpose, “total assets” means net assets plus borrowings, if any. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

Consumer Discretionary Sector Risk. The success of consumer product manufacturers and retailers is tied closely to the performance of the overall global economy, interest rates, competition and consumer confidence. Success depends heavily on disposable household income and consumer spending. Also, companies in the consumer discretionary sector may be subject to severe competition, which may have an adverse impact on their respective profitability. Changes in demographics and consumer tastes can also affect the demand for, and success of, consumer products and services in the marketplace.

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Under applicable law or contractual provisions, including if the Fund enters into an investment or transaction with a financial institution and such financial institution (or an affiliate of the financial institution) experiences financial difficulties, then the Fund may in certain situations be prevented or delayed from exercising its rights to terminate the investment or transaction, or to realize on any collateral and may result in the suspension of payment and delivery obligations of the parties under such investment or transactions or in another institution being substituted for that financial institution without the consent of the Fund. Further, the Fund may be subject to “bail-in” risk under applicable law whereby, if required by the financial institution's authority, the financial institution's liabilities could be written down, eliminated or converted into equity or an alternative instrument of ownership. A bail-in of a financial institution may result in a reduction in value of some or all of its securities and, if the Fund holds such securities or has entered into a transaction with such a financial security when a bail-in occurs, the Fund may also be similarly impacted.

Derivatives Risk. A derivative is a financial contract the value of which depends on, or is derived from, the value of an underlying asset, interest rate, or index. Derivative transactions typically involve leverage and may have significant volatility. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. Risks associated with derivative instruments include potential changes in value in response to interest rate changes or other market developments or as a result of the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Adviser anticipated or a different or less favorable effect than the Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that the Fund may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that the Fund will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to the Fund due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

Health Care Sector Risk. Companies in the health care sector are subject to extensive government regulation and their profitability can be significantly affected by restrictions on government reimbursement for medical expenses, rising costs of medical products and services, pricing pressure (including price discounting), limited product lines and an increased emphasis on the delivery of healthcare through outpatient services. Companies in the health care sector are heavily dependent on obtaining and defending patents, which may be time consuming and costly, and the expiration of patents may also adversely affect the profitability of these companies. Health care companies are also subject to extensive litigation based on product liability and similar claims. In addition, their products can become obsolete due to industry innovation, changes in technologies or other market developments. Many new products in the health care sector require significant research and development and may be subject to regulatory approvals, all of which may be time consuming and costly with no guarantee that any product will come to market.

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formance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index (in absolute terms and by comparison with other indices) and, consequently, the performance, volatility, and risk of the Fund. Errors in index data, index computations or the construction of the Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Fund's return may not match the return of the Index for a number of reasons. For example, the return on the sample of securities purchased by the Fund (or the return on securities not included in the Index) to replicate the performance of the Index may not correlate precisely with the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Fund may not be fully invested at times, either as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to track the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Fund's return and that of the Index. Changes in the composition of the Index and regulatory requirements also may impact the Fund's ability to match the return of the Index. The Adviser may apply one or more “screens” or investment techniques to refine or limit the number or types of issuers included in the Index in which the Fund may invest. Application of such screens or techniques may result in investment performance below that of the Index and may not produce results expected by the Adviser. Index tracking risk may be heightened during times of increased market volatility or other unusual market conditions.

Large Shareholder Risk. To the extent a large proportion of the shares of the Portfolio are highly concentrated or held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program. For example, they could require the Portfolio to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to shareholders, or the Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case the Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. The Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

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Fund. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The use of leverage may cause the Fund to liquidate positions when it may not be advantageous to do so to satisfy repayment, interest payment, or margin obligations or to meet asset segregation or coverage requirements.

Liquidity Risk. Liquidity risk is the risk that the Fund may not be able to dispose of investments or close out derivatives transactions readily at a favorable time or prices (or at all) or at prices approximating those at which the Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for the Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. The Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity the Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Fund's investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by the Fund. To the extent the Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

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redemption requests will depend on its ability to redeem its interest in the master fund. The Adviser or an affiliate serves as investment adviser to the master fund, leading to potential conflicts of interest. For example, the Adviser or its affiliates will receive fees based on the amount of assets invested in the master fund. Investment by the Fund in the master fund may be beneficial in the management of the master fund, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest the Fund's assets in a master fund sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in such master fund over a master fund sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by the Fund in a master fund sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a master fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so. The Fund will bear its pro rata portion of the expenses incurred by the master fund.

Unconstrained Sector Risk. The Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. When the Fund focuses its investments in a particular industry or sector, financial, economic, business, and other developments affecting issuers in that industry, market, or economic sector will have a greater effect on the Fund than if it had not focused its assets in that industry, market, or economic sector, which may increase the volatility of the Fund. Any such investment focus may also limit the liquidity of the Fund. In addition, investors may buy or sell substantial amounts of the Fund's shares in response to factors affecting or expected to affect an industry, market, or economic sector in which the Fund focuses its investments, resulting in extreme inflows or outflows of cash into and out of the Fund. Such extreme cash inflows or outflows might affect management of the Fund adversely.

Additional Information About Non-Principal Investment Strategies and Risks

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The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund and the Portfolio) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

The Fund invests as part of a “master/feeder” structure. The Fund currently seeks to achieve its investment objective by investing substantially all of its investable assets in the Portfolio, a separate mutual fund, that has substantially identical investment objective, investment policies, and risks as the Fund. All discussions about the Fund's investment objective, policies and risks should be understood to refer also to the investment objectives, policies and risks of the Portfolio.

The Portfolio's shares are offered exclusively to investors (including without limitation, registered investment companies, private investment pools, bank collective funds, and investment separate accounts) that, like the Fund, pay fees to SSGA FM or its affiliates. The fees paid by those investment vehicles to SSGA FM (or its affiliates) vary depending on a number of factors, including by way of example, the services provided, the risks borne by SSGA FM (or its affiliates), fee rates paid by competitive investment vehicles, and in some cases direct negotiation with investors in the Portfolio.

The Fund can withdraw its investment in the Portfolio if, at any time, the Fund's Board of Trustees determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives of the Portfolio changed so that they were inconsistent with the objectives of the Fund. If the Fund withdraws its investment from the Portfolio, the Fund may invest all of its assets in another mutual fund that has the same investment objective as the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and Portfolio and, subject to the oversight of the Board, is responsible for the investment management of the Fund. The Adviser provides an investment management program for the Fund and manages the investment of the Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the U.S. Securities and Exchange Commission (“SEC”) under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

The Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets, for compensation paid at an annual rate of 0.02% of the Fund's average daily net assets. For the year ended December 31, 2021, the Fund's effective management fee paid was 0.00% of average daily net assets. The Adviser places all orders for purchases and sales of the Portfolio's investments. The Portfolio pays no investment advisory fees to SSGA FM.

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing and sub-transfer agency fees) exceed 0.02% of average daily net assets on an annual basis. This waiver and/or reimbursement arrangement may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees.

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Adviser manages the Fund and the Portfolio using a team of investment professionals. The team approach is used to create an environment that encourages the flow of investment ideas. The portfolio managers within the team work together in a cohesive manner to develop and enhance techniques that drive the investment process for the respective investment strategy. This approach requires portfolio managers to share a variety of responsibilities, including investment strategy and analysis, while retaining responsibility for the implementation of the strategy within any particular portfolio. The approach also enables the team to draw upon the resources of other groups within SSGA. The portfolio management team is overseen by the SSGA Investment Committee.

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The professionals primarily responsible for the day-to-day management of the Equity 500 Index II Portfolio and the Equity 500 Index Fund include the following:

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Fund is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

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The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

Shareholder Information

Determination of Net Asset Value

The Fund determines its net asset value (“NAV”) per share once each business day as of the close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in the Fund. The NAV of the Fund's Administrative Shares is calculated by dividing the value of the assets of the Fund attributable to its Administrative Shares less the liabilities of the Fund attributable to its Administrative Shares by the number of Administrative Shares outstanding. As noted in this Prospectus, the Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when the Fund does not price its shares. Consequently, the NAV of the Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. The Fund values each security or other investment pursuant to guidelines adopted by the Fund's Board of Trustees. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price the Fund would have received had it sold the investment. To the extent that the Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Investing in State Street Institutional Investment Trust Shares

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Purchasing Shares

Investors pay no sales load to invest in the Administrative Shares of the Fund. The price for Fund shares is the NAV per share. Orders received in good form (a purchase order is in good form if it meets the requirements implemented from time to time by the Fund or its Transfer Agent, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) will be priced at the NAV next calculated after the order is accepted by the Fund.

The minimum initial investment in the Administrative Shares is $25 million, although the Adviser may waive the minimum in its discretion. There is no minimum subsequent investment. The Fund intends to be as fully invested as is practicable; therefore, investments must be made either in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank) or securities (“in-kind”) acceptable to the Adviser. Please consult your tax adviser regarding in-kind transactions. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) The Fund reserves the right to cease accepting investments at any time or to reject any purchase order.

In accordance with certain federal regulations, the Trust is required to obtain, verify and record information that identifies each entity that applies to open an account. For this reason, when you open (or change ownership of) an account, the Trust will request certain information, including your name, address and taxpayer identification number, which will be used to verify your identity. If you are unable to provide sufficient information to verify your identity, the Trust will not open an account for you. As required by law, the Trust may employ various procedures, such as comparing your information to fraud databases or requesting additional information and documentation from you, to ensure that the information supplied by you is correct. The Trust reserves the right to reject any purchase order for any reason, including failure to provide the Trust with information necessary to confirm your identity as required by law.

If you are purchasing through a Financial Intermediary, please contact your Financial Intermediary as their requirements may differ.

Redeeming Shares

An investor may redeem all or any portion of its investment at the NAV next determined after it submits a redemption request, in proper form, to the Fund. Regardless of the method the Fund uses to make a redemption payment, the Fund typically expects to pay out redemption proceeds on the next business day after a redemption request is received in good order. If you purchased State Street Fund shares by check or an automatic investment program and you elect to redeem shares within 15 days of the purchase, you may experience delays in receiving redemption proceeds. In this case, the State Street Funds generally will postpone sending redemption proceeds until it can verify that the check or automatic investment program investment has been collected, but in no event will this delay exceed 15 days. There will be no such delay for redemptions following purchases paid by federal funds wire or by bank cashier's check, certified check or treasurer's check. The State Street Funds reserve the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect a Fund. The State Street Funds reserve the right to suspend the right of shareholder redemption or postpone the date of payment for more than seven days to the extent permitted by the 1940 Act.

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The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

If your account is held through an Intermediary, please contact them for additional assistance and advice on how to redeem your shares.

Cost Basis Reporting

Upon the redemption of your shares in the Fund, the Fund or, if you purchase your shares through a Financial Intermediary, your Financial Intermediary, generally will be required to provide you and the Internal Revenue Service (the “IRS”) with cost basis and certain other related tax information about the Fund shares you redeemed. Please contact the Fund or consult your Financial Intermediary, as appropriate, for more information regarding available methods for cost basis reporting and how to select or change a particular method. Please consult your tax advisor to determine which available cost basis method is best for you.

About Mail Transactions

If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location and a Fund's net asset value may change over those days. You might consider using express rather than regular mail if you believe time of receipt of your transaction request to be sensitive.

Frequent-Trading Limits

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;

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•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Funds against harmful short-term trading; and
•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Delivery of Documents to Accounts Sharing an Address

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund).

Dividends, Distributions and Tax Considerations

The Fund invests substantially all of its assets in the Portfolio, which is expected to be treated as a regulated investment company for federal income tax purposes, and so substantially all of the Fund's income will result from distributions or deemed distributions from the Portfolio. Therefore, as applicable, and except as otherwise stated, references in this section to the assets owned or income earned by the Fund will include such assets and income of the Portfolio. The Fund has elected to be treated as a regulated investment company and intends each year to qualify and to be eligible to be

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treated as such. A regulated investment company generally is not subject to tax at the corporate level on income and gains that are timely distributed to shareholders. In order to qualify and be eligible for treatment as a regulated investment company, the Fund must, among other things, satisfy diversification, 90% gross income and distribution requirements. The Fund's failure to qualify and be eligible for treatment as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders.

The Fund generally expects to satisfy the requirements to qualify and be eligible to be treated as a regulated investment company, provided that the Portfolio also meets these requirements; the Fund currently expects that the Portfolio will meet these requirements. Because the Fund will invest substantially all its assets in the Portfolio, if the Portfolio were to fail to satisfy the diversification, 90% gross income, or distribution requirement and were not to cure that failure, the Fund itself would be unable to satisfy the diversification requirement. Such a failure to qualify and be eligible for treatment as a regulated investment company could subject the Fund and/or the Portfolio to regular corporate income taxes.

For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Fund or the Portfolio owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that the Fund or the Portfolio owned (or is deemed to have owned) for more than one year that are properly reported by the Fund, or the Portfolio and the Fund, as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that the Fund or the Portfolio owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income when distributed to you by the Fund. Distributions of investment income properly reported by the Fund, or the Portfolio and the Fund, as derived from “qualified dividend income,” which will not include income from the Fund's or the Portfolio's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by the shareholder, the Fund, and if applicable, the Portfolio. Distributions are taxable to you even if they are paid from income or gains earned by the Fund or the Portfolio before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund, including any capital gain dividends, and net gains recognized on the redemption of Fund Shares.

Certain of the Fund's or the Portfolio's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of the Fund's distributions, or Portfolio's distributions to the Fund, and, in turn, the Fund's distributions to shareholders, and may require the Fund or the Portfolio to sell its investments at a time when it is not advantageous to do so.

The Fund's investments in the Portfolio may cause the tax treatment of the Fund's gains, losses and distributions to differ from the tax treatment that would apply if the Fund invested directly in the types of securities held by the Portfolio. As a result, investors may receive taxable distributions earlier and recognize higher amounts of capital gain or ordinary income than they otherwise would.

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The U.S. Treasury and IRS generally require the Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Internal Revenue Code of 1986, as amended, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the IRS for redemptions of Fund Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Fund and not through a Financial Intermediary, DST Asset Manager Solutions, Inc. will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Fund has adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which the Fund may compensate SSGA FD (or others) for services in connection with the distribution of the Fund's Administrative Shares and for services provided to Fund shareholders (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.15% of the Fund's net assets attributable to its Administrative Shares. Because these fees are paid out of the assets of the Fund attributable to its Administrative Shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

The Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of the Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

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SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as Financial Industry Regulatory Authority, Inc.

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Financial Highlights

The financial highlight tables are intended to help you understand the Fund's Administrative Shares financial performance for the past five fiscal years. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Administrative Shares
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$286.86	$247.00	$196.40	$216.20	$188.30
Income (loss) from investment operations:
Net investment income (loss) (b)	3.57	3.58	3.90	3.40	3.80
Net realized and unrealized gain (loss)	77.70	41.19	57.30	(13.30)	36.60
Total from investment operations	81.27	44.77	61.20	(9.90)	40.40
Distributions to shareholders from:
Net investment income	(4.40)	(4.11)	(4.40)	(3.90)	(4.60)
Net realized gains	(4.95)	(0.80)	(6.20)	(6.00)	(7.90)
Total distributions	(9.35)	(4.91)	(10.60)	(9.90)	(12.50)
Net asset value, end of period	$358.78	$286.86	$247.00	$196.40	$216.20
Total return (c)	28.32%	18.14%	31.14%	(4.56)%	21.43%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$231,075	$246,181	$241,794	$213,270	$274,650
Ratios to Average Net Assets:
Total expenses (d)	0.25%	0.26%	0.27%	0.27%	0.26%
Net expenses (d)	0.17%	0.17%	0.17%	0.17%	0.18%
Net investment income (loss)	1.09%	1.45%	1.68%	1.51%	1.83%
Portfolio turnover rate (e)	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index Fund underwent a 1-for-10 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the State Street Equity 500 Index II Portfolio.
(e)	Portfolio turnover rate is from the State Street Equity 500 Index II Portfolio.

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Index/Trademark Licenses/Disclaimers

The Index Provider is not affiliated with the Trust, the Adviser, the Fund's Administrator, Sub-Administrator, Custodian, Transfer Agent, SSGA FD or any of their respective affiliates. The Adviser (“Licensee”) has entered into license agreements with the Index Providers pursuant to which the Adviser pays a fee to use their respective Indices. The Adviser is sub-licensing rights to the Indices to the Fund at no charge.

S&P Index: The S& P 500^® Index (the “Index”) is a product of S&P Dow Jones Indices LLC or its affiliates (“SPDJI”) and has been licensed for use by the Adviser. S&P^®, Standard & Poor's^®, and S&P 500^® are registered trademarks of Standard & Poor's Financial Services LLC (“S&P”); Dow Jones^® is a registered trademark of Dow Jones Trademark Holdings LLC (“Dow Jones”); and these trademarks have been licensed for use by SPDJI and sub-licensed for certain purposes by the Adviser. It is not possible to invest in an index.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. In a Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (800) 997-7327 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITEQ5ADSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Equity 500 Index Fund: Class R Shares (SSFRX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the State Street Equity 500 Index Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund may offer multiple classes of shares. This Prospectus covers only the Class R Shares.

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Fund Summary	1
State Street Equity 500 Index Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	7
Additional Information About Non-Principal Investment Strategies and Risks	13
Portfolio Holdings Disclosure	15
Management and Organization	16
Shareholder Information	18
Dividends, Distributions and Tax Considerations	21
Financial Intermediary Arrangements	23
Financial Highlights	25
Index/Trademark Licenses/Disclaimers	27

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State Street Equity 500 Index Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.02%
Distribution and/or Shareholder Service (12b-1) Fees	0.60%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses	0.72%
Less Fee Waivers and/or Expense Reimbursements²	(0.10%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.62%

Other Expenses have been restated to reflect current fees.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.02% of the Fund's or the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

Example:

1 year		3 years		5 years		10 years
$63		$220		$391		$885

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Portfolio Turnover:

Principal Investment Strategies

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's' returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Class R Shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 20.34% (Q2, 2020)
Lowest Quarterly Return: -19.69% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Ten Years	Inception Date
Class R Shares				6/7/2005
Return Before Taxes	27.74%	17.65%	15.73%
Return After Taxes on Distributions	27.08%	16.63%	15.06%
Return After Taxes on Distributions and Sale of Fund Shares	16.85%	13.97%	13.13%
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	16.55%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

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Amy Scofield is a Principal of the Adviser and a Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2010.

Purchase and Sale of Fund Shares

Purchase Minimums

To establish an account	$25,000,000
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

State Street Equity 500 Index Fund Class R

Investment Objective

Principal Investment Strategies

The Fund generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Fund will not invest less than 80% of its total assets in stocks in the Index. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. For this purpose, “total assets” means net assets plus borrowings, if any. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

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Derivatives Risk. A derivative is a financial contract the value of which depends on, or is derived from, the value of an underlying asset, interest rate, or index. Derivative transactions typically involve leverage and may have significant volatility. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. Risks associated with derivative instruments include potential changes in value in response to interest rate changes or other market developments or as a result of the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Adviser anticipated or a different or less favorable effect than the Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that the Fund may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that the Fund will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to the Fund due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

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Liquidity Risk. Liquidity risk is the risk that the Fund may not be able to dispose of investments or close out derivatives transactions readily at a favorable time or prices (or at all) or at prices approximating those at which the Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for the Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. The Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity the Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

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Unconstrained Sector Risk. The Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. When the Fund focuses its investments in a particular industry or sector, financial, economic, business, and other developments affecting issuers in that industry, market, or economic sector will have a greater effect on the Fund than if it had not focused its assets in that industry, market, or economic sector, which may increase the volatility of the Fund. Any such investment focus may also limit the liquidity of the Fund. In addition, investors may buy or sell substantial amounts of the Fund's shares in response to factors affecting or expected to affect an industry, market, or economic sector in which the Fund focuses its investments, resulting in extreme inflows or outflows of cash into and out of the Fund. Such extreme cash inflows or outflows might affect management of the Fund adversely.

Additional Information About Non-Principal Investment Strategies and Risks

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The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund and the Portfolio) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing and sub-transfer agency fees) exceed 0.02% of average daily net assets on an annual basis. This waiver and/or reimbursement arrangement may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees.

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

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The professionals primarily responsible for the day-to-day management of the Equity 500 Index II Portfolio and the Equity 500 Index Fund include the following:

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Fund is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

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The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

Shareholder Information

Determination of Net Asset Value

The Fund determines its net asset value (“NAV”) per share once each business day as of the close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in the Fund. The NAV of the Fund's Class R Shares is calculated by dividing the value of the assets of the Fund attributable to its Class R Shares less the liabilities of the Fund attributable to its Class R Shares by the number of Class R Shares outstanding. As noted in this Prospectus, the Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when the Fund does not price its shares. Consequently, the NAV of the Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. The Fund values each security or other investment pursuant to guidelines adopted by the Fund's Board of Trustees. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price the Fund would have received had it sold the investment. To the extent that the Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Investing in State Street Institutional Investment Trust Shares

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Purchasing Shares

Investors pay no sales load to invest in the Class R Shares of the Fund. The price for Fund shares is the NAV per share. Orders received in good form (a purchase order is in good form if it meets the requirements implemented from time to time by the Fund or its Transfer Agent, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) will be priced at the NAV next calculated after the order is accepted by the Fund.

The minimum initial investment in the Class R Shares is $25 million, although the Adviser may waive the minimum in its discretion. There is no minimum subsequent investment. The Fund intends to be as fully invested as is practicable; therefore, investments must be made either in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank) or securities (“in-kind”) acceptable to the Adviser. Please consult your tax adviser regarding in-kind transactions. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) The Fund reserves the right to cease accepting investments at any time or to reject any purchase order.

If you are purchasing through a Financial Intermediary, please contact your Financial Intermediary as their requirements may differ.

Redeeming Shares

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The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

If your account is held through an Intermediary, please contact them for additional assistance and advice on how to redeem your shares.

Cost Basis Reporting

About Mail Transactions

Frequent-Trading Limits

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;

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•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Funds against harmful short-term trading; and
•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Delivery of Documents to Accounts Sharing an Address

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund).

Dividends, Distributions and Tax Considerations

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For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Fund or the Portfolio owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that the Fund or the Portfolio owned (or is deemed to have owned) for more than one year that are properly reported by the Fund, or the Portfolio and the Fund, as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that the Fund or the Portfolio owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income when distributed to you by the Fund. Distributions of investment income properly reported by the Fund, or the Portfolio and the Fund, as derived from “qualified dividend income,” which will not include income from the Fund's or the Portfolio's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by the shareholder, the Fund, and if applicable, the Portfolio. Distributions are taxable to you even if they are paid from income or gains earned by the Fund or the Portfolio before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund, including any capital gain dividends, and net gains recognized on the redemption of Fund Shares.

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Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the IRS for redemptions of Fund Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Fund and not through a Financial Intermediary, DST Asset Manager Solutions, Inc. will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Fund has adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which the Fund may compensate SSGA FD (or others) for services in connection with the distribution of the Fund's Class R Shares and for services provided to Fund shareholders (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.60% of the Fund's net assets attributable to its Class R Shares. Because these fees are paid out of the assets of the Fund attributable to its Class R Shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

The Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of the Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

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SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as Financial Industry Regulatory Authority, Inc.

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Financial Highlights

The financial highlight tables are intended to help you understand the Class R Shares financial performance for the past five fiscal years. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class R Shares
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$286.68	$246.80	$196.20	$216.10	$188.10
Income (loss) from investment operations:
Net investment income (loss) (b)	2.52	2.41	2.90	2.40	2.90
Net realized and unrealized gain (loss)	77.04	41.07	57.10	(13.30)	36.60
Total from investment operations	79.56	43.48	60.00	(10.90)	39.50
Distributions to shareholders from:
Net investment income	(2.73)	(2.80)	(3.20)	(3.00)	(3.60)
Net realized gains	(4.95)	(0.80)	(6.20)	(6.00)	(7.90)
Total distributions	(7.68)	(3.60)	(9.40)	(9.00)	(11.50)
Net asset value, end of period	$358.56	$286.68	$246.80	$196.20	$216.10
Total return (c)	27.74%	17.63%	30.58%	(5.04)%	20.96%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$39,359	$35,839	$37,222	$32,099	$42,249
Ratios to Average Net Assets:
Total expenses (d)	0.70%	0.71%	0.72%	0.72%	0.71%
Net expenses (d)	0.62%	0.62%	0.62%	0.62%	0.63%
Net investment income (loss)	0.78%	0.98%	1.27%	1.06%	1.41%
Portfolio turnover rate (e)	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index Fund underwent a 1-for-10 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the State Street Equity 500 Index II Portfolio.
(e)	Portfolio turnover rate is from the State Street Equity 500 Index II Portfolio.

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Index/Trademark Licenses/Disclaimers

S&P Index: The S& P 500^® Index (the “Index”) is a product of S&P Dow Jones Indices LLC or its affiliates (“SPDJI”) and has been licensed for use by the Adviser. S&P^®, Standard & Poor's^®, and S&P 500^® are registered trademarks of Standard & Poor's Financial Services LLC (“S&P”); Dow Jones^® is a registered trademark of Dow Jones Trademark Holdings LLC (“Dow Jones”); and these trademarks have been licensed for use by SPDJI and sub-licensed for certain purposes by the Adviser. It is not possible to invest in an index.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. In a Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (800) 997-7327 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITCLRSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Equity 500 Index Fund: Service Shares (STBIX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the State Street Equity 500 Index Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund may offer multiple classes of shares. This Prospectus covers only the Service Shares.

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Fund Summary	1
State Street Equity 500 Index Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	7
Additional Information About Non-Principal Investment Strategies and Risks	13
Portfolio Holdings Disclosure	15
Management and Organization	16
Shareholder Information	18
Dividends, Distributions and Tax Considerations	21
Financial Intermediary Arrangements	23
Financial Highlights	25
Index/Trademark Licenses/Disclaimers	27

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State Street Equity 500 Index Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.02%
Distribution and/or Shareholder Service (12b-1) Fees	0.25%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses	0.37%
Less Fee Waivers and/or Expense Reimbursements²	(0.10%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.27%

Other Expenses have been restated to reflect current fees.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.02% of the Fund's or the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

Example:

1 year		3 years		5 years		10 years
$28		$109		$198		$458

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Portfolio Turnover:

Principal Investment Strategies

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's' returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Service Shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 20.46% (Q2, 2020)
Lowest Quarterly Return: -19.62% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Ten Years	Inception Date
Service Shares				3/10/2003
Return Before Taxes	28.19%	18.05%	16.15%
Return After Taxes on Distributions	27.41%	16.92%	15.38%
Return After Taxes on Distributions and Sale of Fund Shares	17.18%	14.27%	13.46%
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	16.55%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

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Amy Scofield is a Principal of the Adviser and a Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2010.

Purchase and Sale of Fund Shares

Purchase Minimums

To establish an account	$25,000,000
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

State Street Equity 500 Index Fund Service Shares

Investment Objective

Principal Investment Strategies

The Fund generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Fund may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Fund may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Fund will not invest less than 80% of its total assets in stocks in the Index. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. For this purpose, “total assets” means net assets plus borrowings, if any. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

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Derivatives Risk. A derivative is a financial contract the value of which depends on, or is derived from, the value of an underlying asset, interest rate, or index. Derivative transactions typically involve leverage and may have significant volatility. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. Risks associated with derivative instruments include potential changes in value in response to interest rate changes or other market developments or as a result of the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Adviser anticipated or a different or less favorable effect than the Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that the Fund may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that the Fund will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to the Fund due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

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Liquidity Risk. Liquidity risk is the risk that the Fund may not be able to dispose of investments or close out derivatives transactions readily at a favorable time or prices (or at all) or at prices approximating those at which the Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for the Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. The Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity the Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

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Unconstrained Sector Risk. The Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. When the Fund focuses its investments in a particular industry or sector, financial, economic, business, and other developments affecting issuers in that industry, market, or economic sector will have a greater effect on the Fund than if it had not focused its assets in that industry, market, or economic sector, which may increase the volatility of the Fund. Any such investment focus may also limit the liquidity of the Fund. In addition, investors may buy or sell substantial amounts of the Fund's shares in response to factors affecting or expected to affect an industry, market, or economic sector in which the Fund focuses its investments, resulting in extreme inflows or outflows of cash into and out of the Fund. Such extreme cash inflows or outflows might affect management of the Fund adversely.

Additional Information About Non-Principal Investment Strategies and Risks

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The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund and the Portfolio) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing and sub-transfer agency fees) exceed 0.02% of average daily net assets on an annual basis. This waiver and/or reimbursement arrangement may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees.

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

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The professionals primarily responsible for the day-to-day management of the Equity 500 Index II Portfolio and the Equity 500 Index Fund include the following:

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Fund is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

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The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

Shareholder Information

Determination of Net Asset Value

The Fund determines its net asset value (“NAV”) per share once each business day as of the close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in the Fund. The NAV of the Fund's Service Shares is calculated by dividing the value of the assets of the Fund attributable to its Service Shares less the liabilities of the Fund attributable to its Service Shares by the number of Service Shares outstanding. As noted in this Prospectus, the Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when the Fund does not price its shares. Consequently, the NAV of the Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. The Fund values each security or other investment pursuant to guidelines adopted by the Fund's Board of Trustees. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price the Fund would have received had it sold the investment. To the extent that the Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Investing in State Street Institutional Investment Trust Shares

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Purchasing Shares

Investors pay no sales load to invest in the Service Shares of the Fund. The price for Fund shares is the NAV per share. Orders received in good form (a purchase order is in good form if it meets the requirements implemented from time to time by the Fund or its Transfer Agent, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) will be priced at the NAV next calculated after the order is accepted by the Fund.

The minimum initial investment in the Service Shares is $25 million, although the Adviser may waive the minimum in its discretion. There is no minimum subsequent investment. The Fund intends to be as fully invested as is practicable; therefore, investments must be made either in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank) or securities (“in-kind”) acceptable to the Adviser. Please consult your tax adviser regarding in-kind transactions. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) The Fund reserves the right to cease accepting investments at any time or to reject any purchase order.

If you are purchasing through a Financial Intermediary, please contact your Financial Intermediary as their requirements may differ.

Redeeming Shares

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The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

If your account is held through an Intermediary, please contact them for additional assistance and advice on how to redeem your shares.

Cost Basis Reporting

About Mail Transactions

Frequent-Trading Limits

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;

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•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Funds against harmful short-term trading; and
•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Delivery of Documents to Accounts Sharing an Address

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

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For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Fund or the Portfolio owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that the Fund or the Portfolio owned (or is deemed to have owned) for more than one year that are properly reported by the Fund, or the Portfolio and the Fund, as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that the Fund or the Portfolio owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income when distributed to you by the Fund. Distributions of investment income properly reported by the Fund, or the Portfolio and the Fund, as derived from “qualified dividend income,” which will not include income from the Fund's or the Portfolio's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by the shareholder, the Fund, and if applicable, the Portfolio. Distributions are taxable to you even if they are paid from income or gains earned by the Fund or the Portfolio before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund, including any capital gain dividends, and net gains recognized on the redemption of Fund Shares.

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Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the IRS for redemptions of Fund Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Fund and not through a Financial Intermediary, DST Asset Manager Solutions, Inc. will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Fund has adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which the Fund may compensate SSGA FD (or others) for services in connection with the distribution of the Fund's Service Shares and for services provided to Fund shareholders (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.25% of the Fund's net assets attributable to its Service Shares. Because these fees are paid out of the assets of the Fund attributable to its Service Shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

The Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of the Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

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SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as Financial Industry Regulatory Authority, Inc.

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Financial Highlights

The financial highlight tables are intended to help you understand the Fund's Service Shares financial performance for the past five fiscal years. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Service Shares
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$286.59	$246.70	$196.20	$216.00	$188.10
Income (loss) from investment operations:
Net investment income (loss) (b)	0.94	3.33	3.10	3.20	1.50
Net realized and unrealized gain (loss)	79.89	41.18	57.70	(13.30)	38.70
Total from investment operations	80.83	44.51	60.80	(10.10)	40.20
Distributions to shareholders from:
Net investment income	(4.03)	(3.82)	(4.10)	(3.70)	(4.40)
Net realized gains	(4.95)	(0.80)	(6.20)	(6.00)	(7.90)
Total distributions	(8.98)	(4.62)	(10.30)	(9.70)	(12.30)
Net asset value, end of period	$358.44	$286.59	$246.70	$196.20	$216.00
Total return (c)	28.19%	18.06%	30.99%	(4.66)%	21.33%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$8,134	$22,997	$20,457	$20,897	$27,876
Ratios to Average Net Assets:
Total expenses (d)	0.35%	0.36%	0.37%	0.37%	0.36%
Net expenses (d)	0.27%	0.27%	0.27%	0.27%	0.28%
Net investment income (loss)	0.29%	1.35%	1.36%	1.44%	0.73%
Portfolio turnover rate (e)	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index Fund underwent a 1-for-10 reverse share split. The per share data presented here have been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Ratio does not include the expenses of the State Street Equity 500 Index II Portfolio.
(e)	Portfolio turnover rate is from the State Street Equity 500 Index II Portfolio.

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Index/Trademark Licenses/Disclaimers

S&P Index: The S& P 500^® Index (the “Index”) is a product of S&P Dow Jones Indices LLC or its affiliates (“SPDJI”) and has been licensed for use by the Adviser. S&P^®, Standard & Poor's^®, and S&P 500^® are registered trademarks of Standard & Poor's Financial Services LLC (“S&P”); Dow Jones^® is a registered trademark of Dow Jones Trademark Holdings LLC (“Dow Jones”); and these trademarks have been licensed for use by SPDJI and sub-licensed for certain purposes by the Adviser. It is not possible to invest in an index.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. In a Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (800) 997-7327 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITSERVSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street ESG Liquid Reserves Fund

Institutional Class (ELFXX) Administration Class (ESBXX) Investment Class (ELGXX) Investor Class (ENVXX) Premier Class (ELRXX) Opportunity Class (OPEXX)

State Street Institutional Liquid Reserves Fund

Institutional Class (SSHXX) Administration Class (SSYXX) Investment Class (SSVXX) Investor Class (SSZXX) Premier Class (SSIXX) Opportunity Class (OPIXX)

State Street Institutional Treasury Money Market Fund

Institutional Class (SSJXX) Administration Class (SSKXX) Investment Class (TRVXX) Investor Class (SSNXX) Premier Class (TRIXX) Opportunity Class (OPRXX)

State Street Institutional Treasury Plus Money Market Fund

Institutional Class (SAJXX) Administration Class (SSQXX) Investment Class (TPVXX) Investor Class (SAEXX) Premier Class (TPIXX) Opportunity Class (OPTXX)

State Street Institutional U.S. Government Money Market Fund

Institutional Class (SAHXX) Administration Class (SALXX) Investment Class (GVVXX) Investor Class (SAMXX) Premier Class (GVMXX) Opportunity Class (OPGXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Institutional Class, Administration Class, Investment Class, Investor Class, Premier Class and Opportunity Class Shares of the applicable Funds.

State Street ESG Liquid Reserves Fund and State Street Institutional Liquid Reserves Fund are “floating net asset value” money market funds. The share price of these Funds will fluctuate.

None of State Street Corporation, State Street Bank and Trust Company, State Street Global Advisors, SSGA Funds Management, Inc. or their affiliates (“State Street Entities”) guarantee the value of your investment at $1.00 per share or any other target share price. Investors should have no expectation of capital support to the Funds from State Street Entities.

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Fund Summaries	1
State Street ESG Liquid Reserves Fund	1
State Street Institutional Liquid Reserves Fund	10
State Street Institutional Treasury Money Market Fund	17
State Street Institutional Treasury Plus Money Market Fund	23
State Street Institutional U.S. Government Money Market Fund	29
Additional Information About Investment Objectives, Principal Strategies and Risks	36
Additional Information About Non-Principal Investment Strategies and Risks	48
Portfolio Holdings Disclosure	50
Management and Organization	51
Shareholder Information	53
Dividends, Distributions and Tax Considerations	61
Financial Intermediary Arrangements	62
Financial Highlights	65

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State Street ESG Liquid Reserves Fund

Investment Objective

The investment objective of the State Street ESG Liquid Reserves Fund (the “ESG Liquid Reserves Fund” or sometimes referred to in context as the “Fund”) is to seek to maximize current income while giving consideration to SSGA Funds Management, Inc.'s (“SSGA FM's” or the “Adviser's”) environmental, social and governance (“ESG”) criteria, to the extent consistent with the preservation of capital and liquidity, by investing in U.S. dollar-denominated money market securities.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the ESG Liquid Reserves Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. The expenses shown in the table and the Example reflect the expenses of the Fund and the Fund's proportionate share of the expenses of the State Street ESG Liquid Reserves Portfolio (the “ESG Liquid Reserves Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Management Fee	0.05%	0.05%	0.05%	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.05%	0.10%	0.00%	0.00%	0.00%
Other Expenses¹	0.13%	0.30%	0.35%	0.18%	0.10%	0.13%
Total Annual Fund Operating Expenses	0.18%	0.40%	0.50%	0.23%	0.15%	0.18%
Less Fee Waivers and/or Expense Reimbursements²	(0.03%)	(0.03%)	(0.03%)	(0.03%)	(0.03%)	(0.03%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.15%	0.37%	0.47%	0.20%	0.12%	0.15%

Other Expenses for the Opportunity Class, Administration Class, and Investment Class shares are based on estimates for the current fiscal year.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”) is contractually obligated, through April 30, 2023 (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.07% of average daily net assets on an annual basis (the “Total Annual Fund Operating Expense Waiver”). The Total Annual Fund Operating Expense Waiver may not be terminated prior to April 30, 2023 with respect to the Fund except with approval of the Fund's Board of Trustees. The Adviser and its affiliates, may voluntarily reduce all or a portion of their fees and/or reimburse expenses of the Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”), or a yield below a specified level, which may vary from time to time in the Adviser's sole discretion. The Fund has agreed, subject to certain limitations, to reimburse the Adviser and its affiliates for the full dollar amount of any Voluntary Reduction incurred beginning on May 1, 2020. During the fiscal year ended December 31, 2021, the Adviser and its affiliates did not waive fees or reimbursed expenses under the Voluntary Reduction.

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Each of the Adviser and its affiliates may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund. Any future reimbursement by the Fund of the Voluntary Reduction would increase the Fund's expenses and may reduce the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield.

Example:

	1 year	3 years	5 years	10 years
Institutional	$15	$55	$98	$227
Administration	$38	$125	$221	$502
Investment	$48	$157	$277	$625
Investor	$20	$71	$126	$290
Premier	$12	$45	$82	$189
Opportunity	$15	$55	$98	$227

Principal Investment Strategies

The ESG Liquid Reserves Fund follows a disciplined investment process in which the Adviser bases its decisions on the relative attractiveness of different money market instruments while considering ESG criteria at the time of purchase. Among other things, the Adviser conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team.

The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. In the Adviser's opinion, the attractiveness of an instrument may vary depending on, among other things, the general level of interest rates and imbalances of supply and demand in the market.

Although the Fund is a money market fund, the net asset value (“NAV”) of the Fund's Shares “floats,” fluctuating with changes in the values of the Fund's portfolio securities. The Fund typically accepts purchase and redemption orders multiple times per day, and calculates its NAV at each such time.

The Adviser intends to consider ESG criteria at the time of purchase by using an ESG-related metric for each Fund investment. For most Fund investments, the Adviser uses a proprietary scoring system developed by SSGA that assigns an ESG rating, in the form of a “Responsibility” or “R-Factor^TM” score, to the issuer. The amount of the Fund's investments assigned an R-Factor^TM score will vary from time to time and can change significantly. The R-Factor^TM score measures the performance of a company's business operations and governance as related to financially material ESG challenges facing the issuer's industry. The R-Factor^TM score for each applicable issuer draws on a number of data sources, including third-party data providers, that provide metrics on a variety of ESG topics.

The R-Factor^TM scoring process comprises two underlying components. The first component is based on the framework published by the Sustainability Accounting Standards Board (“SASB”), which is used for all ESG aspects of the score other than those relating to corporate governance issues. The SASB framework attempts to identify ESG risks that are financially material to the issuer based on its industry classification. This component of the R-Factor^TM score is determined using only those metrics from the data sources that specifically address ESG risks identified by the SASB framework as being financially material to the issuer based on its industry classification.

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The second component of the score is generated using region-specific corporate governance codes developed by investors or regulators. The governance codes describe minimum corporate governance expectations of a particular region and typically address topics such as shareholder rights, board independence and executive compensation. The R-Factor^TM scoring process uses data provided by a corporate governance data and analytics provider to assign a governance score to issuers according to these governance codes.

For an issuer that receives an R-Factor^TM score, the Fund generally will not take into account the practices or the record of the issuer in respect of ESG factors other than those (i) identified as being financially material to the issuer based on its industry classification under the SASB framework or (ii) applicable to the issuer under local governance codes. Not all criteria are assigned equal weight in constructing an R-Factor^TM score.

R-Factor^TM scores are not used for investments in U.S. government securities, securities of governments other than the U.S. government, or securities of issuers for which ESG data sufficient to generate an R-Factor^TM score is not available. In the case of issuers for which R-Factor^TM scores are not used, security selection is based on the Adviser's fundamental security selection process, which may include the application of alternative ESG ratings from a data source to determine whether the issuer of a security meets a particular ESG criteria set by the Adviser.

In making investment decisions, the Adviser will normally consider ESG factors at the time of investment. Once a security is purchased by the Fund, the Adviser will periodically review an issuer's ESG score to determine how it compares to the Fund's ESG criteria and affects the Fund's overall ESG orientation, but the Adviser typically will not sell a security based solely on a change in the Adviser's ESG evaluation of an issuer. When determining whether to sell a security, the Adviser considers, among other things, current and anticipated changes in interest rates, current valuation relative to alternatives in the market, general market conditions and any other factors deemed relevant by the Adviser.

The Adviser will select securities for investment by the Fund based on its consideration of fundamental and technical factors relating to the investment, as well as in some cases seeking to increase R-Factor^TM scoring of the overall investment portfolio. The portfolio construction process begins with an analysis of fundamental factors relating to a potential investment, after which the Adviser conducts its ESG analysis, as described above. Final investment decisions are made by the portfolio managers typically on the basis of market conditions as well as technical and ESG considerations with respect to both specific instruments and the overall composition of the portfolio. The Adviser's ESG analysis is an integral component of portfolio construction. An issuer in which the Fund invests may rank higher or lower across ESG factors or in any one factor as compared with other issuers in which the Fund invests or might invest. For example, it is possible that the Adviser might select for investment the securities of an issuer with a lower R-Factor^TM score than another on the basis of the relative yield of that issuer's securities. Conversely, it is possible that the Adviser might select for investment the securities of an issuer with a higher R-Factor^TM score and lower yield than another to achieve a higher overall R-Factor^TM score for the investment portfolio. The Fund does not expect typically to invest in securities of issuers that do not achieve a minimum R-Factor^TM threshold score set by the Adviser from time to time (except that certain issuers, as noted above, do not receive R-Factor^TM scores). There may be certain investments with desirable investment attributes that the Adviser will not consider for investment by the Fund because they do not meet that threshold, and the Fund might achieve less favorable investment results than a comparable fund that is not so limited.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including European Certificates of Deposit (“ECDs”), European Time Deposits (“ETDs”) and Yankee Certificates of Deposit (“YCDs”)), commercial paper and other high quality obligations of U.S. or foreign companies, including “green” bonds; secured securities such as asset-backed commercial paper; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

ECDs are U.S. dollar-denominated certificates of deposit issued by a bank outside of the United States. ETDs are U.S. dollar-denominated deposits in foreign branches of U.S. banks and foreign banks. YCDs are U.S. dollar-denominated certificates of deposit issued by U.S. branches of foreign banks. These instruments have different risks than those associated with the obligations of U.S. banks operating in the United States.

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The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the ESG Liquid Reserves Portfolio, a separate series of State Street Master Funds (the “Portfolio”), which has substantially identical investment policies to the Fund. When a Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio, and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

Principal Risks

The Fund is subject to the following principal risks. You could lose money by investing in the Fund. Because the share price of the Fund will fluctuate, when you sell your shares, they may be worth more or less than what you originally paid for them. The Fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares if the Fund's liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

Money Market Risk-Floating NAV: The Fund does not maintain a constant net asset value per share. The value of the Fund's shares is calculated to four decimal places and will vary reflecting the value of the portfolio of investments held by the Fund. It is possible to lose money by investing in the Fund.

ESG Investing Risk: The Fund's incorporation of ESG considerations in its investment process may cause it to make different investments than funds that have a similar investment universe and/or investment style but that do not incorporate such considerations in their strategy or investment processes. Under certain economic conditions, this could cause the Fund's investment performance to be worse than similar funds that do not incorporate such considerations in their investment strategies or processes. In applying ESG criteria to its investment decisions, the Fund may forgo higher yielding investments that it would invest in absent the application of its ESG investing criteria. In addition, due to constraints imposed by regulations applicable to money market funds or other considerations relating to credit quality, liquidity or yield, the Fund may be unable to successfully implement its ESG investment strategy. The Fund will seek to identify companies that it believes meet its ESG criteria based on the data provided by third parties. The data provided by third parties may be incomplete, inaccurate or unavailable, which could cause the Adviser to incorrectly assess a company's ESG practices. The Fund may invest in companies that do not reflect the beliefs and values of any particular investor.

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Interest Rate Risk: Interest rate risk is the risk that debt securities will decline in value because of increases in interest rates. The value of a security with a longer duration will be more sensitive to changes in interest rates than a similar security with a shorter duration. Interest-only and principal-only securities are especially sensitive to interest rate changes, which can affect not only their prices but can also change the income flows and repayment assumptions about those investments.

Repurchase Agreement Risk: Repurchase agreements may be viewed as loans made by the Fund which are collateralized by the securities subject to repurchase. If the Fund's counterparty should default on its obligations and the Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, the Fund may realize a loss.

Banking Companies Risk: The performance of bank stocks may be affected by extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, and the interest rates and fees they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds, and can fluctuate significantly when interest rates change. Credit losses resulting from financial difficulties of borrowers can negatively impact banking companies. Banks may also be subject to severe price competition. Competition is high among banking companies and failure to maintain or increase market share may result in lost market value.

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it may lose money on an operating basis). It is possible that the Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income.

Counterparty Risk: The Fund will be subject to credit risk with respect to the counterparties with which the Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, the Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Large Shareholder Risk: To the extent a large proportion of the interests of the Portfolio are held by a small number of investors (or a single investor), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these investors will purchase or redeem Portfolio interests in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program.

Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

Rapid Changes in Interest Rates Risk: Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause the Fund to sell portfolio securities at a loss to satisfy those requests.

Restricted Securities Risk: The Fund may hold securities that have not been registered for sale to the public under the U.S. federal securities laws. There can be no assurance that a trading market will exist at any time for any particular restricted security. Limitations on the resale of these securities may have an adverse effect on their marketability, and may prevent the Fund from disposing of them promptly at reasonable prices. The Fund may have to bear the expense of registering the securities for resale and the risk of substantial delays in effecting the registration. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

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Risks Related to ECDs, ETDs and YCDs: Banks issuing ECDs, ETDs and YCDs are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of foreign issuers also involve risks such as future unfavorable political and economic developments, withholding or other tax, seizures of foreign deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

Variable and Floating Rate Securities Risk: During periods of increasing interest rates, changes in the coupon rates of variable or floating rate securities may lag behind the changes in market rates or may have limits on the maximum increases in coupon rates. Alternatively, during periods of declining interest rates, the coupon rates on such securities will typically readjust downward resulting in a lower yield.

Zero-Coupon Bond Risk: Zero-coupon bonds usually trade at a deep discount from their face or par values and are subject to greater market value fluctuations from changing interest rates than debt obligations of comparable maturities that make current distributions of interest.

Performance

The bar chart and table below provide some indication of the risks of investing in the ESG Liquid Reserves Fund by illustrating the variability of the Fund's returns from year-to-year. The bar chart shows how the Investor class shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.27% (Q2, 2020)
Lowest Quarterly Return: 0.01% (Q4, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Since Inception	Inception Date
Investor Class	0.01%	0.28%	12/19/2019
Institutional Class	0.04%	0.32%	12/19/2019
Premier Class	0.07%	0.39%	12/3/2019

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

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Purchase and Sale of Fund Shares

Purchase Minimums

Institutional Class
To establish an account	$25,000,000
To add to an existing account	No minimum
Administration Class
To establish an account	$1,000
To add to an existing account	No minimum
Investment Class
To establish an account	$250
To add to an existing account	No minimum
Investor Class
To establish an account	$10,000,000
To add to an existing account	No minimum
Premier Class
To establish an account	$250,000,000
To add to an existing account	No minimum
Opportunity Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

For wire transfer instructions, please call (866) 392-0869 between 7:00 a.m. and 5:00 p.m. Eastern time. Redemptions by telephone are permitted only if you previously have been authorized for these transactions.

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

For U.S. federal income tax purposes, the Fund's distributions are generally taxed as ordinary income unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or individual retirement account. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

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Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Liquid Reserves Fund

Investment Objective

The investment objective of the State Street Institutional Liquid Reserves Fund (the “ILR Fund” or sometimes referred to in context as the “Fund”) is to seek to maximize current income, to the extent consistent with the preservation of capital and liquidity, by investing in U.S. dollar-denominated money market securities.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the ILR Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. The expenses shown in the table and the Example reflect the expenses of the Fund and the Fund's proportionate share of the expenses of the State Street Money Market Portfolio (the “Money Market Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Management Fee	0.05%	0.05%	0.05%	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.05%	0.10%	0.00%	0.00%	0.00%
Other Expenses	0.10%	0.27%	0.32%	0.15%	0.07%	0.10%¹
Total Annual Fund Operating Expenses²	0.15%	0.37%	0.47%	0.20%	0.12%	0.15%

Other Expenses for the Opportunity Class shares are based on estimates for the current fiscal year.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”) and its affiliates, may voluntarily reduce all or a portion of their fees and/or reimburse expenses of the Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”), or a yield below a specified level, which may vary from time to time in the Adviser's sole discretion. The Fund has agreed, subject to certain limitations, to reimburse the Adviser and its affiliates for the full dollar amount of any Voluntary Reduction incurred beginning on May 1, 2020. During the fiscal year ended December 31, 2021, the Adviser and its affiliates waived fees and/or reimbursed expenses under the Voluntary Reduction. Each of the Adviser and its affiliates may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund. Any future reimbursement by the Fund of the Voluntary Reduction would increase the Fund's expenses and may reduce the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield.

Example:

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	1 year	3 years	5 years	10 years
Institutional	$15	$48	$85	$192
Administration	$38	$119	$208	$468
Investment	$48	$151	$263	$591
Investor	$20	$64	$113	$255
Premier	$12	$39	$68	$154
Opportunity	$15	$48	$85	$192

Principal Investment Strategies

The ILR Fund follows a disciplined investment process in which SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, bases its decisions on the relative attractiveness of different money market instruments. In the Adviser's opinion, the attractiveness of an instrument may vary depending on the general level of interest rates, as well as imbalances of supply and demand in the market. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

European Certificates of Deposit (“ECDs”) are U.S. dollar-denominated certificates of deposit issued by a bank outside of the United States. European Time Deposits (“ETDs”) are U.S. dollar-denominated deposits in foreign branches of U.S. banks and foreign banks. Yankee Certificates of Deposit (“YCDs”) are U.S. dollar-denominated certificates of deposit issued by U.S. branches of foreign banks. These instruments have different risks than those associated with the obligations of U.S. banks operating in the United States.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Money Market Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio, and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

Principal Risks

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insured or guaranteed by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

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are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury, are not supported by the full faith and credit of the U.S. government, and involve increased credit risks.

Low Short-Term Interest Rates: During market conditions in which short-term interest rates are at low levels, the Fund's yield can be very low. During these conditions, it is possible that the Fund will generate an insufficient amount of income to pay its expenses, and that it will not be able to pay a daily dividend and may have a negative yield (i.e., it may lose money on an operating basis). It is possible that the Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income.

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by the master fund. Substantial redemptions by other investors in a master fund may affect the master fund's investment program adversely and limit the ability of the master fund to achieve its objective.

Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

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Performance

The bar chart and table below provide some indication of the risks of investing in the ILR Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.65% (Q1, 2019)
Lowest Quarterly Return: 0.00% (Q4, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	10-Years or Since Inception	Inception Date
Premier Class	0.04%	1.20%	0.69%	8/12/2004
Investment Class	0.00%	0.94%	0.48%	10/15/2007
Institutional Class	0.02%	-	1.13%	7/3/2018
Administration Class	-0.01%	1.00%	0.95%	8/29/2016
Investor Class	-0.01%	-	1.16%	7/13/2017

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Institutional Class
To establish an account	$25,000,000
To add to an existing account	No minimum
Administration Class
To establish an account	$1,000
To add to an existing account	No minimum
Investment Class
To establish an account	$250
To add to an existing account	No minimum
Investor Class
To establish an account	$10,000,000
To add to an existing account	No minimum
Premier Class
To establish an account	$250,000,000
To add to an existing account	No minimum
Opportunity Class
To establish an account	$25,000,000
To add to an existing account	No minimum

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You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Money Market Fund

Investment Objective

The investment objective of State Street Institutional Treasury Money Market Fund (the “Treasury Fund” or sometimes referred to in context as the “Fund”) is to seek a high level of current income consistent with preserving principal and liquidity and the maintenance of a stable $1.00 per share net asset value (“NAV”).

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Treasury Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. The expenses shown in the table and the Example reflect the expenses of the Fund and the Fund's proportionate share of the expenses of the State Street Treasury Money Market Portfolio (the “Treasury Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Management Fee	0.05%	0.05%	0.05%	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.05%	0.10%	0.00%	0.00%	0.00%
Other Expenses	0.10%	0.27%	0.32%	0.15%	0.07%	0.10%¹
Total Annual Fund Operating Expenses²	0.15%	0.37%	0.47%	0.20%	0.12%	0.15%

Other Expenses for the Opportunity Class shares are based on estimates for the current fiscal year.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), and its affiliates, may voluntarily reduce all or a portion of their fees and/or reimburse expenses of the Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”), or a yield below a specified level, which may vary from time to time in the Adviser's sole discretion. The Fund has agreed, subject to certain limitations, to reimburse the Adviser and its affiliates for the full dollar amount of any Voluntary Reduction incurred beginning on May 1, 2020. During the fiscal year ended December 31, 2021, the Adviser and its affiliates waived fees and/or reimbursed expenses under the Voluntary Reduction. Each of the Adviser and its affiliates may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund. Any future reimbursement by the Fund of the Voluntary Reduction would increase the Fund's expenses and may reduce the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield.

Example:

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	1 year	3 years	5 years	10 years
Institutional	$15	$48	$85	$192
Administration	$38	$119	$208	$468
Investment	$48	$151	$263	$591
Investor	$20	$64	$113	$255
Premier	$12	$39	$68	$154
Opportunity	$15	$48	$85	$192

Principal Investment Strategies

The Treasury Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government). The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term securities (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Treasury Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio, and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

Principal Risks

The Fund is subject to the following risks. You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

Money Market Risk: An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Although a money market fund generally seeks to preserve the value of its shares at $1.00 per share, there can be no assurance that it will do so, and it is possible to lose money by investing in a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause a money market fund's share price to fall below $1.00.

U.S. Treasury Obligations Risk: U.S. Treasury obligations may differ from other fixed income securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund's U.S. Treasury obligations to decline.

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Stable Share Price Risk: If the market value of one or more of the Fund's investments changes substantially, the Fund may not be able to maintain a stable share price of $1.00. This risk typically is higher during periods of rapidly changing interest rates or when issuer credit quality generally is falling, and is made worse when the Fund experiences significant redemption requests.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.57% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	10-Years or Since Inception	Inception Date
Premier Class	0.01%	1.00%	0.52%	10/25/2007
Institutional Class	0.01%	-	0.96%	7/30/2018
Administration Class	0.00%	-	0.84%	7/30/2018
Investment Class	0.01%	0.76%	0.38%	10/25/2007
Investor Class	0.01%	0.94%	0.94%	12/22/2016

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

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Purchase and Sale of Fund Shares

Purchase Minimums

Institutional Class
To establish an account	$25,000,000
To add to an existing account	No minimum
Administration Class
To establish an account	$1,000
To add to an existing account	No minimum
Investment Class
To establish an account	$250
To add to an existing account	No minimum
Investor Class
To establish an account	$10,000,000
To add to an existing account	No minimum
Premier Class
To establish an account	$250,000,000
To add to an existing account	No minimum
Opportunity Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

For U.S. federal income tax purposes, the Fund's distributions are expected to be taxed as ordinary income unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or individual retirement account. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

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Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

The investment objective of State Street Institutional Treasury Plus Money Market Fund (the “Treasury Plus Fund” or sometimes referred to in context as the “Fund”) is to seek a high level of current income consistent with preserving principal and liquidity and the maintenance of a stable $1.00 per share net asset value (“NAV”).

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Treasury Plus Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. The expenses shown in the table and the Example reflect the expenses of the Fund and the Fund's proportionate share of the expenses of the State Street Treasury Plus Money Market Portfolio (the “Treasury Plus Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Management Fee	0.05%	0.05%	0.05%	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.05%	0.10%	0.00%	0.00%	0.00%
Other Expenses	0.10%	0.27%	0.32%	0.15%	0.07%	0.10%¹
Total Annual Fund Operating Expenses²	0.15%	0.37%	0.47%	0.20%	0.12%	0.15%

Other Expenses for the Opportunity Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Institutional	$15	$48	$85	$192
Administration	$38	$119	$208	$468
Investment	$48	$151	$263	$591
Investor	$20	$64	$113	$255
Premier	$12	$39	$68	$154
Opportunity	$15	$48	$85	$192

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Treasury Plus Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio, and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	10-Years or Since Inception	Inception Date
Premier Class	0.02%	1.01%	0.52%	10/24/2007
Investment Class	0.01%	0.77%	0.39%	10/24/2007
Institutional Class	0.02%	-	0.97%	7/30/2018
Administration Class	0.00%	-	0.84%	7/30/2018
Investor Class	0.01%	0.95%	0.91%	10/14/2016

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Institutional Class
To establish an account	$25,000,000
To add to an existing account	No minimum
Administration Class
To establish an account	$1,000
To add to an existing account	No minimum
Investment Class
To establish an account	$250
To add to an existing account	No minimum
Investor Class
To establish an account	$10,000,000
To add to an existing account	No minimum
Premier Class
To establish an account	$250,000,000
To add to an existing account	No minimum
Opportunity Class
To establish an account	$25,000,000
To add to an existing account	No minimum

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You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

The investment objective of the State Street Institutional U.S. Government Money Market Fund (the “U.S. Government Fund” or sometimes referred to in context as the “Fund”) is to seek to maximize current income, to the extent consistent with the preservation of capital and liquidity and the maintenance of a stable $1.00 per share net asset value (“NAV”).

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the U.S. Government Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. The expenses shown in the table and the Example reflect the expenses of the Fund and the Fund's proportionate share of the expenses of the State Street U.S. Government Money Market Portfolio (the “U.S. Government Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Institutional	Administration	Investment	Investor	Premier	Opportunity
Management Fee	0.05%	0.05%	0.05%	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.05%	0.10%	0.00%	0.00%	0.00%
Other Expenses	0.10%	0.27%	0.32%	0.15%	0.07%	0.10%¹
Total Annual Fund Operating Expenses²	0.15%	0.37%	0.47%	0.20%	0.12%	0.15%

Other Expenses for the Opportunity Class shares are based on estimates for the current fiscal year.

Example:

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into account the effect of any current contractual fee waivers and/or reimbursements; and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 year	3 years	5 years	10 years
Institutional	$15	$48	$85	$192
Administration	$38	$119	$208	$468
Investment	$48	$151	$263	$591
Investor	$20	$64	$113	$255
Premier	$12	$39	$68	$154
Opportunity	$15	$48	$85	$192

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the U.S. Government Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio, and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

Principal Risks

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ment of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

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securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Significant Exposure to U.S. Government Agencies or Instrumentalities Risk: To the extent the Fund focuses its investments in securities issued or guaranteed by U.S. government agencies or instrumentalities, any market movements, regulatory changes or changes in political or economic conditions that affect the U.S. government agencies or instrumentalities in which the Fund invests may have a significant impact on the Fund's performance. Events that would adversely affect the market prices of securities issued or guaranteed by one government agency or instrumentality may adversely affect the market price of securities issued or guaranteed by other government agencies or instrumentalities.

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2013)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	10-Years or Since Inception	Inception Date
Premier Class	0.03%	1.02%	0.54%	10/25/2007
Investment Class	0.01%	0.78%	0.39%	10/17/2007
Administration Class	0.01%	0.84%	0.78%	8/23/2016
Institutional Class	0.03%	-	1.04%	1/18/2018
Investor Class	0.01%	0.95%	0.85%	3/21/2016

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

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Purchase and Sale of Fund Shares

Purchase Minimums

Institutional Class
To establish an account	$25,000,000
To add to an existing account	No minimum
Administration Class
To establish an account	$1,000
To add to an existing account	No minimum
Investment Class
To establish an account	$250
To add to an existing account	No minimum
Investor Class
To establish an account	$10,000,000
To add to an existing account	No minimum
Premier Class
To establish an account	$250,000,000
To add to an existing account	No minimum
Opportunity Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

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Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the ESG Liquid Reserves Fund, ILR Fund, U.S. Government Fund, the Treasury Fund and the Treasury Plus Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

ESG Liquid Reserves Fund

Principal Investment Strategies

The Adviser intends to consider ESG criteria at the time of purchase by using an ESG-related metric for each Fund investment. For most Fund investments, the Adviser uses a proprietary scoring system developed by SSGA that assigns an ESG rating, in the form of a “Responsibility” or “R-Factor^TM” score, to the issuer. The amount of the Fund's investments assigned an R-Factor^TM score will vary from time to time and can change significantly. The R-Factor^TM score measures the performance of a company's business operations and governance as related to financially material ESG challenges facing the issuer's industry. For example, for companies in the asset management industry, the R‑ FactorTM score currently uses metrics based on selling practices and product labeling, employee engagement / diversity and inclusion, product design and lifecycle management, business ethics, and systemic risk management. The R-Factor^TM score for each applicable issuer draws on a number of data sources, including third-party data providers, that provide metrics on a variety of ESG topics.

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Additional Information Regarding SASB. SASB is a non-profit organization that develops and maintains reporting standards intended to enable businesses around the world to identify, manage and communicate financially material sustainability information. SASB's framework consists of five broad sustainability dimensions or categories, including: environment, social capital, human capital, business model and innovation, and leadership and governance. The R-Factor^TM score

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only takes into account data relevant to each category when it is believed to be financially material to a company's industry. Each sustainability dimension or category consists of numerous sub-topics, including, but not limited to, air quality, energy management, human rights and community relations, customer welfare, labor practices, impact of climate change, and business ethics.

ILR Fund

Principal Investment Strategies

The ILR Fund follows a disciplined investment process in which SSGA FM bases its decisions on the relative attractiveness of different money market instruments. In the Adviser's opinion, the attractiveness of an instrument may vary depending on the general level of interest rates, as well as imbalances of supply and demand in the market. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

Treasury Fund

Principal Investment Strategies

The Treasury Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government). The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

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Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

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The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

Banking Companies Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). The performance of bank stocks may be affected by extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, and the interest rates and fees they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds, and can fluctuate significantly when interest rates change. Credit losses resulting from financial difficulties of borrowers can negatively impact the banking companies. Banks may also be subject to severe price competition. Competition among banking companies is high and failure to maintain or increase market share may result in lost market value.

Call/Prepayment Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by a Fund earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by a Fund are prepaid. In any such case, a Fund may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Fund's income.

Counterparty Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund, U.S. Government Fund and Treasury Plus Fund). A Fund will be subject to credit risk with respect to the counterparties with which a Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, a Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Credit Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund, U.S. Government Fund and Treasury Plus Fund). Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by a Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

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rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

Debt Securities Risk. The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of a Fund's fixed income securities to decrease, an adverse impact on the liquidity of a Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, a Fund's yield can be low, and a Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by a Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

ESG Investing Risk (principal risk for the ESG Liquid Reserves Fund). The Fund's incorporation of environmental, social and/or governance considerations in its investment process may cause it to make different investments than funds that have a similar investment universe and/or investment style but that do not incorporate such considerations in their investment strategy or processes. In applying ESG criteria to its investment decisions, the Fund may forgo higher yielding investments that it would invest in absent the application of its ESG investing criteria. The Fund's investment process may affect the Fund's exposure to certain investments, which may impact the Fund's relative investment performance depending on whether such investments are in or out of favor with the market. In addition, the Fund's investments in certain companies may be susceptible to various factors that may impact their businesses or operations, including costs associated with government budgetary constraints that impact publicly funded projects and clean energy initiatives, the effects of general economic conditions throughout the world, increased competition from other providers of services, unfavorable tax laws or accounting policies and high leverage. The Fund's portfolio managers rely on available information to assist in the ESG evaluation process, and the process employed for the Fund may differ from processes employed for other funds. The Fund will seek to identify companies that it believes meet its ESG criteria based on the data provided by third parties. The data provided by third parties may be incomplete, inaccurate or unavailable, which could cause the Adviser to incorrectly assess a company's ESG practices. The Fund may invest in companies that do not reflect the beliefs and values of any particular investor.

Due to constraints imposed by regulations applicable to money market funds or other considerations relating to credit quality, liquidity or yield, the Fund may be unable to successfully implement its ESG investment strategy. In addition, the Adviser generally will not sell a security as a result of a decline in an issuer's ESG rating, but will attempt to maintain a high R-Factor^TM score for the Fund's portfolio overall. As a result, if the R-Factor^TM score of a current Fund holding deteriorates, the Fund's new investment opportunities may be limited, since the Fund may be unable to invest in securities that are relatively lower-scoring.

Extension Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). During periods of rising interest rates, the average life of certain types of securities may be extended because of slower-than-expected principal payments. This may increase the period of time during which an investment earns a below-market interest rate, increase the security's duration and reduce the value of the security. Extension risk may be heightened during periods of adverse economic conditions generally, as payment rates decline due to higher unemployment levels and other factors.

Financial Institutions Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Some instruments are issued or guaranteed by financial institutions, such as banks and brokers, or are collateralized by securities issued or guaranteed by financial institutions. Changes in the creditworthiness of any of these institutions may adversely affect the values of instruments of issuers in financial industries. Financial institutions may be particularly sensitive to certain economic factors such as interest rate changes, adverse developments in the real estate market, fiscal and monetary policy and general economic cycles. Adverse developments in banking and other financial industries may cause a Fund to underperform relative to other funds that invest more broadly across different industries or have a smaller exposure to

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financial institutions. Changes in governmental regulation and oversight of financial institutions may have an adverse effect on the financial condition or the earnings or operations of a financial institution and on the types and amounts of businesses in which a financial institution may engage. An investor may be delayed or prevented from exercising certain remedies against a financial institution. The amount of a Fund's assets that may be invested in any financial institution, or financial institutions generally, may be limited by applicable law.

Income Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund and U.S. Government Fund). A Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by a Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Fund may limit the Fund's ability to achieve its objective.

Interest Rate Risk. Interest rate risk is the risk that the securities held by a Fund will decline in value because of increases in market interest rates. Duration is a measure used to determine the sensitivity of a security's price to changes in interest rates. Debt securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than debt securities with shorter durations. For example, the value of a security with a duration of five years would be expected to decrease by 5% for every 1% increase in interest rates. Falling interest rates also create the potential for a decline in a Fund's income and yield. Interest-only and principal-only securities are especially sensitive to interest rate changes, which can affect not only their prices but can also change the income flows and repayment assumptions about those investments. Variable and floating rate securities also generally increase or decrease in value in response to changes in interest rates, although generally to a lesser degree than fixed-rate securities. A substantial increase in interest rates may also have an adverse impact on the liquidity of a security, especially those with longer durations. Changes in governmental policy, including changes in central bank monetary policy, could cause interest rates to rise rapidly, or cause investors to expect a rapid rise in interest rates. This could lead to heightened levels of interest rate, volatility and liquidity risks for the fixed income markets generally and could have a substantial and immediate effect on the values of a Fund's investments.

Large Shareholder Risk. To the extent a large proportion of the interests of a Portfolio are highly concentrated or held by a small number of investors (or a single investor), including funds or accounts over which the Adviser has investment discretion, a Portfolio is subject to the risk that these investors will purchase or redeem Portfolio interests in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of a Portfolio to conduct its investment program. For example, they could require a Portfolio to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to investors, or a Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case a Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. A Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Liquidity Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Liquidity risk is the risk that a Fund may not be able to dispose of investments readily at a favorable time or prices (or at all) or at prices approximating those at which a Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity a Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

Low Short-Term Interest Rate Risk. During market conditions in which short-term interest rates are at low levels a Fund's yield can be very low. During these conditions, it is possible that a Fund will generate an insufficient amount of income to pay its expenses, and that it will not be able to pay a daily dividend and may have a negative yield (i.e., it may lose money on an operating basis). It is possible that a Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income.

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and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and a Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Money Market Fund Regulatory Risk. Money market funds and the securities they invest in are subject to comprehensive regulations. The enactment of new legislation or regulations, as well as changes in interpretation and enforcement of current laws, may affect the manner of operation, performance and/or yield of money market funds. The SEC has proposed amendments to money market fund regulation that if adopted as proposed would, among other things, increase the daily and weekly liquid asset requirements, remove liquidity fees and redemption gate provisions and require institutional prime money market funds to use swing pricing. Such amendments may, if adopted, limit the Fund's investment flexibility and reduce its ability to generate returns.

Money Market Risk-Floating NAV (principal risk for the ESG Liquid Reserves Fund and ILR Fund). The Fund does not maintain a constant net asset value per share. The value of the Fund's Shares is calculated to four decimal places and will vary reflecting the value of the portfolio of investments held by the Fund. It is possible to lose money by investing in the Fund.

Money Market Risk (principal risk for the U.S. Government Fund, Treasury Fund and Treasury Plus Fund). An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Although a money market fund generally seeks to preserve the value of its shares at $1.00 per share, there can be no assurance that it will do so, and it is possible to lose money by investing in a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause a money market fund's share price to fall below $1.00. It is possible that a money market fund will issue and redeem shares at $1.00 per share at times when the fair value of the money market fund's portfolio per share is more or less than $1.00. A money market fund may be permitted or required to impose redemption fees or to impose limitations on redemptions during periods of high illiquidity in the markets for the investments held by it. None of State Street Corporation, State Street, State Street Global Advisors, SSGA FM or their affiliates (collectively, the “State Street Entities”) guarantee the value of an investment in a money market fund at $1.00 per share. Investors should have no expectation of capital support to a money market fund from the State Street Entities.

Mortgage-Related and Other Asset-Backed Securities Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund and U.S. Government Fund). Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically struc-

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tured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Non-U.S. Securities Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Fund invests could cause the Fund's investments in that country to experience gains or losses.

Rapid Changes in Interest Rates. The values of instruments held by a Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause a Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses would negatively affect the NAV per share of the ILR Fund and the ESG Liquid Reserves Fund and, in the case of the U.S. Government Fund, Treasury Fund and Treasury Plus Fund, could impair the Fund's ability to maintain a stable share price of $1.00.

Reinvestment Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund and U.S. Government Fund). Income from a Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by a Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

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Repurchase Agreement Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund, U.S. Government Fund and Treasury Plus Fund). A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

Restricted Securities Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). A Fund may hold securities that have not been registered for sale to the public under the U.S. federal securities laws pursuant to an exemption from registration. These securities may be less liquid than securities registered for sale to the general public. The liquidity of a restricted security may be affected by a number of factors, including, among others: (i) the creditworthiness of the issuer; (ii) the frequency of trades and quotes for the security; (iii) the number of dealers willing to purchase or sell the security and the number of other potential purchasers; (iv) dealer undertakings to make a market in the security; (v) the nature of any legal restrictions governing trading in the security; and (vi) the nature of the security and the nature of marketplace trades. There can be no assurance that a liquid trading market will exist at any time for any particular restricted security. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

Risk of Investment in Other Pools (principal risk for the ESG Liquid Reserves Fund and ILR Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Risks Related to ECDs, ETDs and YCDs (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Banks issuing ECDs, ETDs and YCDs are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of foreign issuers also involve risks such as future unfavorable political and economic developments, withholding or other tax, seizures of foreign deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

Section 4(a)(2) Commercial Paper and Rule 144A Securities Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). A Fund may invest in commercial paper issued in reliance on the private placement exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the “1933 Act”). This commercial paper is commonly called “Section 4(a)(2) paper.” A Fund may also invest in securities that may be offered and sold only to “qualified institutional buyers” under Rule 144A of the 1933 Act (“Rule 144A securities”).

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Section 4(a)(2) paper is sold to institutional investors who must agree to purchase the paper for investment and not with a view to public distribution. Any resale by the purchaser must be in a transaction exempt from the registration requirements of the 1933 Act. Section 4(a)(2) paper normally is resold to other institutional investors like a Fund through or with the assistance of the issuer or investment dealers that make a market in Section 4(a)(2) paper. As a result, it suffers from liquidity risk, the risk that the securities may be difficult to value because of the absence of an active market and the risk that it may be sold only after considerable expense and delay, if at all. Rule 144A securities generally must be sold only to other qualified institutional buyers.

Section 4(a)(2) paper and Rule 144A securities will not be considered illiquid for purposes of a Fund's limitation on illiquid securities if the Adviser (pursuant to guidelines adopted by the Board) determines that a liquid trading market exists for the securities in question. There can be no assurance that a liquid trading market will exist at any time for any particular Section 4(a)(2) paper or Rule 144A securities.

Significant Exposure to U.S. Government Agencies or Instrumentalities Risk (principal risk for the U.S. Government Fund). To the extent a Fund focuses its investments in securities issued or guaranteed by U.S. government agencies or instrumentalities, any market movements, regulatory changes or changes in political or economic conditions that affect the U.S. government agencies or instrumentalities in which the Fund invests may have a significant impact on a Fund's performance. Events that would adversely affect the market prices of securities issued or guaranteed by one government agency or instrumentality may adversely affect the market price of securities issued or guaranteed by other government agencies or instrumentalities.

Stable Share Price Risk (principal risk for the U.S. Government Fund, Treasury Fund and Treasury Plus Fund). If the market value of one or more of the Fund's investments changes substantially, the Fund may not be able to maintain a stable share price of $1.00. This risk typically is higher during periods of rapidly changing interest rates or when issuer credit quality generally is falling, and is made worse when the Fund experiences significant redemption requests.

U.S. Government Securities Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund and U.S. Government Fund). U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor supported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of a Fund's investments.

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sury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

Variable and Floating Rate Securities Risk. Variable or floating rate securities are debt securities with variable or floating interest rates payments. Variable or floating rate securities bear rates of interest that are adjusted periodically according to formulae intended generally to reflect market rates of interest and allow a Fund to participate (determined in accordance with the terms of the securities) in increases in interest rates through upward adjustments of the coupon rates on the securities. However, during periods of increasing interest rates, changes in the coupon rates may lag behind the changes in market rates or may have limits on the maximum increases in coupon rates. Alternatively, during periods of declining interest rates, the coupon rates on such securities will typically readjust downward resulting in a lower yield. A Fund may also invest in variable or floating rate equity securities, whose dividend payments vary based on changes in market rates of interest or other factors.

Zero-Coupon Bond Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Zero-coupon bonds are debt obligations that are generally issued at a discount and payable in full at maturity, and that do not provide for current payments of interest prior to maturity. Zero-coupon bonds usually trade at a deep discount from their face or par values and are subject to greater market value fluctuations from changing interest rates than debt obligations of comparable maturities that make current distributions of interest. When interest rates rise, the values of zero-coupon bonds fall more rapidly than securities paying interest on a current basis, because a Fund is unable to reinvest interest payments at the higher rates.

Additional Information About Non-Principal Investment Strategies and Risks

The investments described below reflect the Funds' and the Portfolios' current practices. In addition to the principal risks described above, other risks are described in some of the descriptions of the investments below:

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ates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Funds) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Funds, the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

LIBOR Risk. A Fund's payment obligations, financing terms and investments in certain instruments (including debt securities and derivatives) may rely in some fashion upon the London-Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration (the administrator of LIBOR), that banks offer to charge one another for the use of short-term money. In 2017, the U.K. Financial Conduct Authority announced its intention to cease compelling banks to provide the quotations needed to sustain LIBOR after 2021. IBA ceased publication of most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of a majority of U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. Actions by regulators have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Various financial industry groups have been planning for the transition away from LIBOR and markets are developing in response to these new rates, but questions around the liquidity of the new rates and how to appropriately adjust these rates to eliminate any economic value transfer at the time of transition remain a significant concern. The transition away from and eventual elimination of LIBOR may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include “fall back” provisions addressing the transition from LIBOR. Uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by a Fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to a Fund.

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Risk of Investment in Other Pools (risk for the U.S. Government Fund, Treasury Fund and Treasury Plus Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Temporary Defensive Positions. In response to actual or perceived adverse market, economic, political, or other conditions, a Fund may (but will not necessarily), without notice, depart from its principal investment strategies by temporarily investing for defensive purposes. While investing defensively, the Fund may maintain a substantial portion of its assets in cash, on which the Fund may earn little if any income. If a Fund invests for defensive purposes, it may not achieve its investment objective. In addition, the defensive strategy may not work as intended.

Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

SSGA FM intends to support inclusion and diversity initiatives by making an annual donation out of its own assets in an amount equal to or more than 20% of the annual management fees received with respect to the assets invested in the Opportunity Class shares of each Fund. Donations will be made to charitable organizations working in congruence with State Street Corporation's 10 Actions to Address Racism and Inequality. Management fees are determined net of fee waivers, expense reimbursements, net asset value support payments and similar amounts. The donation program will continue throughout the life of the Opportunity Class shares. The charitable organizations will not participate in, or have any influence on the day‑to‑day operations of, the Funds or the Adviser's management of the Funds.

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.00% for ESG Liquid Reserves Portfolio, 0.05% for Money Market Portfolio, 0.05% for Treasury Portfolio 0.05% for Treasury Plus Portfolio and 0.05% for U.S. Government Portfolio.

Total Annual Fund Operating Expense Waivers. SSGA FM, as the investment adviser to each Fund is contractually obligated, through April 30, 2023 (i) to waive up to the full amount of the advisory fee payable by each Fund, and/or (ii) to reimburse a Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.07% of average daily net assets on an annual basis (the “Total Annual Fund Operating Expense Waiver”). The Total Annual Fund Operating Expense Waiver may not be terminated prior to April 30, 2023 with respect to any Fund except with approval of the Fund's Board of Trustees.

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In addition to any contractual expense limitation for a Fund which is described in the Fund Summaries, each of the Adviser and State Street Global Advisors Funds Distributors, LLC (each a “Service Provider”) also may voluntarily reduce all or a portion of its fees and/or reimburse expenses for a Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”). The Adviser may, in its sole discretion, implement the Voluntary Reduction for some Funds, or some share classes of a Fund, and not others. The amount of any Voluntary Reduction may differ between Funds and share classes in the Adviser's sole discretion. The business objectives of the Adviser and its affiliates and their broader relationships with certain Fund shareholders, Financial Intermediaries or distribution channels could give the Adviser an incentive to implement the Voluntary Reduction for some Funds or share classes and not others, or to implement it to a greater degree for some Funds or share classes than others. Under an agreement with the Service Providers relating to the Voluntary Reduction, the Funds and the Portfolios have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from a Fund.

A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one‑day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

SSGA FD serves as the Funds' shareholder servicing agent pursuant to the Shareholder Servicing Agreement between SSGA FD and the Trust and receives fees from the Funds for the provision and procurement of applicable services. Please see the SAI for more information on SSGA FD's role as the Funds' shareholder servicing agent.

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Additional Information

Shareholder Information

Determination of Net Asset Value

For the ESG Liquid Reserves Fund and ILR Fund

The ESG Liquid Reserves Fund and ILR Fund each determines its NAV per share three times each day on which the New York Stock Exchange (the “NYSE”), the Federal Reserve banks and State Street are open for business (a “Business Day”) at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The price for Fund shares is the NAV next calculated after the purchase order is accepted by a Fund. Orders accepted before 12:00 p.m. will receive the 12:00 p.m. NAV, orders accepted before 3:00 p.m. will receive the 3:00 p.m. NAV, and orders accepted after 3:00 p.m. will receive 8:00 a.m. NAV calculated on the following Business Day. The Fund calculates its NAV to four decimal places.

The NAV of each class of a Fund's shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding. Each Fund values each security or other investment pursuant to guidelines adopted by the Board of Trustees. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent that a Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

For the U.S. Government Fund, Treasury Plus Fund and Treasury Fund

The Treasury Plus Fund and the U.S. Government Fund each determines its NAV per share once each Business Day at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event those Funds will determines their NAVs at the earlier closing time. The Treasury Fund determines its NAV per share once each Business Day at 2:30 p.m. ET, or the close of the NYSE, whichever is earlier (the time when a Fund determines its NAV per share is referred to herein as the “Valuation Time”). Each Fund seeks to maintain a $1.00 per share NAV and, accordingly, uses the amortized cost valuation method, in compliance with the risk limiting conditions of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”), to value its portfolio instruments. The amortized cost valuation method initially prices an instrument at its cost and thereafter assumes a constant amortization to maturity of any discount or premium, regardless of the impact of fluctuating interest rates on the market value of the instrument.

For all Funds

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Pricing does not occur on NYSE holidays. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. The Funds reserve the right to accept orders to purchase or redeem shares, or to continue to accept such orders following the close of the NYSE, on any day that is not a Business Day or any day on which the NYSE closes early, provided the Federal Reserve remains open. As noted in this Prospectus, certain Funds may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when a Fund does not price its shares. Consequently, the NAV of a Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's shares. The Funds also may establish special hours on those days to determine each Fund's NAV. In the event that the Funds invoke the right to accept orders to purchase or redeem shares on any day that is not a Business Day or adopt special hours of operation, the Fund will post advance notice of these events at:www.ssga.com.

If you hold shares of a Fund through a broker-dealer or other financial intermediary, your intermediary may offer additional services and account features that are not described in this Prospectus. Please contact your intermediary directly for an explanation of these services.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

The Funds offer six classes of shares through this Prospectus: Institutional Class, Administration Class, Investment Class, Investor Class, Premier Class and Opportunity Class is available to you subject to the eligibility requirements set forth below. All classes of a Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. You should choose the class with the expense structure that best meets your needs for which you are eligible. In choosing a share class, you should consider the amount you plan to invest. Your investment professional can help you choose the share class that best suits your investment needs.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their family. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

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	Institutional Class	Administration Class	Investment Class	Investor Class	Premier Class	Opportunity Class
Minimum Initial Investment	$25,000,000	$1,000	$250	$10,000,000	$250,000,000	$25,000,000
Maximum Investment	None.	None.	None.	None.	None.	None.
Initial Sales Charge	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No.	No.	No.	No.	No.	No.
Distribution and/or Service (12b-1) Fees	No.	0.05% annual fee.	0.10% annual fee.	No.	No.	No.
Redemption Fees	No.	No.	No.	No.	No.	No.

Investors pay no sales load to invest in the shares of the Funds. The price for Fund Shares is the NAV per share.

Purchase requests received by a Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Times (for the ILR Fund generally, 3:00 p.m. ET, unless the Fund closes earlier) will earn dividend accrual for that purchase.

All purchases that are made by check will be priced with the last valuation price and begin earning dividends the following Business Day after the day the order is accepted. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) All purchase orders are subject to acceptance by the Funds. The Funds intend to be as fully invested as is practicable; therefore, investments must be made in Federal Funds (i.e., monies credited to the account of the Funds' custodian bank by a Federal Reserve Bank).

The minimum initial investment in Institutional Class, Administration, Investment, Investor, Premier and Opportunity shares of the Funds is $25 million, $1 thousand, $250, $10 million, $250 million and $25 million, respectively, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include but are not limited to accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Funds and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below). The Funds require prior notification of subsequent investments in excess of $10 million for the Treasury Fund and $50 million for the U.S. Government Fund and Treasury Plus Fund.

The Funds reserve the right to cease accepting investments at any time or to reject any investment order. In addition, the U.S. Government Fund and the Treasury Plus Fund may limit the amount of a purchase order received after 3:00 p.m. ET. The Treasury Fund may limit the amount of a purchase order received after 12:00 p.m. (noon) ET. The ESG Liquid Reserves Fund and ILR Fund each determine its NAV at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The 8:00 a.m., 12:00 p.m. and 3:00 p.m. NAV calculation times are intended to facilitate same day settlement.

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How to Purchase Shares

By Mail:

An initial investment in the Funds must be preceded or accompanied by a completed, signed Institutional Account Application Form, sent to:
State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

An initial investment in the Funds must be preceded or accompanied by a completed, signed Institutional Account Application Form, faxed to (816) 218-0400. Call the Fund at (866) 392-0869 between the hours of 7:00 a.m. ET and 5:00 p.m. ET to:

➣ confirm receipt of the faxed Institutional Account Application Form (initial purchases only),
➣ request your new account number (initial purchases only),
➣ confirm the amount being wired and wiring bank, and
➣ receive a confirmation number for your purchase order (your trade is not effective until you have received a confirmation number from the Fund).

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

On Columbus Day and Veterans Day, you will not be able to purchase shares by wiring Federal Funds because the Federal Funds wiring does not occur on those days. Payment for Fund Shares must be in Federal Funds (or converted to Federal Funds by the Transfer Agent) by the close of the Federal Reserve.

The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Automatic Investment Plan. An Automatic Investment Plan is available for all operational State Street Funds that offer the Administration Class shares. Once an initial investment has been accepted, you may elect to make automatic subsequent investments of $100 or more on a periodic basis (i.e., monthly, quarterly, semi-annually, or annually) by authorizing the Fund to debit your bank checking or savings account through Automated Clearing House (ACH). For the ESG Liquid Reserves Fund and ILR Fund Administration Class shares, purchases made through the Automated Investment Plan will be priced at the last valuation price on the day of the transaction.Once this option has been established, you may call the State Street Funds to make additional automatic purchases, to change the amount of the existing automatic purchase, or to discontinue the service. The Fund reserves the right to cancel your Automatic Investment Plan if any correspondence sent by the Fund to your address of record is returned by the postal service or other delivery service as “undeliverable.” Ask your financial adviser or financial intermediary for details.

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Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form.

For the ESG Liquid Reserves Fund and ILR Fund

If the ESG Liquid Reserves Fund or the ILR Fund receives a redemption order in good form prior to its last valuation time (generally, 3:00 p.m. ET, unless the Fund closes earlier) on a Business Day, the Fund typically sends payment for redeemed shares on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after the last valuation time (generally, 3:00 p.m. ET, unless the Fund closes earlier) a Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). Each Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

Certain special limitations affecting redemptions. The SEC has implemented a number of requirements, including liquidity fees and redemption gates, for money market funds based on the amount of fund assets in “weekly liquid assets,” which generally includes cash, direct obligations of the U.S. government, certain other U.S. government or agency securities, and securities that will mature or are subject to a demand feature that is exercisable and payable within five Business Days. Each Fund will pass through to its investors any liquidity fee or suspension of redemptions imposed by the corresponding Portfolio on the same terms and conditions as imposed by the Portfolio on the Fund.

If a Portfolio's weekly liquid assets fall below 30% of its total assets and the Portfolio's Board of Trustees determines it is in the best interests of the Portfolio, the Portfolio may immediately impose a liquidity fee of no more than 2% and/or temporarily suspend redemptions for up to 10 Business Days in any 90 day period. If a Portfolio's weekly liquid assets fall below 10% of its total assets at the end of any Business Day, the Portfolio will impose a liquidity fee of 1% on all redemptions beginning on the next Business Day, unless the Portfolio's Board determines that imposing such a fee would not be in the best interests of the Portfolio or determines that a lower or higher fee (not to exceed 2%) would be in the best interests of the Portfolio, which would remain in effect until weekly liquid assets return to 30% or the Portfolio's Board determines that the fee is no longer in the best interests of the Portfolio. All liquidity fees payable by a Fund would be passed through to its shareholders, would be payable to the Portfolio and could offset any losses realized by the Portfolio when seeking to honor redemption requests. If liquidity fees are imposed or redemptions are suspended by a Portfolio, the corresponding Fund will notify shareholders on the Fund's website. Each Fund expects to treat such liquidity fees paid to its corresponding Portfolio as reducing proceeds paid to shareholders in redemption of Fund shares, and not constituting income to the Portfolio or the Fund. There may be circumstances under which a Fund may impose its own liquidity fees and/or suspend redemptions based on the level of the Fund's own weekly liquid assets, in which case the Fund will also provide notice to shareholders.

If a Portfolio's weekly liquid assets fall below 10% of its assets on a Business Day, the Portfolio may cease honoring redemptions and liquidate in the discretion of the Portfolio's Board. If a Fund is notified that its Portfolio's weekly liquid assets fall below 10% of the Portfolio's assets and the Portfolio has suspended redemptions and intends to liquidate, the Fund may also do so in the discretion of the Fund's Board. There may be circumstances under which a Fund may cease honoring redemptions and liquidate in the discretion of its Board based on the level of the Fund's own weekly liquid assets. If a Fund ceases honoring redemptions and determines to liquidate, the ILR Fund expects that it would notify shareholders on the Fund's website. Distributions to shareholders of liquidation proceeds may occur in one or more disbursements.

For the U.S. Government Fund, Treasury Fund and the Treasury Plus Fund

If the Treasury Fund, the Treasury Plus Fund or the U.S. Government Fund receives a redemption order in good form prior to 2:30 p.m. ET for the Treasury Fund and 5:00 p.m. ET for the Treasury Plus Fund and U.S. Government Fund on a Business Day, the Fund typically expects to pay out redemption proceeds on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. No dividends will be paid on shares that are redeemed and wired the same day.

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If redemption proceeds are sent by check, the Fund pays out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after 2:30 p.m. ET for the Treasury Fund and 5:00 p.m. ET for the U.S. Government Fund and the Treasury Plus Fund, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent), but no later than the following Business Day. The Fund may postpone and/or suspend redemption and payment beyond the foregoing time periods only as follows:

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;
c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

The Treasury Fund, Treasury Plus Fund and U.S. Government Fund are government money market funds that have not elected to be subject to the fees and gates provisions of Rule 2a-7. Although each Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

For the ESG Liquid Reserves Fund, ILR Fund, Treasury Fund and Treasury Plus Fund

Each of the Treasury Fund and Treasury Plus Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. With respect to the ESG Liquid Reserves Fund, ILR Fund, the Treasury Fund and the Treasury Plus Fund, the right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed beyond 7 days in accordance with Section 22(e) of the 1940 Act and the rules thereunder, including during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or if an emergency exists as a result of which disposal by the Fund of securities owned by it is not reasonably practicable or it is not reasonably practicable for the Fund fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of shareholders of the Funds. Although each of the Treasury Fund and the Treasury Plus Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption. The ESG Liquid Reserves Fund and the ILR Fund also may permanently suspend redemptions and liquidate if, among other reasons, (i) a Fund, at the end of a business day, has invested less than 10% of its total assets in weekly liquid assets and (ii) the Board, including the Independent Trustees, irrevocably has approved the liquidation of a Fund.

For All Funds

Under normal circumstances, the Funds expect to meet redemption requests by using cash or cash equivalents in its portfolio and/or selling portfolio assets to generate cash. The Funds also may pay redemption proceeds using cash obtained through borrowing arrangements that may be available from time to time.

A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

During periods of deteriorating or stressed market conditions or during extraordinary or emergency circumstances, a Fund may be more likely to pay redemption proceeds with cash obtained through short-term borrowing arrangements (if available) or by giving you securities.

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A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as deter- mined by their policies and may be waived in the Adviser's discretion. The Funds reserve the right to modify minimum account requirements at any time with or without prior notice. The Funds also reserve the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Funds will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Funds calculate their NAVs earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Funds reserve the right to waive medallion guarantee requirements, require a medallion guarantee under other circumstances or reject or delay redemption if the medallion guarantee is not in good form. Medallion guarantees may be provided by an eligible financial institution such as a commercial bank, a Financial Industry Regulatory Authority, Inc. (“FINRA”) member firm such as a stock broker, a savings association or a national securities exchange. A notary public cannot provide a medallion guarantee. The Funds reserve the right to reject a medallion guarantee if it is not provided by a STAMP Medallion guarantor.

About Telephone Transactions. Telephone transactions are convenient but are not free from risk. Neither the Funds nor the Funds' agents will be responsible for any losses resulting from unauthorized telephone transactions if reasonable security procedures are followed. In addition, you are responsible for: (i) verifying the accuracy of all data and information transmitted by telephone, (ii) verifying the accuracy of your account statements immediately upon receipt, and (iii) promptly notifying the Funds of any errors or inaccuracies, including, without limitation, any errors or inaccuracies relating to shareholder data or information transmitted by telephone. During periods of heavy market activity or other times, it may be difficult to reach the Funds by telephone. If you are unable to reach us by telephone, consider sending written instructions.

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The Funds may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Automatic Withdrawal Plan. An Automatic Withdrawal Plan is available for all operational State Street Funds that offer the Administration Class shares, except for the State Street Institutional Liquid Reserves Fund. If your account balance is over $10,000, you may request periodic (i.e., monthly, quarterly, semi-annually, or annually) automatic cash withdrawals on any Business Day of $100 or more, which can be mailed to you, or any person or entity, you designate or sent through Automated Clearing House (ACH) to your designated bank account. Proceeds from such withdrawals will be transmitted to your designated bank account two Business Days after the redemption of shares occurs. No interest will accrue on the amounts represented by the uncashed redemption check(s). Ask your financial adviser or financial intermediary for details.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of a Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Currently, exchanging shares is allowed from/to the Treasury Plus Fund, U.S. Government Fund, and Treasury Fund. Exchanges may be made between different Funds within the same class (i.e. Institutional Class shares for Institutional Class shares; Investor Class shares for Investor Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected.

Excessive Trading

Because the Funds are money market funds, the Funds' Board has not adopted policies and procedures with respect to frequent purchases and redemptions of Fund shares by Fund shareholders. Nonetheless, the Funds may take any reasonable action that they deem necessary or appropriate to prevent excessive trading in Fund shares without providing prior notification to the account holder. Such action may include rejecting any purchase, in whole or part, including, without limitation, by a person whose trading activity in Fund shares may be deemed harmful to the Fund. While the Funds attempt to discourage such excessive trading, there can be no guarantee that they will be able to identify investors who are engaging in excessive trading or limit their trading practices. Additionally, frequent trades of small amounts may not be detected. The Funds recognize that they may not always be able to detect or prevent excessive trading or other activity that may disadvantage the Funds or their shareholders.

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

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If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund).

Dividends, Distributions and Tax Considerations

The Funds intend to declare dividends on shares from net investment income daily and pay them as of the last Business Day of each month. Distributions from capital gains, if any, will be made annually in December. Dividends of investment income and capital gain distributions will be paid in additional shares on the reinvestment date unless you have elected to receive them in cash. No interest will accrue on the amounts represented by uncashed distribution checks. If you have elected to receive distributions by check, and the postal or other delivery service is unable to deliver the checks because of an incorrect mailing address, or if a distribution check remains uncashed for six months, the uncashed distribution and all future distributions will be reinvested at the then-current NAV of the Fund.

Each Fund has elected to be treated as a regulated investment company and intends each year to qualify and to be eligible to be treated as such. A regulated investment company generally is not subject to tax at the corporate level on income and gains that are timely distributed to shareholders. In order to qualify and be eligible for treatment as a regulated investment company, a Fund must, among other things, satisfy diversification, 90% gross income and distribution requirements. A Fund's failure to qualify as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders.

Each Fund invests substantially all of its investable assets in a corresponding Portfolio that is treated as a partnership for U.S. federal income tax purposes. Therefore, the nature and character of each Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and each Fund will be allocated its share of the corresponding Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of a Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of a Fund will be to the Fund's allocable share of the assets of the corresponding Portfolio.

Distributions are taxable to you even if they are paid from income or gains earned by a Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of a Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Fund's shares, and, in general, as capital gain thereafter.

When the NAV of Fund Shares varies from a shareholder's tax basis in such shares, including when the NAV of such Fund Shares varies from $1.0000 per share, the shareholder generally will realize a gain or loss upon the redemption or other taxable disposition of such Fund Shares. Any such gain generally would be taxable to you as either short-term or long-term capital gain, depending upon how long you held the Fund Shares. The Internal Revenue Service (the “IRS”) has issued final regulations and published guidance that permit a simplified method of accounting for gains and losses realized upon the disposition of money market fund shares. Shareholders should see the SAI for further information.

A Fund's and a Portfolio's income from or proceeds of investments in non-U.S. assets may be subject to non-U.S. with-

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holding and other taxes. This will decrease the Fund's return on securities subject to such taxes. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes. Although such taxes will reduce a Fund's taxable income, shareholders generally will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Portfolio or Fund.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

The U.S. Treasury and IRS generally require a Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Internal Revenue Code of 1986, as amended, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Funds have adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which a Fund may compensate SSGA FD (or others) for services in connection with the distribution of a Fund's shares and for services provided to Fund shareholders (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.05% and 0.10% of each Fund's net assets attributable to its Administration Class shares and Investment Class shares, respectively. Because these fees are paid out of the assets of a Fund attributable to its shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges. Long-term shareholders of the Fund may pay more in Rule 12b-1 fees than the economic equivalent of the maximum front-end sales charge permitted by the FINRA.

A Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of that Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

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Third-Party Transactions. The State Street Funds have authorized certain Financial Intermediaries to accept purchase, redemption and exchange orders on the State Street Funds' behalf. Orders received for a State Street Fund by a Financial Intermediary that has been authorized to accept orders on the Fund's behalf (or other Financial Intermediaries designated by the Financial Intermediary) will be deemed accepted by the Fund at the time they are received by the Financial Intermediary and will be priced based on the Fund's next NAV determination as long as the Financial Intermediary transmits the order in good form and in a timely manner to the applicable State Street Fund(s). For the ELR Fund and ILR Fund, the State Street Funds will be the sole party to determine if a trade is received in good order. The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to a Fund.

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Financial Highlights

The financial highlight tables are intended to help you understand each Fund's financial performance for the past five fiscal years or, if shorter, the period since each class' inception. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in each Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with each Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of each Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET ESG LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	For the Period 12/20/19*- 12/31/19
Net asset value, beginning of period	$1.0002	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)	0.0054	0.0006
Net realized and unrealized gain (loss)	—	0.0002	0.0000(b)
Total from investment operations	0.0000(b)	0.0056	0.0006
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0054)	(0.0006)
Net asset value, end of period	$1.0001	$1.0002	$1.0000
Total return (c)	0.04%	0.56%	0.06%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$5,519	$23,023	$50
Ratios to Average Net Assets:
Total expenses	0.19%	0.22%	0.31%(d)
Net expenses	0.11%	0.11%	0.11%(d)
Net investment income (loss)	0.06%	0.12%	1.85%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET ESG LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investor Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	For the Period 12/20/19*- 12/31/19
Net asset value, beginning of period	$1.0002	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0049	0.0006
Net realized and unrealized gain (loss)	—	0.0002	0.0000(b)
Total from investment operations	0.0001	0.0051	0.0006
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0049)	(0.0006)
Total distributions	(0.0001)	(0.0049)	(0.0006)
Net asset value, end of period	$1.0002	$1.0002	$1.0000
Total return (c)	0.01%	0.51%	0.06%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50	$50	$50
Ratios to Average Net Assets:
Total expenses	0.23%	0.29%	0.36%(d)
Net expenses	0.16%	0.16%	0.16%(d)
Net investment income (loss)	0.00%(e)	0.49%	1.80%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.
(e)	Amount is less than 0.005%.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET ESG LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Premier Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	For the Period 12/04/2019 *- 12/31/19
Net asset value, beginning of period	$1.0002	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)	0.0058	0.0013
Net realized and unrealized gain (loss)	—	0.0002	0.0000(b)
Total from investment operations	0.0000(b)	0.0060	0.0013
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0058)	(0.0013)
Total distributions	(0.0001)	(0.0058)	(0.0013)
Net asset value, end of period	$1.0001	$1.0002	$1.0000
Total return (c)	0.07%	0.60%	0.13%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,297,099	$903,258	$881,217
Ratios to Average Net Assets:
Total expenses	0.15%	0.21%	0.23%(d)
Net expenses	0.08%	0.08%	0.08%(d)
Net investment income (loss)	0.08%	0.61%	1.75%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET ESG LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Opportunity Class (a)
	For the Period 10/28/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)
Net realized and unrealized gain (loss)	—
Total from investment operations	0.0000(b)
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$0.9999
Total return (c)	(0.00)%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.18%(e)
Net expenses	0.12%(e)
Net investment income (loss)	0.02%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 7/6/18*- 12/31/18
Net asset value, beginning of period	$1.0003	$1.0002	$1.0001	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0054	0.0217	0.0108
Net realized and unrealized gain (loss)	0.0001	0.0002	0.0009	0.0001
Total from investment operations	0.0002	0.0056	0.0226	0.0109
Distributions to shareholders from:
Net investment income	(0.0002)	(0.0055)	(0.0225)	(0.0108)
Net asset value, end of period	$1.0003	$1.0003	$1.0002	$1.0001
Total return (b)	0.02%	0.56%	2.28%	1.08%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$80,594	$153,757	$183,304	$55
Ratios to Average Net Assets:
Total expenses	0.15%	0.15%	0.16%	0.15%(c)
Net expenses	0.15%	0.15%	0.15%	0.15%(c)
Net investment income (loss)	0.03%	0.57%	2.17%	2.21%(c)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Administration Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0001	$1.0001	$0.9999	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)	0.0039	0.0206	0.0174	0.0080
Net realized and unrealized gain (loss)	(0.0001)	—	(0.0001)	(0.0001)	0.0000(b)
Total from investment operations	(0.0001)	0.0039	0.0205	0.0173	0.0080
Distributions to shareholders from:
Net investment income	—	(0.0039)	(0.0203)	(0.0174)	(0.0080)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	—	(0.0039)	(0.0203)	(0.0174)	(0.0080)
Net asset value, end of period	$1.0000	$1.0001	$1.0001	$0.9999	$1.0000
Total return (c)	(0.01)%	0.39%	2.07%	1.75%	0.80%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$663,480	$567,550	$613,074	$956,750	$831,606
Ratios to Average Net Assets:
Total expenses	0.37%	0.37%	0.38%	0.37%	0.37%
Net expenses	0.17%	0.32%	0.37%	0.37%	0.37%
Net investment income (loss)	0.00%(d)	0.43%	2.06%	1.74%	0.80%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investment Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0002	$1.0002	$1.0000	$0.9999	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000	0.0036	0.0201	0.0164	0.0070
Net realized and unrealized gain (loss)	—	—	(0.0003)	0.0001	(0.0001)
Total from investment operations	0.0000(b)	0.0036	0.0198	0.0165	0.0069
Distributions to shareholders from:
Net investment income	—	(0.0036)	(0.0196)	(0.0164)	(0.0070)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	—	(0.0036)	(0.0196)	(0.0164)	(0.0070)
Net asset value, end of period	$1.0002	$1.0002	$1.0002	$1.0000	$0.9999
Total return (c)	0.00%(d)	0.37%	1.99%	1.67%	0.69%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$6	$6	$12	$23	$5,547
Ratios to Average Net Assets:
Total expenses	0.48%	0.45%	0.47%	0.47%	0.47%
Net expenses	0.17%	0.35%	0.45%	0.47%	0.47%
Net investment income (loss)	(0.03)%	0.38%	2.01%	1.18%	0.70%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investor Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	For the Period 7/13/17* - 12/31/17
Net asset value, beginning of period	$1.0002	$1.0001	$0.9999	$0.9999	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)	0.0049	0.0219	0.0191	0.0055
Net realized and unrealized gain (loss)	(0.0001)	0.0002	0.0003	—	(0.0001)
Total from investment operations	(0.0001)	0.0051	0.0222	0.0191	0.0054
Voluntary expense reimbursement from Affiliate	—	—	—	—	0.0000(b)
Distributions to shareholders from:
Net investment income	(0.0000)(b)	(0.0050)	(0.0220)	(0.0191)	(0.0055)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0000)(b)	(0.0050)	(0.0220)	(0.0191)	(0.0055)
Net asset value, end of period	$1.0001	$1.0002	$1.0001	$0.9999	$0.9999
Total return (c)	(0.01)%	0.51%	2.24%	1.92%	0.54%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$131,790	$97,898	$36,424	$40,881	$34,361
Ratios to Average Net Assets:
Total expenses	0.20%	0.20%	0.21%	0.20%	0.20%(d)
Net expenses	0.17%	0.20%	0.20%	0.20%	0.20%(d)
Net investment income (loss)	0.00%(e)	0.57%	2.19%	1.95%	1.19%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.
(e)	Amount is less than 0.005%.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Premier Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0002	$1.0001	$0.9999	$0.9999	$1.0001
Income (loss) from investment operations:
Net investment income (loss)	0.0004	0.0058	0.0223	0.0199	0.0105
Net realized and unrealized gain (loss)	—	0.0001	0.0007	—	(0.0002)
Total from investment operations	0.0004	0.0059	0.0230	0.0199	0.0103
Distributions to shareholders from:
Net investment income	(0.0005)	(0.0058)	(0.0228)	(0.0199)	(0.0105)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0005)	(0.0058)	(0.0228)	(0.0199)	(0.0105)
Net asset value, end of period	$1.0001	$1.0002	$1.0001	$0.9999	$0.9999
Total return (c)	0.04%	0.59%	2.32%	2.00%	1.05%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$11,646,151	$14,854,601	$20,188,261	$9,489,591	$8,303,222
Ratios to Average Net Assets:
Total expenses	0.12%	0.12%	0.13%	0.12%	0.12%
Net expenses	0.12%	0.12%	0.12%	0.12%	0.12%
Net investment income (loss)	0.06%	0.67%	2.23%	2.00%	1.06%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Opportunity Class (a)
	For the Period 10/28/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)
Net realized and unrealized gain (loss)	(0.0001)
Total from investment operations	(0.0001)
Distributions to shareholders from:
Net investment income	(0.0000)(b)
Net asset value, end of period	$0.9999
Total return (c)	(0.01)%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(d)
Net expenses	0.15%(d)
Net investment income (loss)	0.00%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 7/31/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0038	0.0205	0.0085
Net realized gain (loss)	0.0001	—	0.0000(b)	(0.0000)(b)
Total from investment operations	0.0002	0.0038	0.0205	0.0085
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0038)	(0.0205)	(0.0085)
Net realized gains	(0.0001)	—	—	—
Total distributions	(0.0002)	(0.0038)	(0.0205)	(0.0085)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.38%	2.07%	0.85%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$911,380	$244,039	$23,628	$50
Ratios to Average Net Assets:
Total expenses	0.15%	0.15%	0.15%	0.15%(d)
Net expenses	0.06%	0.14%	0.15%	0.15%(d)
Net investment income (loss)	0.01%	0.12%	1.86%	2.01%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Administration Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 07/31/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0009	0.0029	0.0184	0.0076
Net realized gain (loss)	(0.0007)	(0.0001)	0.0000(b)	(0.0000)(b)
Total from investment operations	0.0002	0.0028	0.0184	0.0076
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0028)	(0.0184)	(0.0076)
Net realized gains	(0.0001)	—	—	—
Total distributions	(0.0002)	(0.0028)	(0.0184)	(0.0076)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.00%(d)	0.28%	1.85%	0.76%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50	$325	$50	$50
Ratios to Average Net Assets:
Total expenses	0.37%	0.37%	0.37%	0.37%(e)
Net expenses	0.07%	0.18%	0.37%	0.37%(e)
Net investment income (loss)	0.01%	0.07%	1.84%	1.79%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investment Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000	0.0027	0.0175	0.0138	0.0041
Net realized gain (loss)	0.0002	0.0001	0.0000(b)	(0.0000)(b)	0.0000(b)
Total from investment operations	0.0002	0.0028	0.0175	0.0138	0.0041
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0027)	(0.0175)	(0.0138)	(0.0041)
Net realized gains	(0.0001)	(0.0001)	—	—	(0.0000)(b)
Total distributions	(0.0002)	(0.0028)	(0.0175)	(0.0138)	(0.0041)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.27%	1.76%	1.39%	0.41%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$283,888	$479,954	$408,230	$390,735	$366,364
Ratios to Average Net Assets:
Total expenses	0.47%	0.47%	0.47%	0.47%	0.47%
Net expenses	0.06%	0.26%	0.46%	0.47%	0.47%
Net investment income (loss)	0.01%	0.21%	1.74%	1.37%	0.38%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investor Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0035	0.0200	0.0165	0.0068
Net realized gain (loss)	0.0001	—	0.0000(b)	(0.0000)(b)	0.0000(b)
Total from investment operations	0.0002	0.0035	0.0200	0.0165	0.0068
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0035)	(0.0200)	(0.0165)	(0.0068)
Net realized gains	(0.0001)	—	—	—	(0.0000)(b)
Total distributions	(0.0002)	(0.0035)	(0.0200)	(0.0165)	(0.0068)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.35%	2.02%	1.66%	0.68%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$538,275	$555,517	$131,075	$97,241	$29,583
Ratios to Average Net Assets:
Total expenses	0.20%	0.20%	0.20%	0.20%	0.20%
Net expenses	0.06%	0.17%	0.20%	0.20%	0.20%
Net investment income (loss)	0.01%	0.17%	1.95%	1.70%	0.71%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Premier Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000	0.0040	0.0208	0.0173	0.0076
Net realized gain (loss)	0.0002	0.0001	0.0000(b)	(0.0000)(b)	0.0000(b)
Total from investment operations	0.0002	0.0041	0.0208	0.0173	0.0076
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0040)	(0.0208)	(0.0173)	(0.0076)
Net realized gains	(0.0001)	(0.0001)	—	—	(0.0000)(b)
Total distributions	(0.0002)	(0.0041)	(0.0208)	(0.0173)	(0.0076)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.40%	2.10%	1.74%	0.76%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$11,700,899	$14,707,995	$11,812,916	$9,424,507	$12,123,627
Ratios to Average Net Assets:
Total expenses	0.12%	0.12%	0.12%	0.12%	0.12%
Net expenses	0.06%	0.12%	0.12%	0.12%	0.12%
Net investment income (loss)	0.01%	0.33%	2.07%	1.71%	0.76%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Opportunity Class (a)
	For the Period 10/28/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0001
Total from investment operations	0.0002
Distributions to shareholders from:
Net investment income	(0.0001)
Net realized gains	(0.0001)
Total distributions	(0.0002)
Net asset value, end of period	$1.0000
Total return (b)	0.00%(c)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(d)
Net expenses	0.05%(d)
Net investment income (loss)	0.01%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Amount is less than 0.005%.
(d)	Annualized.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 7/31/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0037	0.0207	0.0085
Net realized gain (loss)	—	—	(0.0000)(b)	—
Total from investment operations	0.0001	0.0037	0.0207	0.0085
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0037)	(0.0207)	(0.0085)
Total distributions	(0.0001)	(0.0037)	(0.0207)	(0.0085)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.02%	0.37%	2.09%	0.85%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$278,027	$90,569	$468,721	$94,554
Ratios to Average Net Assets:
Total expenses	0.15%	0.15%	0.15%	0.15%(d)
Net expenses	0.06%	0.15%	0.15%	0.15%(d)
Net investment income (loss)	0.02%	0.34%	2.09%	2.04%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Administration Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 07/31/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0027	0.0185	0.0076
Net realized gain (loss)	—	—	(0.0000)(b)	—
Total from investment operations	0.0001	0.0027	0.0185	0.0076
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0027)	(0.0185)	(0.0076)
Total distributions	(0.0001)	(0.0027)	(0.0185)	(0.0076)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.00%(d)	0.27%	1.86%	0.76%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50	$50	$50	$50
Ratios to Average Net Assets:
Total expenses	0.37%	0.36%	0.37%	0.37%(e)
Net expenses	0.07%	0.25%	0.37%	0.37%(e)
Net investment income (loss)	0.00%(d)	0.27%	1.85%	1.78%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

Table of Contents

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investment Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0025	0.0180	0.0139	0.0042
Net realized gain (loss)	—	—	(0.0000)(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0025	0.0180	0.0139	0.0042
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0025)	(0.0180)	(0.0139)	(0.0042)
Net realized gains	—	—	—	—	(0.0000)(b)
Total distributions	(0.0001)	(0.0025)	(0.0180)	(0.0139)	(0.0042)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.25%	1.81%	1.40%	0.42%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$23,688	$42,358	$52,086	$69,812	$19,242
Ratios to Average Net Assets:
Total expenses	0.47%	0.47%	0.47%	0.47%	0.47%
Net expenses	0.07%	0.29%	0.46%	0.47%	0.47%
Net investment income (loss)	0.00%(d)	0.27%	1.78%	1.54%	0.36%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investor Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0034	0.0202	0.0166	0.0069
Net realized gain (loss)	—	—	(0.0000)(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0034	0.0202	0.0166	0.0069
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0034)	(0.0202)	(0.0166)	(0.0069)
Net realized gains	—	—	—	—	(0.0000)(b)
Total distributions	(0.0001)	(0.0034)	(0.0202)	(0.0166)	(0.0069)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.34%	2.03%	1.67%	0.69%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,492,307	$546,563	$230,017	$774,885	$328,764
Ratios to Average Net Assets:
Total expenses	0.20%	0.20%	0.20%	0.20%	0.20%
Net expenses	0.07%	0.18%	0.20%	0.20%	0.20%
Net investment income (loss)	0.01%	0.31%	2.02%	1.67%	0.70%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Premier Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0040	0.0210	0.0174	0.0077
Net realized gain (loss)	—	—	(0.0000)(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0040	0.0210	0.0174	0.0077
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0040)	(0.0210)	(0.0174)	(0.0077)
Net realized gains	—	—	—	—	(0.0000)(b)
Total distributions	(0.0001)	(0.0040)	(0.0210)	(0.0174)	(0.0077)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.02%	0.40%	2.12%	1.75%	0.77%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$16,944,237	$20,004,414	$14,672,348	$8,402,049	$4,000,478
Ratios to Average Net Assets:
Total expenses	0.12%	0.12%	0.12%	0.12%	0.12%
Net expenses	0.06%	0.12%	0.12%	0.12%	0.12%
Net investment income (loss)	0.02%	0.33%	2.07%	1.80%	0.81%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Opportunity Class (a)
	For the Period 10/28/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.00%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(e)
Net expenses	0.04%(e)
Net investment income (loss)	0.00%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 1/18/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0037	0.0207	0.0170
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—
Total from investment operations	0.0001	0.0037	0.0207	0.0170
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0037)	(0.0207)	(0.0170)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.03%	0.37%	2.09%	1.67%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,588,396	$1,349,398	$950,202	$639,733
Ratios to Average Net Assets:
Total expenses	0.15%	0.15%	0.15%	0.15%(d)
Net expenses	0.04%	0.14%	0.15%	0.15%(d)
Net investment income (loss)	0.03%	0.42%	1.95%	1.71%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Administration Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0026	0.0186	0.0150	0.0054
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0026	0.0186	0.0150	0.0054
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0026)	(0.0186)	(0.0150)	(0.0054)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0026)	(0.0186)	(0.0150)	(0.0054)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.26%	1.88%	1.51%	0.54%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,230,490	$2,550,831	$1,672,762	$1,686,105	$1,909,670
Ratios to Average Net Assets:
Total expenses	0.37%	0.37%	0.37%	0.37%	0.37%
Net expenses	0.07%	0.23%	0.37%	0.37%	0.37%
Net investment income (loss)	0.01%	0.20%	1.87%	1.47%	0.50%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investment Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0025	0.0178	0.0140	0.0044
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0025	0.0178	0.0140	0.0044
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0025)	(0.0178)	(0.0140)	(0.0044)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0025)	(0.0178)	(0.0140)	(0.0044)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.25%	1.79%	1.40%	0.44%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$428,088	$483,015	$517,997	$380,085	$432,488
Ratios to Average Net Assets:
Total expenses	0.47%	0.47%	0.47%	0.47%	0.47%
Net expenses	0.07%	0.27%	0.45%	0.47%	0.47%
Net investment income (loss)	0.01%	0.32%	1.76%	1.42%	0.40%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Investor Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0033	0.0203	0.0170	0.0071
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0033	0.0203	0.0170	0.0071
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0033)	(0.0203)	(0.0170)	(0.0071)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0033)	(0.0203)	(0.0170)	(0.0071)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.33%	2.05%	1.68%	0.71%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,063,097	$936,980	$726,126	$1,875,096	$1,245,204
Ratios to Average Net Assets:
Total expenses	0.20%	0.20%	0.20%	0.20%	0.20%
Net expenses	0.07%	0.18%	0.20%	0.20%	0.20%
Net investment income (loss)	0.01%	0.35%	2.08%	1.68%	0.83%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Premier Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0039	0.0211	0.0170	0.0079
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0039	0.0211	0.0170	0.0079
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0039)	(0.0211)	(0.0170)	(0.0079)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0039)	(0.0211)	(0.0170)	(0.0079)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.03%	0.39%	2.13%	1.76%	0.79%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$84,009,144	$67,604,723	$52,826,660	$32,939,927	$38,921,503
Ratios to Average Net Assets:
Total expenses	0.12%	0.12%	0.12%	0.12%	0.12%
Net expenses	0.05%	0.12%	0.12%	0.12%	0.12%
Net investment income (loss)	0.03%	0.33%	2.08%	1.74%	0.78%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Opportunity Class (a)
	For the Period 10/28/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.00%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$300,002
Ratios to Average Net Assets:
Total expenses	0.15%(d)
Net expenses	0.04%(d)
Net investment income (loss)	0.03%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of their respective Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

MULTICLSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Institutional Liquid Reserves Fund: Service Class (LRSXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the Fund offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund may offer multiple classes of shares. This Prospectus covers only the Service Class Shares of the Fund.

The Fund is a “floating net asset value” money market fund. The share price of the Fund will fluctuate.

TABLE OF CONTENTS

Fund Summary	1
State Street Institutional Liquid Reserves Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	8
Additional Information About Non-Principal Investment Strategies and Risks	15
Portfolio Holdings Disclosure	17
Management and Organization	18
Shareholder Information	20
Dividends, Distributions and Tax Considerations	25
Financial Intermediary Arrangements	27
Financial Highlights	29

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State Street Institutional Liquid Reserves Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.12%
Total Annual Fund Operating Expenses²	0.17%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$17		$55		$96		$217

Principal Investment Strategies

The Fund follows a disciplined investment process in which SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, bases its decisions on the relative attractiveness of different money market instruments. In the Adviser's opinion, the attractiveness of an instrument may vary depending on the general level of interest

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rates, as well as imbalances of supply and demand in the market. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

Principal Risks

The Fund is subject to the following principal risks. You could lose money by investing in the Fund. Because the share price of the Fund will fluctuate, when you sell your shares, they may be worth more or less than what you originally paid for them. The Fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares if the Fund's liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

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may lock in a below-market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. Enforcing rights against the underlying assets or collateral may be difficult, and the underlying assets or collateral may be insufficient if the issuer defaults.

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countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

Performance

The bar chart and table below provide some indication of the risks of investing in the ILR Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. Performance history will be available for the Service Class shares of the Fund after they have been in operation for one calendar year. Returns of Service Class shares could have been similar to the returns shown for Premier Class shares because the shares are invested in the same portfolio of securities. Returns would differ only to the extent that Service Class shares do not have the same expenses as Premier Class shares. Service Class shares are generally expected to incur higher expenses, and so generally lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.65% (Q1, 2019)
Lowest Quarterly Return: 0.00% (Q4, 2021)

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Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.04%		1.20%		0.69%		8/12/2004

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Service Class
To establish an account	$10,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

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Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

Investment Objective

The investment objective of the Fund, as stated in the Fund Summary, may be changed without shareholder approval.

Principal Investment Strategies

The Fund follows a disciplined investment process in which SSGA FM bases its decisions on the relative attractiveness of different money market instruments. In the Adviser's opinion, the attractiveness of an instrument may vary depending on the general level of interest rates, as well as imbalances of supply and demand in the market. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

Banking Companies Risk. The performance of bank stocks may be affected by extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, and the interest rates and fees they can charge and the amount of capital they must maintain. Profitability is largely dependent on the avail-

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ability and cost of capital funds, and can fluctuate significantly when interest rates change. Credit losses resulting from financial difficulties of borrowers can negatively impact the banking companies. Banks may also be subject to severe price competition. Competition among banking companies is high and failure to maintain or increase market share may result in lost market value.

Call/Prepayment Risk. Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by the Fund earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by the Fund are prepaid. In any such case, the Fund may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Fund's income.

Counterparty Risk. The Fund will be subject to credit risk with respect to the counterparties with which the Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, the Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Credit Risk. Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by the Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by the Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when the Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

The credit rating assigned to any particular investment does not necessarily reflect the issuer's current financial condition and does not reflect an assessment of an investment's volatility or liquidity. Securities rated in the lowest category of investment-grade are considered to have speculative characteristics. If a security held by the Fund loses its rating or its rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

Debt Securities Risk. The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Extension Risk. During periods of rising interest rates, the average life of certain types of securities may be extended because of slower-than-expected principal payments. This may increase the period of time during which an investment earns a below-market interest rate, increase the security's duration and reduce the value of the security. Extension risk may be heightened during periods of adverse economic conditions generally, as payment rates decline due to higher unemployment levels and other factors.

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Income Risk. The Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by the Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by the Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by the Fund may limit the Fund's ability to achieve its objective.

Interest Rate Risk. Interest rate risk is the risk that the securities held by the Fund will decline in value because of increases in market interest rates. Duration is a measure used to determine the sensitivity of a security's price to changes in interest rates. Debt securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than debt securities with shorter durations. For example, the value of a security with a duration of five years would be expected to decrease by 5% for every 1% increase in interest rates. Falling interest rates also create the potential for a decline in the Fund's income and yield. Interest-only and principal-only securities are especially sensitive to interest rate changes, which can affect not only their prices but can also change the income flows and repayment assumptions about those investments. Variable and floating rate securities also generally increase or decrease in value in response to changes in interest rates, although generally to a lesser degree than fixed-rate securities. A substantial increase in interest rates may also have an adverse impact on the liquidity of a security, especially those with longer durations. Changes in governmental policy, including changes in central bank monetary policy, could cause interest rates to rise rapidly, or cause investors to expect a rapid rise in interest rates. This could lead to heightened levels of interest rate, volatility and liquidity risks for the fixed income markets generally and could have a substantial and immediate effect on the values of the Fund's investments.

Large Shareholder Risk. To the extent a large proportion of the interests of the Portfolio are highly concentrated or held by a small number of investors (or a single investor), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these investors will purchase or redeem Portfolio interests in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program. For example, they could require the Portfolio to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to investors, or the Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case the Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. The Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Liquidity Risk. Liquidity risk is the risk that the Fund may not be able to dispose of investments readily at a favorable time or prices (or at all) or at prices approximating those at which the Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for the Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. The Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity the Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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Low Short-Term Interest Rate Risk. During market conditions in which short-term interest rates are at low levels the Fund's yield can be very low. During these conditions, it is possible that the Fund will generate an insufficient amount of income to pay its expenses, and that it will not be able to pay a daily dividend and may have a negative yield (i.e., it may lose money on an operating basis). It is possible that the Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income.

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edented actions to support local and global economies and the financial markets. The impact of these measures, and whether they will be effective to mitigate the economic and market disruption, will not be known for some time. The foregoing could result in disruptions to the services provided to the Fund by its service providers.

Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Master/Feeder Structure Risk. The Fund pursues its objective by investing substantially all of its assets in another pooled investment vehicle (a “master fund”). The ability of the Fund to meet its investment objective is directly related to the ability of the master fund to meet its investment objective. The ability of the Fund to meet its objective may be adversely affected by the purchase and redemption activities of other investors in the master fund. The ability of the Fund to meet redemption requests will depend on its ability to redeem its interest in the master fund. The Adviser or an affiliate serves as investment adviser to the master fund, leading to potential conflicts of interest. For example, the Adviser or its affiliates will receive fees based on the amount of assets invested in the master fund. Investment by the Fund in the master fund may be beneficial in the management of the master fund, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest the Fund's assets in a master fund sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in such master fund over a master fund sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by the Fund in a master fund sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a master fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so. The Fund will bear its pro rata portion of the expenses incurred by the master fund.

Money Market Risk-Floating NAV. The Fund does not maintain a constant net asset value per share. The value of the Fund's Shares is calculated to four decimal places and will vary reflecting the value of the portfolio of investments held by the Fund. It is possible to lose money by investing in the Fund.

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related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which the Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Non-U.S. Securities Risk. Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect the Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of the Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where the Fund invests could cause the Fund's investments in that country to experience gains or losses.

Rapid Changes in Interest Rates. The values of instruments held by the Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause the Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses would negatively affect the NAV per share of the Fund.

Reinvestment Risk. Income from the Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing the Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by the Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

Repurchase Agreement Risk. A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by the Fund which are collateralized by the securities subject to repurchase. The Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If the Fund's counterparty should default on its obligations and the Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, the Fund may realize a loss.

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Restricted Securities Risk. The Fund may hold securities that have not been registered for sale to the public under the U.S. federal securities laws pursuant to an exemption from registration. These securities may be less liquid than securities registered for sale to the general public. The liquidity of a restricted security may be affected by a number of factors, including, among others: (i) the creditworthiness of the issuer; (ii) the frequency of trades and quotes for the security; (iii) the number of dealers willing to purchase or sell the security and the number of other potential purchasers; (iv) dealer undertakings to make a market in the security; (v) the nature of any legal restrictions governing trading in the security; and (vi) the nature of the security and the nature of marketplace trades. There can be no assurance that a liquid trading market will exist at any time for any particular restricted security. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

Risks Related to ECDs, ETDs and YCDs. Banks issuing ECDs, ETDs and YCDs are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of foreign issuers also involve risks such as future unfavorable political and economic developments, withholding or other tax, seizures of foreign deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

Section 4(a)(2) Commercial Paper and Rule 144A Securities Risk. The Fund may invest in commercial paper issued in reliance on the private placement exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the “1933 Act”). This commercial paper is commonly called “Section 4(a)(2) paper.” The Fund may also invest in securities that may be offered and sold only to “qualified institutional buyers” under Rule 144A of the 1933 Act (“Rule 144A securities”).

Section 4(a)(2) paper is sold to institutional investors who must agree to purchase the paper for investment and not with a view to public distribution. Any resale by the purchaser must be in a transaction exempt from the registration requirements of the 1933 Act. Section 4(a)(2) paper normally is resold to other institutional investors like the Fund through or with the assistance of the issuer or investment dealers that make a market in Section 4(a)(2) paper. As a result, it suffers from liquidity risk, the risk that the securities may be difficult to value because of the absence of an active market and the risk that it may be sold only after considerable expense and delay, if at all. Rule 144A securities generally must be sold only to other qualified institutional buyers.

Section 4(a)(2) paper and Rule 144A securities will not be considered illiquid for purposes of the Fund's limitation on illiquid securities if the Adviser (pursuant to guidelines adopted by the Board) determines that a liquid trading market exists for the securities in question. There can be no assurance that a liquid trading market will exist at any time for any particular Section 4(a)(2) paper or Rule 144A securities.

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U.S. Government Securities Risk. U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor supported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of the Fund's investments.

Variable and Floating Rate Securities Risk. Variable or floating rate securities are debt securities with variable or floating interest rates payments. Variable or floating rate securities bear rates of interest that are adjusted periodically according to formulae intended generally to reflect market rates of interest and allow the Fund to participate (determined in accordance with the terms of the securities) in increases in interest rates through upward adjustments of the coupon rates on the securities. However, during periods of increasing interest rates, changes in the coupon rates may lag behind the changes in market rates or may have limits on the maximum increases in coupon rates. Alternatively, during periods of declining interest rates, the coupon rates on such securities will typically readjust downward resulting in a lower yield. The Fund may also invest in variable or floating rate equity securities, whose dividend payments vary based on changes in market rates of interest or other factors.

Zero-Coupon Bond Risk. Zero-coupon bonds are debt obligations that are generally issued at a discount and payable in full at maturity, and that do not provide for current payments of interest prior to maturity. Zero-coupon bonds usually trade at a deep discount from their face or par values and are subject to greater market value fluctuations from changing interest rates than debt obligations of comparable maturities that make current distributions of interest. When interest rates rise, the values of zero-coupon bonds fall more rapidly than securities paying interest on a current basis, because the Fund is unable to reinvest interest payments at the higher rates.

Additional Information About Non-Principal Investment Strategies and Risks

The investments described below reflect the Fund's and the Portfolio's current practices. In addition to the principal risks described above, other risks are described in some of the descriptions of the investments below:

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chase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

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Temporary Defensive Positions. In response to actual or perceived adverse market, economic, political, or other conditions, the Fund may (but will not necessarily), without notice, depart from its principal investment strategies by temporarily investing for defensive purposes. While investing defensively, the Fund may maintain a substantial portion of its assets in cash, on which the Fund may earn little if any income. If the Fund invests for defensive purposes, it may not achieve its investment objective. In addition, the defensive strategy may not work as intended.

Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

The Fund can withdraw its investment in the Portfolio if, at any time, the Fund's Board of Trustees (the “Board”) determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives of the Portfolio changed so that they were inconsistent with the objectives of the Fund. If the Fund withdraws its investment from the Portfolio, the Fund may invest all of its assets in another mutual fund that has the same investment objective as the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and Portfolio and, subject to the oversight of the Board, is responsible for the investment management of the Fund. The Adviser provides an investment management program for the Fund and manages the investment of the Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the SEC under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

The Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from the Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolio's investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.05% for the Money Market Portfolio.

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund is contractually obligated, through April 30, 2023 (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.07% of average daily net assets on an annual basis (the “Total Annual Fund Operating Expense Waiver”). The Total Annual Fund Operating Expense Waiver may not be terminated prior to April 30, 2023 with respect to the Fund except with approval of the Fund's Board of Trustees.

In addition to any contractual expense limitation for the Fund which is described in the Fund Summary, each of the Adviser and State Street Global Advisors Funds Distributors, LLC (each a “Service Provider”) also may voluntarily reduce all or a portion of its fees and/or reimburse expenses for the Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”). Under an agreement with the Service Providers relating to the Voluntary Reduction, the Fund and the Portfolio have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund.

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A reimbursement to the Service Provider would increase fund expenses and may negatively impact the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield. The Fund has agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. The Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one‑day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b‑1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of the Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

SSGA FD serves as the Fund's shareholder servicing agent pursuant to the Shareholder Servicing Agreement between SSGA FD and the Trust and receives fees from the Fund for the provision and procurement of applicable services. Please see the SAI for more information on SSGA FD's role as the Fund's shareholder servicing agent.

Additional Information

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Shareholder Information

Determination of Net Asset Value

The Fund determines its NAV per share three times each day on which the New York Stock Exchange (the “NYSE”), the Federal Reserve banks and State Street are open for business (a “Business Day”) at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The price for Fund shares is the NAV next calculated after the purchase order is accepted by a Fund. Orders accepted before 12:00 p.m. will receive the 12:00 p.m. NAV, orders accepted before 3:00 p.m. will receive the 3:00 p.m. NAV, and orders accepted after 3:00 p.m. will receive 8:00 a.m. NAV calculated on the following Business Day. The Fund calculates its NAV to four decimal places.

The NAV of each class of the Fund's shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding. The Fund values each security or other investment pursuant to guidelines adopted by the Board of Trustees. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent that the Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Pricing does not occur on NYSE holidays. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. The Fund reserves the right to accept orders to purchase or redeem shares, or to continue to accept such orders following the close of the NYSE, on any day that is not a Business Day or any day on which the NYSE closes early, provided the Federal Reserve remains open. As noted in this Prospectus, the Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when the Fund does not price its shares. Consequently, the NAV of the Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's shares. The Fund also may establish special hours on those days to determine the Fund's NAV. In the event that the Fund invokes the right to accept orders to purchase or redeem shares on any day that is not a Business Day or adopt special hours of operation, the Fund will post advance notice of these events at:www.ssga.com/cash.

If you hold shares of the Fund through a broker-dealer or other financial intermediary, your intermediary may offer additional services and account features that are not described in this Prospectus. Please contact your intermediary directly for an explanation of these services.

Investing in State Street Institutional Investment Trust Shares

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advance notice to shareholders. Please call or check online for current information. Requests for transactions in the State Street Funds will be processed when they are received in “good order.” “Good order” means that the request is in an accurate and complete form, and all applicable documents have been received in such accurate and complete form (including, typically, a signed application and medallion-guaranteed documents), and, for a purchase request, the check or wired funds have cleared.

Purchasing Shares

Investors pay no sales load to invest in the Service Class Shares of the Fund. Purchase requests received by the Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Times (for the Fund generally, 3:00 p.m. ET, unless the Fund closes earlier) will earn dividend accrual for that purchase.

The minimum initial investment in Service Class of the Fund is $10 million, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include, but are not limited to, accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Fund and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below).

All purchases that are made by check will be priced with the last valuation price and begin earning dividends the following Business Day after the day the order is accepted. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) All purchase orders are subject to acceptance by the Fund. The Fund intends to be as fully invested as is practicable; therefore, investments must be made in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank).

The Fund reserves the right to cease accepting investments at any time or to reject any investment order. The Fund determines its NAV at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The 8:00 a.m., 12:00 p.m. and 3:00 p.m. NAV calculation times are intended to facilitate same day settlement.

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How to Purchase Shares

By Mail:

An initial investment in the Fund must be preceded or accompanied by a completed, signed Institutional Account Application Form, sent to:
State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

An initial investment in the Fund must be preceded or accompanied by a completed, signed Institutional Account Application Form, faxed to (816) 218-0400. Call the Fund at (866) 392-0869 between the hours of 7:00 a.m. ET and 5:00 p.m. ET to:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Fund and the Fund's agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after the Fund receives a redemption order in good form.

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pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). The Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

Certain special limitations affecting redemptions. The SEC has implemented a number of requirements, including liquidity fees and redemption gates, for money market funds based on the amount of fund assets in “weekly liquid assets,” which generally includes cash, direct obligations of the U.S. government, certain other U.S. government or agency securities, and securities that will mature or are subject to a demand feature that is exercisable and payable within five Business Days. The ILR Fund will pass through to its investors any liquidity fee or suspension of redemptions imposed by the Money Market Portfolio on the same terms and conditions as imposed by the Money Market Portfolio on the ILR Fund.

If the Money Market Portfolio's weekly liquid assets fall below 30% of its total assets and the Portfolio's Board of Trustees determines it is in the best interests of the Portfolio, the Portfolio may immediately impose a liquidity fee of no more than 2% and/or temporarily suspend redemptions for up to 10 Business Days in any 90 day period. If the Portfolio's weekly liquid assets fall below 10% of its total assets at the end of any Business Day, the Portfolio will impose a liquidity fee of 1% on all redemptions beginning on the next Business Day, unless the Portfolio's Board determines that imposing such a fee would not be in the best interests of the Portfolio or determines that a lower or higher fee (not to exceed 2%) would be in the best interests of the Portfolio, which would remain in effect until weekly liquid assets return to 30% or the Portfolio's Board determines that the fee is no longer in the best interests of the Portfolio. All liquidity fees payable by the ILR Fund would be passed through to its shareholders, would be payable to the Portfolio and could offset any losses realized by the Portfolio when seeking to honor redemption requests. If liquidity fees are imposed or redemptions are suspended by the Portfolio, the ILR Fund will notify shareholders on the ILR Fund's website. The ILR Fund expects to treat such liquidity fees paid to the Portfolio as reducing proceeds paid to shareholders in redemption of ILR Fund shares, and not constituting income to the Portfolio or the Fund. There may be circumstances under which the ILR Fund may impose its own liquidity fees and/or suspend redemptions based on the level of the ILR Fund's own weekly liquid assets, in which case the ILR Fund will also provide notice to shareholders.

If the Money Market Portfolio's weekly liquid assets fall below 10% of its assets on a Business Day, the Portfolio may cease honoring redemptions and liquidate in the discretion of the Portfolio's Board. If the ILR Fund is notified that its Portfolio's weekly liquid assets fall below 10% of the Portfolio's assets and the Portfolio has suspended redemptions and intends to liquidate, the ILR Fund may also do so in the discretion of the ILR Fund's Board. There may be circumstances under which the ILR Fund may cease honoring redemptions and liquidate in the discretion of its Board based on the level of the ILR Fund's own weekly liquid assets. If the ILR Fund ceases honoring redemptions and determines to liquidate, the ILR Fund expects that it would notify shareholders on the ILR Fund's website. Distributions to shareholders of liquidation proceeds may occur in one or more disbursements.

The right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed beyond 7 days in accordance with Section 22(e) of the 1940 Act and the rules thereunder, including during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or if an emergency exists as a result of which disposal by the Fund of securities owned by it is not reasonably practicable or it is not reasonably practicable for the Fund fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of shareholders of the Fund. The Fund also may permanently suspend redemptions and liquidate if, among other reasons, (i) the Fund, at the end of a business day, has invested less than 10% of its total assets in weekly liquid assets and (ii) the Board, including the Independent Trustees, irrevocably has approved the liquidation of the Fund.

The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

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During periods of deteriorating or stressed market conditions or during extraordinary or emergency circumstances, the Fund may be more likely to pay redemption proceeds with cash obtained through short-term borrowing arrangements (if available) or by giving you securities.

A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Fund reserves the right to modify minimum account requirements at any time with or without prior notice. The Fund also reserves the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Fund will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Fund calculates its NAVs earlier than normal, the Fund reserves the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Fund reserves the right to waive medallion guarantee requirements, require a medallion guarantee under other circumstances or reject or delay redemption if the medallion guarantee is not in good form. Medallion guarantees may be provided by an eligible financial institution such as a commercial bank, a Financial Industry Regulatory Authority, Inc. (“FINRA”) member firm such as a stock broker, a savings association or a national securities exchange. A notary public cannot provide a medallion guarantee. The Fund reserves the right to reject a medallion guarantee if it is not provided by a STAMP Medallion guarantor.

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promptly notifying the Fund of any errors or inaccuracies, including, without limitation, any errors or inaccuracies relating to shareholder data or information transmitted by telephone. During periods of heavy market activity or other times, it may be difficult to reach the Fund by telephone. If you are unable to reach us by telephone, consider sending written instructions.

The Fund may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and the Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Excessive Trading

Because the Fund is a money market fund, the Fund's Board has not adopted policies and procedures with respect to frequent purchases and redemptions of Fund shares by Fund shareholders. Nonetheless, the Fund may take any reasonable action that it deems necessary or appropriate to prevent excessive trading in Fund shares without providing prior notification to the account holder. Such action may include rejecting any purchase, in whole or part, including, without limitation, by a person whose trading activity in Fund shares may be deemed harmful to the Fund. While the Fund attempts to discourage such excessive trading, there can be no guarantee that it will be able to identify investors who are engaging in excessive trading or limit their trading practices. Additionally, frequent trades of small amounts may not be detected. The Fund recognizes that it may not always be able to detect or prevent excessive trading or other activity that may disadvantage the Fund or its shareholders.

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Fund's Prospectus and the annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

The Fund intends to declare dividends on shares from net investment income daily and pay them as of the last Business Day of each month. Distributions from capital gains, if any, will be made annually in December. Dividends of investment income and capital gain distributions will be paid in additional shares on the reinvestment date unless you have elected to receive them in cash. No interest will accrue on the amounts represented by uncashed distribution checks. If you have elected to receive distributions by check, and the postal or other delivery service is unable to deliver the checks because of an incorrect mailing address, or if a distribution check remains uncashed for six months, the uncashed distribution and all future distributions will be reinvested at the then-current NAV of the Fund.

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The Fund invests substantially all of its investable assets in the Portfolio which is treated as a partnership for U.S. federal income tax purposes. Therefore, the nature and character of the Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and the Fund will be allocated its share of the Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of the Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of the Fund will be to the Fund's allocable share of the assets of the Portfolio.

Distributions are taxable to you even if they are paid from income or gains earned by the Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

The Fund's and Portfolio's income from or proceeds of investments in non-U.S. assets may be subject to non-U.S. withholding and other taxes. This will decrease the Fund's return on securities subject to such taxes. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes. Although such taxes will reduce the Fund's taxable income, shareholders generally will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Portfolio or Fund.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund and net gains recognized on the redemption of Fund Shares.

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Financial Intermediary Arrangements

Payments to Financial Intermediaries

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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transmits the order in good form and in a timely manner to the applicable State Street Fund(s). For the ILR Fund, the State Street Funds will be the sole party to determine if a trade is received in good order. The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to the Fund.

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Financial Highlights

The Service Class shares of the Fund had not commenced operations prior to the date of this Prospectus and therefore do not have financial information.

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments will be available in the Fund's most recent annual and semi-annual reports to shareholders. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports will be available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, or will be available, free of charge, on the Fund's website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

MULTISVSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Aggregate Bond Index Portfolio (SSAFX)

State Street Equity 500 Index II Portfolio (SSEYX)

State Street Global All Cap Equity ex-U.S. Index Portfolio (SSGVX)

State Street Small/Mid Cap Equity Index Portfolio (SSMHX)

An investment in any of the Portfolios offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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Fund Summaries	1
State Street Aggregate Bond Index Portfolio	1
State Street Equity 500 Index II Portfolio	8
State Street Global All Cap Equity ex-U.S. Index Portfolio	14
State Street Small/Mid Cap Equity Index Portfolio	22
Additional Information About Investment Objectives, Principal Strategies and Risks	29
Additional Information About Non-Principal Investment Strategies and Risks	47
Portfolio Holdings Disclosure	49
Management and Organization	50
Shareholder Information	53
Dividends, Distributions and Tax Considerations	55
Financial Highlights	58
Index/Trademark Licenses/Disclaimers	63

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State Street Aggregate Bond Index Portfolio

Investment Objective

The State Street Aggregate Bond Index Portfolio (the “Aggregate Bond Index Portfolio” or the “Portfolio”) seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the U.S. dollar denominated investment grade bond market over the long term.

Fees and Expenses of the Portfolio

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Aggregate Bond Index Portfolio (“Portfolio Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. The Portfolio's shares are offered exclusively to investors that pay fees to SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the Portfolio's investment adviser, or its affiliates; the Portfolio pays no management fee to SSGA FM, as shown in the table below.

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.000%
Distribution and/or Shareholder Service (12b-1) Fees	0.000%
Other Expenses	0.022%
Acquired Fund Fees and Expenses	0.008%
Total Annual Fund Operating Expenses	0.030%
Less Fee Waivers and/or Expense Reimbursements^1,2	(0.008%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.022%

The Portfolio's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023, separately with respect to each of the Fund and the Portfolio, (i) to waive up to the full amount of the advisory fee payable by the Fund or the Portfolio, and/or (ii) to reimburse the Fund or the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.025% of the Fund's or the Portfolio's average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund/Portfolio's Board of Trustees.

Example:

This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated, and then sell or hold all of your Portfolio Shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 year		3 years		5 years		10 years
$2		$9		$16		$38

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Portfolio Turnover:

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 21% of the average value of its portfolio.

Principal Investment Strategies

The Portfolio is an “index” fund that seeks to track, before fees and expenses, the total return performance of the Bloomberg U.S. Aggregate Bond Index (the “U.S. Aggregate Bond Index” or sometimes referred to in context as the “Index”) over the long term. As an “index” fund, the Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment.

Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in securities that the Adviser determines have economic characteristics that are comparable to the economic characteristics of securities that comprise the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Portfolio will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. The Portfolio may also invest in other debt securities, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Portfolio may at times purchase or sell futures contracts on fixed-income securities, or options on those futures, in lieu of investing directly in fixed-income securities themselves. The Portfolio may also purchase or sell futures contracts and related options on the Index (or other fixed-income securities indices). The Portfolio might do so, for example, in order to adjust the interest-rate sensitivity of the Portfolio to bring the characteristics of the Portfolio more closely in line with those of the Index. It might also do so to increase its investment exposure pending investment of cash in bonds or other investments or to reduce its investment exposure in situations where it intends to sell a portion of the securities in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Portfolio may, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

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The Portfolio expects typically to invest a significant portion of its assets in U.S. agency mortgage pass-through securities up to a total weight that is comparable to that of the Index. Most transactions in mortgage pass-through securities occur through standardized contracts for future delivery in which the exact mortgage pools to be delivered are not specified until a few days prior to settlement, referred to as a “to-be-announced transaction” or “TBA Transaction.” In a TBA Transaction, the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to the settlement date; however, it is not anticipated that the Portfolio will receive pools, but instead will participate in rolling TBA Transactions. The Portfolio expects to enter into such contracts on a regular basis.

The Index is sponsored by Bloomberg Index Services Limited (the “Index Provider”) which is not affiliated with the Portfolio or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks of investing in the Portfolio

The Portfolio is subject to the following principal risks. You could lose money by investing in the Portfolio. Certain risks relating to instruments and strategies used in the management of the Portfolio are placed first. The significance of any specific risk to an investment in the Portfolio will vary over time, depending on the composition of the Portfolio's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Portfolio. An investment in the Portfolio is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Portfolio may not achieve its investment objective. The Portfolio is not intended to be a complete investment program, but rather is intended for investment as part of a diversified investment portfolio. Investors should consult their own advisers as to the role of the Portfolio in their overall investment programs.

Market Risk: The Portfolio's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Portfolio is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Portfolio and its investments.

Debt Securities Risk: The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Portfolio's fixed income securities to decrease, an adverse impact on the liquidity of the Portfolio's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Portfolio's yield can be low, and the Portfolio may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Portfolio may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

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Mortgage-Related and Other Asset-Backed Securities Risk: Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed-income investments. The liquidity of mortgage-related and asset-backed securities may change over time. During periods of falling interest rates, mortgage- and asset-backed securities may be called or prepaid, which may result in the Portfolio having to reinvest proceeds in other investments at a lower interest rate. During periods of rising interest rates, the average life of mortgage- and asset-backed securities may extend, which may lock in a below-market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. Enforcing rights against the underlying assets or collateral may be difficult, and the underlying assets or collateral may be insufficient if the issuer defaults.

Indexing Strategy/Index Tracking Risk: The Portfolio is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. As a result, the Portfolio's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index and, consequently, the performance, volatility, and risk of the Portfolio. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Portfolio's return may not match the return of the Index. The Portfolio incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Portfolio may not be fully invested at times, generally as a result of cash flows into or out of the Portfolio or reserves of cash held by the Portfolio to meet redemptions. The Adviser may attempt to replicate the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Portfolio's return and that of the Index.

Counterparty Risk: The Portfolio will be subject to credit risk with respect to the counterparties with which the Portfolio enters into derivatives contracts, repurchase agreements, reverse repurchase agreements, and other transactions. If a counterparty fails to meet its contractual obligations, the Portfolio may be unable to terminate or realize any gain on the investment or transaction, or to recover collateral posted to the counterparty, resulting in a loss to the Portfolio. If the Portfolio holds collateral posted by its counterparty, it may be delayed or prevented from realizing on the collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Derivatives Risk: Derivative transactions can create investment leverage and may have significant volatility. It is possible that a derivative transaction will result in a much greater loss than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Portfolio may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Portfolio's margin, or otherwise honor its obligations. A derivatives transaction may not behave in the manner anticipated by the Adviser or may not have the effect on the Portfolio anticipated by the Adviser.

Income Risk: The Portfolio's income may decline due to falling interest rates or other factors. Issuers of securities held by the Portfolio may call or redeem the securities during periods of falling interest rates, and the Portfolio would likely be required to reinvest in securities paying lower interest rates. If an obligation held by the Portfolio is prepaid, the Portfolio may have to reinvest the prepayment in other obligations paying income at lower rates.

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amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program.

Liquidity Risk: Lack of a ready market, stressed market conditions, or restrictions on resale may limit the ability of the Portfolio to sell a security at an advantageous time or price or at all. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. Illiquidity of the Portfolio's holdings may also limit the ability of the Portfolio to obtain cash to meet redemptions on a timely basis. In addition, the Portfolio, due to limitations on investments in any illiquid securities and/or the difficulty in purchasing and selling such investments, may be unable to achieve its desired level of exposure to a certain market or sector.

Risk of Investment in Other Pools: If the Portfolio invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected and is exposed indirectly to all of the risks applicable to an investment in such other pool. The investment policies of the other pool may not be the same as those of the Portfolio; as a result, an investment in the other pool may be subject to additional or different risks than those to which the Portfolio is typically subject. The Portfolio bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Portfolio may invest, leading to potential conflicts of interest. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Portfolio does so.

Unconstrained Sector Risk: The Portfolio may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. Greater investment focus on one or more sectors or industries increases the potential for volatility and the risk that events negatively affecting such sectors or industries could reduce returns, potentially causing the value of the Portfolio's Shares to decrease, perhaps significantly.

Valuation Risk: Some portfolio holdings, potentially a large portion of the Portfolio's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. In addition, there is no assurance that the Portfolio could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Portfolio would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Portfolio at that time. Investors who purchase or redeem Portfolio Shares on days when the Portfolio is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Portfolio had not fair-valued the holding(s) or had used a different valuation methodology.

When-Issued, TBA and Delayed Delivery Securities Risk: The Portfolio may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Portfolio's net asset value. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Portfolio to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Portfolio by illustrating the variability of the Portfolio's returns from year-to-year and by showing how the Portfolio's average annual returns for the periods indicated compared with those of the Index. The Portfolio's past performance does not necessarily indicate how the Portfolio will perform in the future. Current performance information for the Portfolio is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 3.21% (Q1, 2020)
Lowest Quarterly Return: -3.47% (Q1, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class				9/18/2014
Return Before Taxes	-1.72%	3.53%	3.12%
Return After Taxes on Distributions	-2.47%	2.44%	2.01%
Return After Taxes on Distributions and Sale of Fund Shares	-1.02%	2.25%	1.90%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)	-1.54%	3.57%	3.17%

The Portfolio will make updated performance information, including its current net asset value, available at the Portfolio's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio are Marc DiCosimo and Joanna Madden. They have served as portfolio managers of the Portfolio since 2014 and 2016, respectively.

Marc DiCosimo, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Fixed Income Beta Solutions Group. He joined the Adviser in 2013.

Joanna Madden is a Vice President of the Adviser and a Portfolio Manager in the Fixed Income Beta Solutions Group. She joined the Adviser in 2003.

Purchase and Sale of Portfolio Shares

Generally, shares of the Portfolio may be purchased only by or on behalf of other registered investment companies or private clients that compensate the Adviser or its affiliates directly.

Purchase Minimums

To establish an account	None
To add to an existing account	None

You may purchase or redeem Portfolio Shares on any day the Portfolio is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Portfolio Shares by written request or wire transfer.

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Written requests should be sent to:

By Mail:

State Street Corporation
Attention: Transfer Agent
Box 5493
Mail Code: OHD0100
North Quincy, MA 02171

By Overnight:

State Street Corporation
Attention: Transfer Agent
1 Heritage Drive
North Quincy, MA 02171

By Intermediary:

If you wish to purchase or redeem Portfolio Shares through a broker, bank or other financial intermediary (“Financial Intermediary”), please contact that Financial Intermediary directly. Your Financial Intermediary may have different or additional requirements for opening an account and/or for the processing of purchase and redemption orders, or may be closed at times when the Portfolio is open.

Financial Intermediaries may contact State Street Dealer Services Group at 617-662-7300 or email them at broker-dealerservices@statestreet.com with questions.

Tax Information

The Portfolio's distributions are expected to be taxed as ordinary income and/or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or IRA. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Portfolio Shares through a broker-dealer or other Financial Intermediary (such as a bank), the Adviser or its affiliates may pay the Financial Intermediary for certain activities related to the Portfolio, including educational training programs, conferences, the development of technology platforms and reporting systems, or other services related to the sale or promotion of the Portfolio. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Portfolio over another investment. Ask your salesperson or visit your Financial Intermediary's website for more information.

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State Street Equity 500 Index II Portfolio

Investment Objective

The State Street Equity 500 Index II Portfolio (the “Equity 500 Index II Portfolio” or the “Portfolio”) seeks to provide investment results that, before expenses, correspond generally to the total return of the S&P 500^® Index (the “S&P 500” or sometimes referred to in context as the “Index”).

Fees and Expenses of the Portfolio

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Equity 500 Index II Portfolio (“Portfolio Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. The Portfolio's shares are offered exclusively to investors that pay fees to SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the Portfolio's investment adviser, or its affiliates; the Portfolio pays no management fee to SSGA FM, as shown in the table below.

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.00%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.02%
Total Annual Fund Operating Expenses	0.02%

Example:

1 year		3 years		5 years		10 years
$2		$6		$11		$26

Portfolio Turnover:

Principal Investment Strategies

The Portfolio uses a passive management strategy designed to track the performance of the S&P 500. The Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the U.S. equities market. As of February 28, 2022, a significant portion of the Index comprised companies in the Information Technology, Health Care and Consumer Discretionary sectors, although this may change from time to time.

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The Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. Instead, the Portfolio, using a “passive” or “indexing” investment approach, seeks to provide investment results that, before expenses, correspond generally to the total return of the S&P 500.

The Portfolio generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Portfolio may purchase a sample of the stocks in the Index in proportions expected by SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Portfolio, to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Portfolio may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in securities that the Adviser determines have economic characteristics that are comparable to the economic characteristics of securities that comprise the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. In addition, the Portfolio may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Portfolio may at times purchase or sell futures contracts, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Portfolio might do so, for example, in order to increase its investment exposure pending investment of cash in the stocks comprising the Index. Alternatively, the Portfolio might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Portfolio may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

Principal Risks of investing in the Portfolio

Equity Investing Risk: The market prices of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer and also may decline due to general industry or market conditions that are not specifically related to a particular company. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

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Information Technology Sector Risk: Market or economic factors impacting information technology companies could have a major effect on the value of the Portfolio's investments. The value of stocks of information technology companies is particularly vulnerable to rapid changes in technology product cycles, rapid product obsolescence, government regulation and competition, both domestically and internationally, including competition from foreign competitors with lower production costs. Like other technology companies, information technology companies may have limited product lines, markets, financial resources or personnel. Stocks of technology companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Information technology companies are heavily dependent on patent and intellectual property rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

Derivatives Risk: Derivative transactions can create investment leverage and may have significant volatility. It is possible that a derivative transaction will result in a much greater loss than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Portfolio may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Portfolio's margin, or otherwise honor its obligations. A derivatives transaction may not behave in the manner anticipated by the Adviser or may not have the effect on the Portfolio anticipated by the Adviser.

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the health care sector require significant research and development and may be subject to regulatory approvals, all of which may be time consuming and costly with no guarantee that any product will come to market.

Large Shareholder Risk: To the extent a large proportion of the shares of the Portfolio are held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio Shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program.

Performance

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 20.51% (Q2, 2020)
Lowest Quarterly Return: -19.59% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

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	One Year	Five Years	Since Inception	Inception Date
Class				8/11/2014
Return Before Taxes	28.52%	18.36%	15.10%
Return After Taxes on Distributions	27.46%	16.89%	13.74%
Return After Taxes on Distributions and Sale of Fund Shares	17.10%	14.23%	11.76%
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.17%

The Portfolio will make updated performance information, including its current net asset value, available at the Portfolio's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio are Michael Feehily, Karl Schneider and Amy Scofield each of which has served as a portfolio manager of the Portfolio since inception in 2014.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

Amy Scofield is a Principal of the Adviser and a Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2010.

Purchase and Sale of Portfolio Shares

Generally, shares of the Portfolio may be purchased only by or on behalf of other registered investment companies or private clients that compensate the Adviser or its affiliates directly.

Purchase Minimums

To establish an account	None
To add to an existing account	None

You may purchase or redeem Portfolio Shares on any day the Portfolio is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Portfolio Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Corporation
Attention: Transfer Agent
Box 5493
Mail Code: OHD0100
North Quincy, MA 02171

By Overnight:

State Street Corporation
Attention: Transfer Agent
1 Heritage Drive
North Quincy, MA 02171

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By Intermediary:

Financial Intermediaries may contact State Street Dealer Services Group at 617-662-7300 or email them at broker-dealerservices@statestreet.com with questions.

Tax Information

The Portfolio's distributions are expected to be taxed as ordinary income, qualified dividend income and/or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or IRA. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Global All Cap Equity ex-U.S. Index Portfolio

Investment Objective

The State Street Global All Cap Equity ex-U.S. Index Portfolio (the “Global All Cap Equity ex-U.S. Index Portfolio” or the “Portfolio”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of a broad-based index of world (ex-U.S.) equity markets over the long term.

Fees and Expenses of the Portfolio

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Global All Cap Equity ex-U.S. Index Portfolio (“Portfolio Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. The Portfolio's shares are offered exclusively to investors that pay fees to SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the Portfolio's investment adviser, or its affiliates; the Portfolio pays no management fee to SSGA FM, as shown in the table below.

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.00%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.05%
Total Annual Fund Operating Expenses	0.05%

Example:

1 year		3 years		5 years		10 years
$5		$16		$28		$64

Portfolio Turnover:

Principal Investment Strategies

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financial sector, although this may change from time to time. As of February 28, 2022, a significant portion of the Index comprised companies located in Japan and the United Kingdom and a significant portion of the Index constituents are denominated in the Euro, Yen and the Pound Sterling although this may change from time to time.

In seeking to track the performance of the Index, the Portfolio employs a sampling strategy, which means that the Portfolio is not required to purchase all of the securities represented in the Index. Instead, the Portfolio may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Portfolio will be based on a number of factors, including asset size of the Portfolio. SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Portfolio, generally expects the Portfolio to hold fewer than the total number of securities in the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Portfolio's investment objective.

Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) providing exposure to securities comprising the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Portfolio will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. In addition, the Portfolio may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Portfolio may also purchase or sell futures contracts, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Portfolio might do so, for example, in order to increase its investment exposure pending investment of cash in stocks or other investments. Alternatively, the Portfolio might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options, forwards or swap transactions, in lieu of investing directly in the stocks making up the Index. The Portfolio may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

The Index is sponsored by MSCI Inc. (the “Index Provider”), which is not affiliated with the Portfolio or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks of investing in the Portfolio

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Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent the Portfolio buys securities denominated in a foreign currency, there are special risks such as changes in currency exchange rates and the risk that a foreign government could regulate foreign exchange transactions. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Portfolio. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

Europe: Developed and emerging market countries in Europe will be significantly affected by the fiscal and monetary controls of the Economic and Monetary Union of the European Union (“EU”). Changes in regulations on trade, decreasing imports or exports, changes in the exchange rate of the euro and recessions among European countries may have a significant adverse effect on the economies of other European countries. In addition, one or more countries may abandon the euro and/or withdraw from the EU For example, on January 31, 2020, the United Kingdom formally withdrew from the EU (commonly referred to as “Brexit”) and, after a transition period, left the EU single market and customs union under the terms of a new trade agreement on December 31, 2020. The agreement governs the new relationship between the United Kingdom and EU with respect to trading goods and services, but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. The full scope and nature of the consequences of the exit are not at this time known and are unlikely to be known for a significant period of time. It is also unknown whether the United Kingdom's exit will increase the likelihood of other countries also departing the EU Any exits from the EU, or the possibility of such exits, may have a significant impact on the United Kingdom, Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for such economies that could potentially have an adverse effect on the value of the Portfolio's investments. In addition, a number of countries in Europe have suffered terrorist attacks and additional attacks may occur in the future. Such attacks may cause uncertainty in financial markets and may adversely affect the performance of the issuers to which the Portfolio has exposure.

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of its trading partners. China has become an important trading partner with Japan, yet the countries' political relationship has become strained. Should political tension increase, it could adversely affect the economy, especially the export sector, and destabilize the region as a whole. Japan also remains heavily dependent on oil imports, and higher commodity prices could therefore have a negative impact on the economy. The Japanese yen has fluctuated widely at times and any increase in its value may cause a decline in exports that could weaken the Japanese economy. Japan has, in the past, intervened in the currency markets to attempt to maintain or reduce the value of the yen. Japanese intervention in the currency markets could cause the value of the yen to fluctuate sharply and unpredictably and could cause losses to investors. Japan has an aging workforce and has experienced a significant population decline in recent years. Japan's labor market appears to be undergoing fundamental structural changes, as a labor market traditionally accustomed to lifetime employment adjusts to meet the need for increased labor mobility, which may adversely affect Japan's economic competitiveness. Natural disasters, such as earthquakes, volcanoes, typhoons or tsunamis, could occur in Japan or surrounding areas and could negatively affect the Japanese economy and, in turn, the Portfolio.

United Kingdom: The United Kingdom has one of the largest economies in Europe, and the United States and other European countries are substantial trading partners of the United Kingdom. As a result, the British economy may be impacted by changes to the economic condition of the United States and other European countries. The British economy, along with certain other EU economies, experienced a significant economic slowdown during the recent financial crisis, and certain British financial institutions suffered significant losses, were severely under-capitalized and required government intervention to survive. The British economy relies heavily on the export of financial services to the United States and other European countries and, therefore, a prolonged slowdown in the financial services sector may have a negative impact on the British economy. Continued governmental involvement or control in certain sectors may stifle competition in certain sectors or cause adverse effects on economic growth.

Currency Risk: The value of the Portfolio's assets may be affected favorably or unfavorably by currency exchange rates, currency exchange control regulations, and delays, restrictions or prohibitions on the repatriation of foreign currencies. Foreign currency exchange rates may have significant volatility, and changes in the values of foreign currencies against the U.S. dollar may result in substantial declines in the values of the Portfolio's assets denominated in foreign currencies.

Depositary Receipts Risk: Investments in depositary receipts may be less liquid and more volatile than the underlying securities in their primary trading market. If a depositary receipt is denominated in a different currency than its underlying securities, the Portfolio will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts

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may differ from the prices of securities upon which they are based. To the extent the Portfolio invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

Derivatives Risk: Derivative transactions can create investment leverage and may have significant volatility. It is possible that a derivative transaction will result in a much greater loss than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Portfolio may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Portfolio's margin, or otherwise honor its obligations. A derivatives transaction may not behave in the manner anticipated by the Adviser or may not have the effect on the Portfolio anticipated by the Adviser.

Emerging Markets Risk: Risks of investing in emerging markets include, among others, greater political and economic instability, greater volatility in currency exchange rates, less developed securities markets, possible trade barriers, currency transfer restrictions, a more limited number of potential buyers and issuers, an emerging market country's dependence on revenue from particular commodities or international aid, less governmental supervision and regulation, unavailability of currency hedging techniques, differences in auditing and financial reporting standards, less stringent investor protection and disclosure standards, less developed public health systems, and less developed legal systems. There is also the potential for unfavorable action such as expropriation, nationalization, embargo, and acts of war. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. The Portfolio may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Portfolio's obligations. These risks are generally greater for investments in frontier market countries, which typically have smaller economies or less developed capital markets than traditional emerging market countries.

Large Shareholder Risk: To the extent a large proportion of the shares of the Portfolio are held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio Shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program.

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Portfolio's holdings may also limit the ability of the Portfolio to obtain cash to meet redemptions on a timely basis. In addition, the Portfolio, due to limitations on investments in any illiquid securities and/or the difficulty in purchasing and selling such investments, may be unable to achieve its desired level of exposure to a certain market or sector.

Small-, Mid-, and Micro-Capitalization Securities Risk: The securities of small-, mid-, and micro-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of smaller companies may trade less frequently and in smaller volumes than more widely held securities. Some securities of smaller issuers may be illiquid or may be restricted as to resale, and their values may have significant volatility. The Portfolio may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Portfolio's obligations. Returns on investments in securities of small-, mid-, and micro-capitalization companies could trail the returns on investments in securities of larger companies.

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Performance

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 18.27% (Q2, 2020)
Lowest Quarterly Return: -24.67% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. After-tax returns depend on an investor's tax situation and may differ from those shown, and after-tax returns are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). Effective October 9, 2019 (the “Benchmark Index Change Date”), the Portfolio's benchmark index changed from the MSCI ACWI ex USA Index (the “Previous Benchmark Index”) to the MSCI ACWI ex USA Investable Market Index, consistent with a change in the Portfolio's principal investment strategy to track the performance of the current index. Performance of the Portfolio prior to the Benchmark Index Change Date is therefore based on the Portfolio's investment strategy to track the Previous Benchmark Index.

	One Year	Five Years	Since Inception	Inception Date
Class				9/16/2014
Return Before Taxes	8.37%	9.89%	5.36%
Return After Taxes on Distributions	7.23%	8.73%	4.32%
Return After Taxes on Distributions and Sale of Fund Shares	4.94%	7.25%	3.68%
MSCI ACWI ex USA Investable Market Index/MSCI ACWI ex USA Index¹ (reflects no deduction for fees, expenses or taxes other than withholding taxes on reinvested dividends)	8.53%	9.88%	5.40%

¹	Returns shown are reflective of the Index for periods beginning on the Benchmark Index Change Date and the Previous Benchmark Index for periods prior to the Benchmark Index Change Date.

The Portfolio will make updated performance information, including its current net asset value, available at the Portfolio's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio are Michael Feehily, Karl Schneider, and Olga Winner. They have served on the Portfolio since inception in 2014.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

Olga Winner, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. She joined the Adviser in 2007.

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Purchase and Sale of Portfolio Shares

Generally, shares of the Portfolio may be purchased only by or on behalf of other registered investment companies or private clients that compensate the Adviser or its affiliates directly.

Purchase Minimums

To establish an account	None
To add to an existing account	None

You may purchase or redeem Portfolio Shares on any day the Portfolio is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Portfolio Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Corporation
Attention: Transfer Agent
Box 5493
Mail Code: OHD0100
North Quincy, MA 02171

By Overnight:

State Street Corporation
Attention: Transfer Agent
1 Heritage Drive
North Quincy, MA 02171

By Intermediary:

Financial Intermediaries may contact State Street Dealer Services Group at 617-662-7300 or email them at broker-dealerservices@statestreet.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Small/Mid Cap Equity Index Portfolio

Investment Objective

The State Street Small/Mid Cap Equity Index Portfolio (the “Small/Mid Cap Equity Index Portfolio” or the “Portfolio”) seeks to provide investment results that, before expenses, correspond generally to the total return of an index that tracks the performance of mid-to small- capitalization exchange traded U.S. equity securities.

Fees and Expenses of the Portfolio

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Small/Mid Cap Equity Index Portfolio (“Portfolio Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. The Portfolio's shares are offered exclusively to investors that pay fees to SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the Portfolio's investment adviser, or its affiliates; the Portfolio pays no management fee to SSGA FM, as shown in the table below.

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.00%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.02%
Total Annual Fund Operating Expenses	0.02%

Example:

1 year		3 years		5 years		10 years
$2		$6		$11		$26

Portfolio Turnover:

Principal Investment Strategies

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tion of the companies included in the Index ranged from $5.74 million to 86.68 billion. As of February 28, 2022, the Index comprised 2,545 securities. As of February 28, 2022, a significant portion of the Index comprised companies in the information technology, financials, industrials and consumer discretionary sectors, although this may change from time to time.

The Portfolio generally intends to invest in all stocks comprising the Index in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Portfolio may purchase a sample of the stocks in the Index in proportions expected by SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Portfolio, to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Portfolio may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Portfolio invests at least 80% of its net assets (plus borrowings, if any) in stocks in the Index. The Portfolio will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Portfolio may purchase or sell futures contracts on the Index, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Portfolio might do so, for example, in order to increase its investment exposure pending investment of cash in the stocks comprising the Index. Alternatively, the Portfolio might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options or swap transactions relating to the Index or any securities comprising the Index, in lieu of investing directly in the stocks making up the Index. The Portfolio may, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

The Index is sponsored by FTSE Russell (the “Index Provider”), which is not affiliated with the Portfolio or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks of investing in the Portfolio

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affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Portfolio and its investments.

Industrial Sector Risk: Stock prices for the types of companies included in this sector are affected by supply and demand both for their specific product or service and for industrial sector products in general. Government regulation, world events and economic conditions, technological developments and liabilities for environmental damage and general civil liabilities will likewise affect the performance of these companies. Aerospace and defense companies, a component of the industrial sector, can be significantly affected by government spending policies because companies involved in this industry rely to a significant extent on U.S. and foreign government demand for their products and services. Thus, the financial condition of, and investor interest in, aerospace and defense companies are heavily influenced by governmental defense spending policies which are typically under pressure from efforts to control the U.S. (and other) government budgets. Transportation stocks, a component of the industrial sector, are cyclical and have occasional sharp price movements which may result from changes in the economy, fuel prices, labor agreements and insurance costs.

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erty rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

Derivatives Risk: Derivative transactions can create investment leverage and may have significant volatility. It is possible that a derivative transaction will result in a much greater loss than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Portfolio may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Portfolio's margin, or otherwise honor its obligations. A derivatives transaction may not behave in the manner anticipated by the Adviser or may not have the effect on the Portfolio anticipated by the Adviser.

Large Shareholder Risk: To the extent a large proportion of the shares of the Portfolio are held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio Shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Portfolio to conduct its investment program.

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the Portfolio is typically subject. The Portfolio bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Portfolio may invest, leading to potential conflicts of interest. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Portfolio does so.

Performance

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 30.52% (Q2, 2020)
Lowest Quarterly Return: -27.89% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class				8/11/2015
Return Before Taxes	12.50%	15.43%	13.42%
Return After Taxes on Distributions	8.11%	13.01%	11.37%
Return After Taxes on Distributions and Sale of Fund Shares	9.46%	11.43%	10.00%
Russell Small Cap Completeness Index (reflects no deduction for fees, expenses or taxes)	12.64%	15.53%	14.75%

The Portfolio will make updated performance information, including its current net asset value, available at the Portfolio's website: www.ssga.com.

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Investment Adviser

SSGA FM serves as the investment adviser to the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio are Michael Feehily, Karl Schneider and Ted Janowsky each of which has served as a portfolio manager of the Portfolio since inception in 2015.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

Ted Janowsky, CFA, is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. He joined the Adviser in 2005.

Purchase and Sale of Portfolio Shares

Generally, shares of the Portfolio may be purchased only by or on behalf of other registered investment companies or private clients that compensate the Adviser or its affiliates directly.

Purchase Minimums

To establish an account	None
To add to an existing account	None

You may purchase or redeem Portfolio Shares on any day the Portfolio is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Portfolio Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Corporation
Attention: Transfer Agent
Box 5493
Mail Code: OHD0100
North Quincy, MA 02171

By Overnight:

State Street Corporation
Attention: Transfer Agent
1 Heritage Drive
North Quincy, MA 02171

By Intermediary:

Financial Intermediaries may contact State Street Dealer Services Group at 617-662-7300 or email them at broker-dealerservices@statestreet.com with questions.

Tax Information

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Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The State Street Institutional Investment Trust's (the “Trust”) Board of Trustees (the “Board”) may change each Portfolio's investment strategies and other policies without shareholder approval, except as otherwise indicated. The Board may change each Portfolio's investment objective without shareholder approval.

State Street Aggregate Bond Index Portfolio

Principal Investment Strategies

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Index Futures Contracts and Related Options. The Portfolio may buy and sell futures contracts and options on those futures contracts. An “index futures” contract is a contract to buy or sell units of an index at an agreed price on a specified future date. Depending on the change in value of the Index between the time when the Portfolio enters into and closes out an index future or option transaction, the Portfolio realizes a gain or loss. Options and futures transactions involve risks. For example, it is possible that changes in the prices of futures contracts will not correlate precisely with changes in the value of the Index. In those cases, use of futures contracts and related options might decrease the correlation between the return of the Portfolio and the return of the Index. In addition, the Portfolio incurs transaction costs in entering into, and closing out, positions in futures contracts and related options. Portfolios that enter into contracts with counterparties run the risk that the counterparty will be unwilling or unable to make timely settlement payments or otherwise honor its obligations. This risk is typically less for exchange-traded derivatives, such as those the Portfolio may invest in.

These costs typically have the effect of reducing the correlation between the return of the Portfolio and the return of the Index. Because the market for futures contracts and options may be illiquid, the Portfolio may have to hold a contract or option when the Adviser would otherwise have closed out the position, or it may only be able to close out at a price lower than what the Adviser believes is the fair value of the contract or option, thereby potentially reducing the return of the Portfolio.

Other Derivative Transactions. The Portfolio may enter into derivatives transactions involving options and swaps. These transactions involve many of the same risks as those described above under “Index Futures Contracts and Related Options.” In addition, since many of such transactions are conducted directly with counterparties, and not on an exchange or board of trade, the Portfolio's ability to realize any investment return on such transactions may depend on the counterparty's ability or willingness to meet its obligations.

Additional Index Information. The components of the Index are reconstituted and rebalanced monthly.

State Street Equity 500 Index II Portfolio

Principal Investment Strategies

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The Portfolio generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Portfolio may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Portfolio may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in securities that the Adviser determines have economic characteristics that are comparable to the economic characteristics of securities that comprise the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. Shareholders will receive sixty (60) days' notice prior to a change in the 80% investment policy. In addition, the Portfolio may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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State Street Global All Cap Equity ex-U.S. Index Portfolio

Principal Investment Strategies

The Portfolio is an “index” fund that seeks to track, before fees and expenses, the total return performance of the MSCI ACWI ex USA Investable Market Index (the “MSCI ACWI ex USA IMI Index” or sometimes referred to in context as the “Index”) over the long term. As an “index” fund, the Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. As of February 28, 2022, a significant portion of the Index comprised companies in the financial sector, although this may change from time to time. As of February 28, 2022, a significant portion of the Index comprised companies located in Japan and the United Kingdom and a significant portion of the Index constituents are denominated in the Euro, Yen and the Pound Sterling although this may change from time to time.

In seeking to track the performance of the Index, the Portfolio employs a sampling strategy, which means that the Portfolio is not required to purchase all of the securities represented in the Index. Instead, the Portfolio may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Portfolio will be based on a number of factors, including asset size of the Portfolio. SSGA FM generally expects the Portfolio to hold fewer than the total number of securities in the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Portfolio's investment objective.

Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) providing exposure to securities comprising the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Portfolio will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. In addition, the Portfolio may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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Indonesia, Ireland, Israel, Italy, Japan, Korea, Kuwait, Malaysia, Mexico, the Netherlands, New Zealand, Norway, Peru, Philippines, Poland, Portugal, Qatar, Russia, Saudi Arabia, Singapore, South Africa, Spain, Sweden, Switzerland, Taiwan, Thailand, Turkey, United Arab Emirates and the United Kingdom. It is not possible to invest directly in the Index.

State Street Small/Mid Cap Equity Index Portfolio

Principal Investment Strategies

The Portfolio uses a passive management strategy designed to track the performance of the Russell Small Cap Completeness Index (the “Index”). The Index is a float-adjusted, market capitalization index which measures the performance of the Russell 3000^® Index companies excluding S&P 500^® constituents. The Index is constructed to provide a comprehensive and unbiased barometer of the extended broad market beyond the S&P 500 exposure. The index is completely reconstituted annually to ensure new and growing equities are included. As of February 28, 2022, the market capitalization of the companies included in the Index ranged from $5.74 million to 86.68 billion. As of February 28, 2022, the Index comprised 2,545 securities. As of February 28, 2022, a significant portion of the Index comprised companies in the information technology, financials, industrials and consumer discretionary sectors, although this may change from time to time.

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The Portfolio generally intends to invest in all stocks comprising the Index in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Portfolio may purchase a sample of the stocks in the Index in proportions expected by SSGA FM to match generally the performance of the Index as a whole. In addition, from time to time, stocks are added to or removed from the Index. The Portfolio may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal market conditions, the Portfolio invests at least 80% of its net assets (plus borrowings, if any) in stocks in the Index. The Portfolio will provide shareholders with at least sixty (60) days' notice prior to any change in this 80% investment policy. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

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Additional Index Information. The Index's components are reconstituted annually and rebalanced monthly.

Additional Information About Risks

The Portfolios are subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure. Each principal risk without a parenthetical indicating a single Portfolio's name is applicable to each Portfolio.

Call/Prepayment Risk (principal risk for the Aggregate Bond Index Portfolio). Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by a Portfolio earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by a Portfolio are prepaid. In any such case, a Portfolio may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Portfolio's income.

Consumer Discretionary Sector Risk (principal risk for the Equity 500 Index II Portfolio and Small/Mid Cap Equity Index Portfolio). The success of consumer product manufacturers and retailers is tied closely to the performance of the overall global economy, interest rates, competition and consumer confidence. Success depends heavily on disposable household income and consumer spending. Also, companies in the consumer discretionary sector may be subject to severe competition, which may have an adverse impact on their respective profitability. Changes in demographics and consumer tastes can also affect the demand for, and success of, consumer products and services in the marketplace.

Counterparty Risk. A Portfolio will be subject to credit risk with respect to the counterparties with which the Portfolio enters into derivatives contracts and other transactions such as repurchase agreements or reverse repurchase agreements. A Portfolio's ability to profit from these types of investments and transactions will depend on the willingness and ability of its counterparty to perform its obligations. If a counterparty fails to meet its contractual obligations, a Portfolio may be unable to terminate or realize any gain on the investment or transaction, resulting in a loss to the Portfolio. A Portfolio may experience significant delays in obtaining any recovery in an insolvency, bankruptcy, or other reorganization proceeding involving its counterparty (including recovery of any collateral posted by it) and may obtain only a limited recovery or may obtain no recovery in such circumstances. If a Portfolio holds collateral posted by its counterparty, it may be delayed or prevented from realizing on the collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty. Under applicable law or contractual provisions, including if a Portfolio enters into an investment or transaction with a financial institution and such financial institution (or an affiliate of the financial institution) experiences financial difficulties, then the Portfolio may in certain situations be prevented or delayed from exercising its rights to terminate the investment or transaction, or to realize on any collateral and may result in the suspension of payment and delivery obligations of the parties under such investment or transactions or in another institution being substituted for that financial institution without the consent of the Portfolio. Further, a Portfolio may be subject to “bail-in” risk under applicable law whereby, if required by the financial institution's authority, the financial institution's liabilities could be written down, eliminated or converted into equity or an alternative instrument of ownership. A bail-in of a financial institution may result in a reduction in value of some or all of its securities and, if a Portfolio holds such securities or has entered into a transaction with such a financial security when a bail-in occurs, such Portfolio may also be similarly impacted.

Credit Risk (principal risk for the Aggregate Bond Index Portfolio). Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Portfolio may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by a Portfolio may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Portfolio owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

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its rating is downgraded, the Portfolio may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

Currency Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). Investments in issuers in different countries are often denominated in currencies other than the U.S. dollar. Changes in the values of those currencies relative to the U.S. dollar may have a positive or negative effect on the values of a Portfolio's investments denominated in those currencies. The values of other currencies relative to the U.S. dollar may fluctuate in response to, among other factors, interest rate changes, intervention (or failure to intervene) by national governments, central banks, or supranational entities such as the International Monetary Fund, the imposition of currency controls, and other political or regulatory developments. Currency values can decrease significantly both in the short term and over the long term in response to these and other developments. Continuing uncertainty as to the status of the Euro and the Economic and Monetary Union of the European Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU, or any continued uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Portfolio's portfolio investments.

Debt Securities Risk (principal risk for the Aggregate Bond Index Portfolio). The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of a Portfolio's fixed income securities to decrease, an adverse impact on the liquidity of a Portfolio's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, a Portfolio's yield can be low, and a Portfolio may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by a Portfolio may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Depositary Receipts Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). American Depositary Receipts (“ADRs”) are typically trust receipts issued by a U.S. bank or trust company that evidence an indirect interest in underlying securities issued by a foreign entity. Global Depositary Receipts (“GDRs”), European Depositary Receipts (“EDRs”), and other types of depositary receipts are typically issued by non-U.S. banks or financial institutions to evidence an interest in underlying securities issued by either a U.S. or a non-U.S. entity. Investments in non-U.S. issuers through ADRs, GDRs, EDRs, and other types of depositary receipts generally involve risks applicable to other types of investments in non-U.S. issuers. Investments in depositary receipts may be less liquid and more volatile than the underlying securities in their primary trading market. If a depositary receipt is denominated in a different currency than its underlying securities, a Portfolio will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. There may be less publicly available information regarding the issuer of the securities underlying a depositary receipt than if those securities were traded directly in U.S. securities markets. Depositary receipts may or may not be sponsored by the issuers of the underlying securities, and information regarding issuers of securities underlying unsponsored depositary receipts may be more limited than for sponsored depositary receipts. The values of depositary receipts may decline for a number of reasons relating to the issuers or sponsors of the depositary receipts, including, but not limited to, insolvency of the issuer or sponsor. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based. To the extent the Portfolio invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

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the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Adviser anticipated or a different or less favorable effect than the Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that a Portfolio may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that a Portfolio will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to a Portfolio due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

Emerging Markets Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). Investments in emerging markets are generally subject to a greater risk of loss than investments in developed markets. This may be due to, among other things, the possibility of greater market volatility, lower trading volume and liquidity, greater risk of expropriation, nationalization, and social, political and economic instability, greater reliance on a few industries, international trade or revenue from particular commodities, less developed accounting, legal and regulatory systems, higher levels of inflation, deflation or currency devaluation, greater risk of market shut down, and more significant governmental limitations on investment policy as compared to those typically found in a developed market. The Public Company Accounting Oversight Board, which regulates auditors of U.S. public companies, is unable to inspect audit work papers in certain foreign countries. Investors in foreign countries often have limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the U.S. Securities and Exchange Commission, the U.S. Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited. In addition, issuers (including governments) in emerging market countries may have less financial stability than in other countries. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. A Portfolio may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Portfolio's obligations. There is also the potential for unfavorable action such as embargo and acts of war. As a result, there will tend to be an increased risk of price volatility in investments in emerging market countries, which may be magnified by currency fluctuations relative to the U.S. dollar. Settlement and asset custody practices for transactions in emerging markets may differ from those in developed markets. Such differences may include possible delays in settlement and certain settlement practices, such as delivery of securities prior to receipt of payment, which increase the likelihood of a “failed settlement.” Failed settlements can result in losses. For these and other reasons, investments in emerging markets are often considered speculative.

Equity Investing Risk (principal risk for the Equity 500 Index II Portfolio, Global All Cap Equity ex-U.S. Index Portfolio and Small/Mid Cap Equity Index Portfolio). The market prices of equity securities owned by a Portfolio may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer, such as management performance, financial leverage, non-compliance with regulatory requirements, and reduced demand for the issuer's goods or services. The values of equity securities also may decline due to general industry or market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, or adverse investor sentiment generally. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

Extension Risk (principal risk for the Aggregate Bond Index Portfolio). During periods of rising interest rates, the average life of certain types of securities may be extended because of slower-than-expected principal payments. This may increase the period of time during which an investment earns a below-market interest rate, increase the security's duration and reduce the value of the security. Extension risk may be heightened during periods of adverse economic conditions generally, as payment rates decline due to higher unemployment levels and other factors.

Financial Sector Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio and Small/Mid Cap Equity Index Portfolio). Financial services companies are subject to extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, the interest rates and fees they can charge, the scope of their activities, the prices they can charge and the amount of capital they must maintain. Profitability is largely

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dependent on the availability and cost of capital funds and can fluctuate significantly when interest rates change or due to increased competition. In addition, deterioration of the credit markets generally may cause an adverse impact in a broad range of markets, including U.S. and international credit and interbank money markets generally, thereby affecting a wide range of financial institutions and markets. Certain events in the financial sector may cause an unusually high degree of volatility in the financial markets, both domestic and foreign, and cause certain financial services companies to incur large losses. Securities of financial services companies may experience a dramatic decline in value when such companies experience substantial declines in the valuations of their assets, take action to raise capital (such as the issuance of debt or equity securities), or cease operations. Credit losses resulting from financial difficulties of borrowers and financial losses associated with investment activities can negatively impact the sector. Insurance companies may be subject to severe price competition. Adverse economic, business or political developments could adversely affect financial institutions engaged in mortgage finance or other lending or investing activities directly or indirectly connected to the value of real estate.

Geographic Focus Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). The performance of a fund that is less diversified across countries or geographic regions will be closely tied to market, currency, economic, political, environmental, or regulatory conditions and developments in the countries or regions in which the fund invests, and may be more volatile than the performance of a more geographically-diversified fund.

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large government deficits. These issues may cause a slowdown of the Japanese economy. The Japanese yen has fluctuated widely at times and any increase in its value may cause a decline in exports that could weaken the Japanese economy. Japan has, in the past, intervened in the currency markets to attempt to maintain or reduce the value of the yen. Japanese intervention in the currency markets could cause the value of the yen to fluctuate sharply and unpredictably and could cause losses to investors. Japan has an aging workforce and has experienced a significant population decline in recent years. Japan's labor market appears to be undergoing fundamental structural changes, as a labor market traditionally accustomed to lifetime employment adjusts to meet the need for increased labor mobility, which may adversely affect Japan's economic competitiveness.

Health Care Sector Risk (principal risk for the Equity 500 Index II Portfolio). Companies in the health care sector are subject to extensive government regulation and their profitability can be significantly affected by restrictions on government reimbursement for medical expenses, rising costs of medical products and services, pricing pressure (including price discounting), limited product lines and an increased emphasis on the delivery of healthcare through outpatient services. Companies in the health care sector are heavily dependent on obtaining and defending patents, which may be time consuming and costly, and the expiration of patents may also adversely affect the profitability of these companies. Health care companies are also subject to extensive litigation based on product liability and similar claims. In addition, their products can become obsolete due to industry innovation, changes in technologies or other market developments. Many new products in the health care sector require significant research and development and may be subject to regulatory approvals, all of which may be time consuming and costly with no guarantee that any product will come to market.

Income Risk (principal risk for the Aggregate Bond Index Portfolio). A Portfolio's income may decline due to falling interest rates or other factors. Issuers of securities held by a Portfolio may call or redeem the securities during periods of falling interest rates, and the Portfolio would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Portfolio is prepaid, the Portfolio may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Portfolio may limit the Portfolio's ability to achieve its objective.

Indexing Strategy/Index Tracking Risk. Each Portfolio is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities. Each Portfolio will seek to replicate Index returns, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. Each Portfolio generally will buy and will not sell a security included in the Index as long as the security is part of the Index regardless of any sudden or material decline in value or foreseeable material decline in value of the security, even though the Adviser may make a different investment decision for other actively managed accounts or portfolios that hold the security. As a result, a Portfolio's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index (in absolute terms and by comparison with other indices) and, consequently, the performance, volatility, and risk of a Portfolio. Errors in index data, index computations or the construction of the Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on a Portfolio and its shareholders. While the Adviser seeks to track the performance of the Index (i.e.,

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achieve a high degree of correlation with the Index), a Portfolio's return may not match the return of the Index for a number of reasons. For example, the return on the sample of securities purchased by a Portfolio (or the return on securities not included in the Index) to replicate the performance of the Index may not correlate precisely with the return of the Index. Each Portfolio incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, a Portfolio may not be fully invested at times, either as a result of cash flows into or out of the Portfolio or reserves of cash held by the Portfolio to meet redemptions. The Adviser may attempt to track the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between a Portfolio's return and that of the Index. Changes in the composition of the Index and regulatory requirements also may impact a Portfolio's ability to match the return of the Index. The Adviser may apply one or more “screens” or investment techniques to refine or limit the number or types of issuers included in the Index in which a Portfolio may invest. Application of such screens or techniques may result in investment performance below that of the Index and may not produce results expected by the Adviser. Index tracking risk may be heightened during times of increased market volatility or other unusual market conditions.

Industrial Sector Risk. Industrial companies are affected by supply and demand both for their specific product or service and for industrial sector products in general. Government regulation, world events, exchange rates and economic conditions, technological developments and liabilities for environmental damage and general civil liabilities will likewise affect the performance of these companies. Aerospace and defense companies, a component of the industrial sector, can be significantly affected by government spending policies because companies involved in this industry rely, to a significant extent, on U.S. and foreign government demand for their products and services. Thus, the financial condition of, and investor interest in, aerospace and defense companies are heavily influenced by governmental defense spending policies which are typically under pressure from efforts to control the U.S. (and other) government budgets. Transportation securities, a component of the industrial sector, are cyclical and have occasional sharp price movements which may result from changes in the economy, fuel prices, labor agreements and insurance costs.

Inflation Risk (principal risk for the Aggregate Bond Index Portfolio). Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the values of a Portfolio's assets can decline. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that domestic or global economic policies will change), and the Portfolio's investments may not keep pace with inflation, which may result in losses to Portfolio investors or adversely affect the real value of shareholders' investments in the Portfolio.

Interest Rate Risk (principal risk for the Aggregate Bond Index Portfolio). Interest rate risk is the risk that the securities held by a Portfolio will decline in value because of increases in market interest rates. Duration is a measure used to determine the sensitivity of a security's price to changes in interest rates. Debt securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than debt securities with shorter durations. For example, the value of a security with a duration of five years would be expected to decrease by 5% for every 1% increase in interest rates. Falling interest rates also create the potential for a decline in a Portfolio's income and yield. Interest-only and principal-only securities are especially sensitive to interest rate changes, which can affect not only their prices but can also change the income flows and repayment assumptions about those investments. Variable and floating rate securities also generally increase or decrease in value in response to changes in interest rates, although generally to a lesser degree than fixed-rate securities. A substantial increase in interest rates may also have an adverse impact on the liquidity of a security, especially those with longer durations. Changes in governmental policy, including changes in central bank monetary policy, could cause interest rates to rise rapidly, or cause investors to expect a rapid rise in interest rates. This could lead to heightened levels of interest rate, volatility and liquidity risks for the fixed income markets generally and could have a substantial and immediate effect on the values of a Portfolio's investments.

Large-Capitalization Securities Risk (principal risk for the Equity 500 Index II Portfolio and Global All Cap Equity ex-U.S. Portfolio). Securities issued by large-capitalization companies may present risks not present in smaller companies. For example, larger companies may be unable to respond as quickly as smaller and mid-sized companies to competitive challenges or to changes in business, product, financial, or other market conditions. Larger companies may not be able to maintain growth at the high rates that may be achieved by well-managed smaller and mid-sized companies, especially during strong economic periods. Returns on investments in securities of large companies could trail the returns on investments in securities of smaller and mid-sized companies.

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Large Shareholder Risk. To the extent a large proportion of the shares of a Portfolio are highly concentrated or held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, a Portfolio is subject to the risk that these shareholders will purchase or redeem Portfolio Shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of a Portfolio to conduct its investment program. For example, they could require a Portfolio to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to shareholders, or a Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case a Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. A Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Leveraging Risk. Borrowing transactions, reverse repurchase agreements, certain derivatives transactions, securities lending transactions and other investment transactions such as when-issued, delayed-delivery, or forward commitment transactions may create investment leverage. If a Portfolio engages in transactions that have a leveraging effect on the Portfolio's investment portfolio, the value of the Portfolio will be potentially more volatile and all other risks will tend to be compounded. This is because leverage generally creates investment risk with respect to a larger base of assets than a Portfolio would otherwise have and so magnifies the effect of any increase or decrease in the value of the Portfolio's underlying assets. The use of leverage is considered to be a speculative investment practice and may result in losses to a Portfolio. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The use of leverage may cause a Portfolio to liquidate positions when it may not be advantageous to do so to satisfy repayment, interest payment, or margin obligations or to meet asset segregation or coverage requirements.

LIBOR Risk. A Fund's payment obligations, financing terms and investments in certain instruments (including debt securities and derivatives) may rely in some fashion upon the London-Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration (the administrator of LIBOR), that banks offer to charge one another for the use of short-term money. In 2017, the U.K. Financial Conduct Authority announced its intention to cease compelling banks to provide the quotations needed to sustain LIBOR after 2021. IBA ceased publication of most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of a majority of U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. Actions by regulators have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Various financial industry groups have been planning for the transition away from LIBOR and markets are developing in response to these new rates, but questions around the liquidity of the new rates and how to appropriately adjust these rates to eliminate any economic value transfer at the time of transition remain a significant concern. The transition away from and eventual elimination of LIBOR may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include “fall back” provisions addressing the transition from LIBOR. Uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by a Portfolio or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to a Portfolio.

Liquidity Risk. Liquidity risk is the risk that a Portfolio may not be able to dispose of investments or close out derivatives transactions readily at a favorable time or prices (or at all) or at prices approximating those at which a Portfolio currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Portfolio to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Portfolio may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Portfolio. In some cases, due to unanticipated levels of illiquidity a Portfolio may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

The term “illiquid investments” for this purpose means securities that a Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the securities. If any Portfolio determines at any time that it owns illiquid investments in excess

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of 15% of its net assets, it will cease to undertake new commitments to acquire illiquid securities until its holdings are no longer in excess of 15% of its NAV, report the occurrence in compliance with Rule 30b1-10 under the 1940 Act and, depending on circumstances, may take additional steps to reduce its holdings of illiquid securities.

Market Disruption and Geopolitical Risk. A Portfolio is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of a Portfolio's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Portfolio's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Portfolio. To the extent a Portfolio has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Portfolio.

Market Risk. Market prices of investments held by a Portfolio will go up or down, sometimes rapidly or unpredictably. A Portfolio's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile, and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in actual or perceived creditworthiness of issuers and general market liquidity. Even if general economic conditions do not change, the value of an investment in a Portfolio could decline if the particular industries, sectors or companies in which the Portfolio invests do not perform well or are adversely affected by events. Further, legal, political, regulatory and tax changes also may cause fluctuations in markets and securities prices. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on a Portfolio and its investments.

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Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject a Portfolio to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and a Portfolio's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Mortgage-Related and Other Asset-Backed Securities Risk (principal risk for the Aggregate Bond Index Portfolio). Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically structured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Portfolio having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Portfolio invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

In a “forward roll” transaction, a Portfolio will sell a mortgage-related security to a bank or other permitted entity and simultaneously agree to purchase a similar security from the institution at a later date at an agreed upon price. The mortgage securities that are purchased will bear the same interest rate as those sold, but generally will be collateralized by different pools of mortgages with different prepayment histories than those sold. The values of such transactions will be affected by many of the same factors that affect the values of mortgage-related securities generally. In addition, forward roll transactions may have the effect of creating investment leverage in a Portfolio.

Non-U.S. Securities Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Because non-U.S. securities are typically denominated and traded in

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currencies other than the U.S. dollar, the value of the Portfolio's assets, to the extent they are non-U.S. dollar denominated, may be affected favorably or unfavorably by currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Portfolio's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Portfolio's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Portfolio invests could cause the Portfolio's investments in that country to experience gains or losses.

Reinvestment Risk (principal risk for the Aggregate Bond Index Portfolio). Income from a Portfolio may decline when the Portfolio invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Portfolio to reinvest the proceeds in lower-yielding securities. A decline in income received by a Portfolio from its investments is likely to have a negative effect on the yield and total return of the Portfolio Shares.

Risk of Investment in Other Pools. If a Portfolio invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Portfolio is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Portfolio to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Portfolio; as a result, the Portfolio may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Portfolio bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Portfolio may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Portfolio in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Portfolio's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Portfolio directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Portfolio in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Portfolio does so.

Settlement Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). Markets in different countries have different clearance and settlement procedures and in certain markets there have been times when settlements have been unable to keep pace with the volume of transactions. Delays in settlement may increase credit risk to a Portfolio, limit the ability of a Portfolio to reinvest the proceeds of a sale of securities, hinder the ability of a Portfolio to lend its portfolio securities, and potentially subject a Portfolio to penalties for its failure to deliver to on-purchasers of securities whose delivery to a Portfolio was delayed. Delays in the settlement of securities purchased by a Portfolio may limit the ability of a Portfolio to sell those securities at times and prices it considers desirable, and may subject a Portfolio to losses and costs due to its own inability to settle with subsequent purchasers of the securities from it. A Portfolio may be required to borrow monies it had otherwise expected to receive in connection with the settlement of securities sold by it, in order to meet its obligations to others. Limits on the ability of a Portfolio to purchase or sell securities due to settlement delays could increase any variance between a Portfolio's performance and that of its benchmark index.

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Small-, Mid- and Micro-Capitalization Securities Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio and Small/Mid Cap Equity Index Portfolio). The securities of small-, mid- and micro-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of smaller companies may trade less frequently and in smaller volumes than more widely held securities. The prices of these securities may fluctuate more sharply than those of other securities, and a Portfolio may experience some difficulty in establishing or closing out positions in these securities at prevailing market prices. There may be less publicly available information about the issuers of these securities or less market interest in these securities than in the case of larger companies, both of which can cause significant price volatility. Some securities of smaller issuers may be illiquid or may be restricted as to resale. A Portfolio may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet a Portfolio's obligations. Returns on investments in securities of small-, mid- and micro-capitalization companies could trail the returns on investments in securities of larger companies.

Special Risk Considerations of Investing in China (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio). Investing in securities of Chinese issuers, including by investing in A Shares, involves certain risks and considerations not typically associated with investing in securities of U.S. issuers, including, among others, (i) more frequent (and potentially widespread) trading suspensions and U.S. or foreign government interventions or restrictions with respect to Chinese issuers, which could preclude the Fund from making certain investments or result in the Fund selling investments at disadvantageous times and which may also cause reduced liquidity and increased price volatility in such investments, (ii) the nature and extent of intervention by the Chinese government in the Chinese securities markets, whether such intervention will continue and the impact of such intervention or its discontinuation, (iii) the risk of nationalization or expropriation of assets, (iv) the risk that the Chinese government may decide not to continue to support economic reform programs, (v) limitations on the use of brokers, (vi) potentially higher rates of inflation, (vii) the unavailability of consistently-reliable economic data, (viii) the relatively small size and absence of operating history of many Chinese companies, (ix) accounting, auditing and financial reporting standards in China are different from U.S. standards and, therefore, disclosure of certain material information may not be available, (x) greater political, economic, social, legal and tax-related uncertainty, (xi) higher market volatility caused by any potential regional territorial conflicts or natural disasters, (xii) higher dependence on exports and international trade, (xiii) the risk of increased trade tariffs, sanctions, embargoes and other trade limitations, (xiv) restrictions on foreign ownership, and (xv) custody risks associated with investing through programs to access Chinese securities. Significant portions of the Chinese securities markets may become rapidly illiquid, as Chinese issuers have the ability to suspend the trading of their equity securities, and have shown a willingness to exercise that option in response to market volatility and other events. The liquidity of Chinese securities may shrink or disappear suddenly and without warning as a result of adverse economic, market or political events, or adverse investor perceptions, whether or not accurate.

Information Technology Sector Risk (principal risk for the Equity 500 Index II Portfolio and Small/Mid Cap Equity Index Portfolio). Market or economic factors impacting information technology companies could have a major effect on the value of the Portfolio's investments. The value of stocks of information technology companies is particularly vulnerable to rapid changes in technology product cycles, rapid product obsolescence, government regulation and competition, both domestically and internationally, including competition from foreign competitors with lower production costs. Like other technology companies, information technology companies may have limited product lines, markets, financial resources or personnel. Stocks of technology companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Information technology companies are heavily dependent on patent and intellectual property rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

Unconstrained Sector Risk. A Portfolio may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. When a Portfolio focuses its investments in a particular industry or sector, financial, economic, business, and other developments affecting issuers in that industry, market, or economic sector will have a greater effect on the Portfolio than if it had not focused its assets in that industry, market, or economic sector, which may increase the volatility of the Portfolio. Any such investment focus may also limit the liquidity of the

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Portfolio. In addition, investors may buy or sell substantial amounts of the Portfolio's shares in response to factors affecting or expected to affect an industry, market, or economic sector in which the Portfolio focuses its investments, resulting in extreme inflows or outflows of cash into and out of the Portfolio. Such extreme cash inflows and outflows might affect the management of the Portfolio adversely.

U.S. Government Securities Risk (principal risk for the Aggregate Bond Index Portfolio). U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor supported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of a Portfolio's investments.

Valuation Risk (principal risk for the Global All Cap Equity ex-U.S. Index Portfolio, Small/Mid Cap Equity Index Portfolio and Aggregate Bond Index Portfolio). Some portfolio holdings, potentially a large portion of a Portfolio's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. Technological issues or other service disruption issues involving third-party service providers may cause a Portfolio to value its investments incorrectly. In addition, there is no assurance that a Portfolio could sell or close out a portfolio position for the value established for it at any time, and it is possible that a Portfolio would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by a Portfolio at that time. Investors who purchase or redeem Portfolio Shares on days when the Portfolio is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Portfolio had not fair-valued the holding(s) or had used a different valuation methodology.

When-Issued, TBA and Delayed Delivery Securities Risk (principal risk for the Aggregate Bond Index Portfolio). A Portfolio may purchase securities on a when-issued, TBA or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. The prices of the securities so purchased or sold are subject to market fluctuations. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of a Portfolio's net asset value. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose a Portfolio to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

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Additional Information About Non-Principal Investment Strategies and Risks

Conflicts of Interest Risk. An investment in a Portfolio will be subject to a number of actual or potential conflicts of interest. For example, the Adviser or its affiliates may provide services to a Portfolio, such as securities lending agency services, custodial, administrative, bookkeeping, and accounting services, transfer agency and shareholder servicing, securities brokerage services, and other services for which the Portfolio would compensate the Adviser and/or such affiliates. The Portfolios may invest in other pooled investment vehicles sponsored, managed, or otherwise affiliated with the Adviser. There is no assurance that the rates at which a Portfolio pays fees or expenses to the Adviser or its affiliates, or the terms on which it enters into transactions with the Adviser or its affiliates will be the most favorable available in the market generally or as favorable as the rates the Adviser or its affiliates make available to other clients. Because of its financial interest, the Adviser will have an incentive to enter into transactions or arrangements on behalf of a Portfolio with itself or its affiliates in circumstances where it might not have done so in the absence of that interest, provided that the Adviser will comply with applicable regulatory requirements.

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Portfolios. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for a Portfolio and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by a Portfolio. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Portfolios) or otherwise using such information for the benefit of its clients or itself.

The foregoing does not purport to be a comprehensive list or complete explanation of all potential conflicts of interests which may affect a Portfolio. A Portfolio may encounter circumstances, or enter into transactions, in which conflicts of interest that are not listed or discussed above may arise.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Portfolios) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Portfolio or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Portfolio's ability to calculate its NAV, cause the release of private shareholder information or confidential Portfolio information, impede trading, cause reputational damage, and subject a Portfolio to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Portfolio assets and transactions, shareholder ownership of Portfolio Shares, and other data integral to the functioning of a Portfolio inaccessible or inaccurate or incomplete. A Portfolio may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Portfolio and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Portfolio relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Portfolio from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Portfolios. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Portfolio invests, which could result in material adverse consequences for such issuers, and may cause a Portfolio's investment in such securities to lose value.

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Index Construction Risk. A security included in an Index may not exhibit the characteristic or provide the specific exposure for which it was selected and consequently a Portfolio's holdings may not exhibit returns consistent with that characteristic or exposure.

Index Licensing Risk. It is possible that the license under which the Adviser or a Portfolio is permitted to replicate or otherwise use an Index will be terminated or may be disputed, impaired or cease to remain in effect. In such a case, the Adviser may be required to replace the Index with another index which it considers to be appropriate in light of the investment strategy of a Portfolio. The use of any such substitute index may have an adverse impact on a Portfolio's performance. In the event that the Adviser is unable to identify a suitable replacement for the Index, it may determine to terminate a Portfolio.

Portfolio Turnover Risk (risk for the Aggregate Bond Index Portfolio). A Portfolio may engage in frequent trading of its portfolio securities. Portfolio turnover generally involves a number of direct and indirect costs and expenses to a Portfolio, including, for example, brokerage commissions, dealer mark-ups and bid/asked spreads, and transaction costs on the sale of securities and reinvestment in other securities. The costs related to increased portfolio turnover have the effect of reducing a Portfolio's investment return, and the sale of securities by a Portfolio may result in the realization of taxable capital gains, including short-term capital gains, which are taxed to individuals as ordinary income.

Securities Lending Risk. Each Portfolio may lend portfolio securities in an amount not to exceed 40% of the value of its net assets. For these purposes, net assets shall exclude the value of all assets received as collateral for the loan. Such loans may be terminated at any time. Any such loans must be continuously secured by collateral (either cash or other obligations as may be permitted under the Portfolios' securities lending program) maintained on a current basis in an amount at least equal to the market value of the securities loaned by a Portfolio, marked to market each trading day. In a loan transaction, as compensation for lending its securities, a Portfolio will receive a portion of the dividends or interest accrued on the securities held as collateral or, in the case of cash collateral, a portion of the income from the investment of such cash. In addition, a Portfolio will receive the amount of all dividends, interest and other distributions on the loaned securities. However, the borrower has the right to vote the loaned securities. A Portfolio will call loans to vote proxies if a material issue affecting the investment is to be voted upon. Efforts to recall such securities promptly may be unsuccessful, especially for foreign securities or thinly traded securities, and may involve expenses to a Portfolio. Securities lending involves the risk that the Portfolio may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. Should the borrower of the securities fail financially, a Portfolio may experience delays in recovering the securities or exercising its rights in the collateral. Loans are made only to borrowers that are deemed by the securities lending agent to be of good financial standing. In a loan transaction, a Portfolio will also bear the risk of any decline in value of securities acquired with cash collateral. Each Portfolio expects to invest cash collateral in a pooled investment vehicle advised by the Adviser. With respect to index funds, to the extent the collateral

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provided or investments made with cash collateral differ from securities included in the relevant Index, such collateral or investments may have a greater risk of loss than the securities included in the Index. In addition, a Portfolio will be subject to the risk that any income generated by reinvesting cash collateral is lower than any fees the Portfolio has agreed to pay a borrower.

Portfolio Holdings Disclosure

The Portfolios' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Each Portfolio is a separate, diversified series of the State Street Institutional Investment Trust (the “Trust”), which is an open-end management investment company organized as a business trust under the laws of the Commonwealth of Massachusetts.

Investment Adviser

SSGA FM serves as the investment adviser to each Portfolio and, subject to the oversight of the Board, is responsible for the investment management of each Portfolio. The Adviser provides an investment management program for each Portfolio and manages the investment of each Portfolio's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the U.S. Securities and Exchange Commission (“SEC”) under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

The Portfolios' shares are offered exclusively to other investors (including without limitation, registered investment companies, private investment pools, bank collective funds, and investment separate accounts) that pay fees to SSGA FM or its affiliates. The Portfolios pay no investment advisory fees to SSGA FM. The fees paid by those investment vehicles to SSGA FM (or its affiliates) vary depending on a number of factors, including by way of example, the services provided, the risks borne by SSGA FM (or its affiliates), fee rates paid by competitive investment vehicles, and in some cases direct negotiation with investors.

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to each of the Small/Mid Cap Equity Index Portfolio and the Global All Cap Equity ex-U.S. Index Portfolio, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Portfolio, and/or (ii) to reimburse the Portfolio for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees and distribution, shareholder servicing and sub-transfer agency fees) exceed average daily net assets on an annual basis of 0.08% for the Global All Cap Equity ex-U.S. Index Portfolio and 0.03% for the Small/Mid Cap Equity Index Portfolio. These waiver and/or reimbursement arrangements may not be terminated prior to April 30, 2023 except with approval of the Portfolios' Board of Trustees.

SSGA FM, as the investment adviser to the Equity 500 Index II Portfolio and the Aggregate Bond Index Portfolio, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Portfolio and/or (ii) to reimburse the Portfolio to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses and distribution, shareholder servicing, and sub-transfer agency fees) exceed average daily net assets on an annual basis of 0.02% for the Equity 500 Index II Portfolio and 0.025% for Aggregate Bond Index Portfolio. These waiver and/or reimbursement arrangements may not be terminated prior to April 30, 2023 except with approval of the Portfolios' Board of Trustees.

A discussion regarding the Board's consideration of the Portfolio's Investment Advisory Agreement for each of the Aggregate Bond Index Portfolio, the Equity 500 Index II Portfolio, the Global All Cap Equity ex-U.S. Index Portfolio and the Small/Mid Cap Equity Index Portfolio is provided in the Trust's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

Portfolio Management

The Adviser manages the Portfolios using a team of investment professionals. The team approach is used to create an environment that encourages the flow of investment ideas. The portfolio managers within the team work together in a cohesive manner to develop and enhance techniques that drive the investment process for the respective investment strategy. This approach requires portfolio managers to share a variety of responsibilities, including investment strategy and analysis, while retaining responsibility for the implementation of the strategy within any particular portfolio. The approach also enables the team to draw upon the resources of other groups within SSGA. Each portfolio management team is overseen by the SSGA Investment Committee.

The table below identifies the professionals primarily responsible for the day-to-day management of each Portfolio:

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Portfolio Managers		Portfolios
Michael Feehily, Karl Schneider and Amy Scofield		Equity 500 Index II Portfolio
Marc DiCosimo and Joanna Madden		Aggregate Bond Index Portfolio
Michael Feehily, Olga Winner and Karl Schneider		Global All Cap Equity ex-U.S. Index Portfolio
Michael Feehily, Ted Janowsky and Karl Schneider		Small/Mid Cap Equity Index Portfolio

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Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Portfolios is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator, Custodian, Transfer Agent and Dividend Disbursing Agent

The Adviser serves as administrator of each Portfolio. State Street, a subsidiary of State Street Corporation, serves as sub-administrator, custodian, transfer agent and dividend disbursing agent (the “Transfer Agent”) for each Portfolio. Each Portfolio pays an annual fee that is accrued daily and payable monthly for the administration, sub-administration, custody and transfer agency services SSGA FM and State Street provide.

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Portfolios' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

The Trustees of the Trust oversee generally the operations of the Portfolios and the Trust. The Trust enters into contractual arrangements with various parties, including, among others, the Portfolios' investment adviser, custodian, transfer agent, and accountants, who provide services to the Portfolios. Shareholders are not parties to any such contractual arrangements or intended beneficiaries of those contractual arrangements, and those contractual arrangements are not intended to create in any shareholder any right to enforce them directly against the service providers or to seek any remedy under them directly against the service providers.

This Prospectus provides information concerning the Trust and the Portfolios that you should consider in determining whether to purchase shares of the Portfolios. Neither this Prospectus, nor the related SAI, is intended, or should be read, to be or to give rise to an agreement or contract between the Trust or the Portfolios and any investor, or to give rise to any rights in any shareholder or other person other than any rights under federal or state law that may not be waived.

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Shareholder Information

Determination of Net Asset Value

Each Portfolio determines its NAV per share once each business day as of the scheduled close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in a Portfolio. The NAV of each class of a Portfolio's Shares is calculated by dividing the value of the assets of the Portfolio attributable to that class less the liabilities of the Portfolio attributable to that class by the number of shares in the class outstanding. As noted in this Prospectus, each Portfolio may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when each Portfolio does not price its shares. Consequently, the NAV of each Portfolio's shares may change on days when shareholders are not able to purchase or redeem the Portfolio's shares. Purchase and redemption orders for Portfolio Shares are processed, respectively, at the NAV next determined after the Portfolio accepts a purchase order or receives a redemption request in good form. Each Portfolio values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolios' Board, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by a Portfolio occurs after the close of a related exchange but before the determination of a Portfolio's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Portfolio would have received had it sold the investment. To the extent that a Portfolio invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published NAVs per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Purchasing Shares

Generally, shares of a Portfolio may be purchased only by or on behalf of other registered investment companies or private clients for which the Adviser or an affiliate serves as investment adviser (or in a similar capacity). The price for Portfolio Shares is the NAV per share. Orders received in good form (a purchase order is in good form if it meets the requirements implemented from time to time by a Portfolio or its Transfer Agent, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) will be priced at the NAV next calculated after the order is accepted by the Portfolios.

There is no minimal initial investment in a Portfolio and there is no minimum subsequent investment. (If you purchase shares by check, your order will not be in good form until the Portfolio's transfer agent receives federal funds for the check.) The Portfolios reserve the right to cease accepting investments at any time or to reject any purchase order.

In accordance with certain federal regulations, the Trust is required to obtain, verify and record information that identifies each entity that applies to open an account. For this reason, when you open (or change ownership of) an account, the Trust will request certain information, including your name, residential/business address, date of birth (for individuals) and taxpayer identification number or other government identification number and other information that will allow us to identify you which will be used to verify your identity. The Trust may also request to review other identification documents such as driver license, passport or documents showing the existence of the business entity. If you do not provide sufficient information to verify your identity, the Trust will not open an account for you. As required by law, the Trust may employ various procedures, such as comparing your information to fraud databases or requesting additional information and documentation from you, to ensure that the information supplied by you is correct. The Trust reserves the right to reject any purchase order for any reason, including failure to provide the Trust with information necessary to confirm your identity as required by law.

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If you are purchasing through a Financial Intermediary, please contact your intermediary as their requirements may differ.

Redeeming Shares

An investor may redeem all or any portion of its investment at the NAV next determined after it submits a redemption request, in proper form, to a Portfolio. A Portfolio will typically pay the proceeds of the redemption on the next business day after the redemption, but in any event no more than seven days after the redemption. A Portfolio may delay paying redemption proceeds if the request is made within 15 days of the purchase of such Portfolio Shares and the payment or customer verification process is not complete. There will be no such delay for redemptions following purchases paid by federal funds wire or by bank cashier's check, certified check or treasurer's check. The right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed beyond seven days during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or, to the extent otherwise permitted by the 1940 Act, as amended, if an emergency exists as a result of which disposal by a Portfolio of securities owned by it is not reasonably practicable or it is not reasonably practicable for a Portfolio fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of investors of the Portfolios.

Under normal circumstances, each Portfolio expects to meet redemption requests by using cash or cash equivalents in its portfolio and/or selling portfolio assets to generate cash. The Portfolios also may pay redemption proceeds using cash obtained through borrowing arrangements (including under the Portfolios' line of credit, which is shared across all registered funds advised by SSGA FM (other than money market funds)) that may be available from time to time.

A Portfolio may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Portfolio reasonably believes that a cash redemption may have a substantial impact on the Portfolio and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

During periods of deteriorating or stressed market conditions, when an increased portion of a Portfolio's portfolio may be comprised of less liquid investments, or during extraordinary or emergency circumstances, a Portfolio may be more likely to pay redemption proceeds with cash obtained through short-term borrowing arrangements (if available) or by giving you securities.

If your account is held through an Intermediary, please contact them for additional assistance and advice on how to redeem your shares.

About Mail Transactions

If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location and a Portfolio's net asset value may change over those days. You might consider using express rather than regular mail if you believe time of receipt of your transaction request to be sensitive.

Policies to Prevent Market Timing

Frequent purchases and redemptions of Portfolio Shares may present risks for other shareholders of the Portfolios, which may include, among other things, interference in the efficient management of a Portfolio's portfolio, dilution in the value of Portfolio Shares held by long-term shareholders, increased brokerage and administrative costs and forcing the Portfolios to hold excess levels of cash.

Therefore, the Trust's Board of Trustees has adopted policies and procedures designed to detect and prevent inappropriate short-term trading activity that is harmful to the Portfolios. Because most of the interests in the Portfolios are held by investors indirectly through one or more financial intermediaries, the Portfolios do not generally have information about the identity of those investors or about transactions effected by those investors. Rather, the Portfolios and their service providers periodically review cash inflows and outflows from and to those intermediaries in an attempt to detect inappropriate trading activity by investors holding shares through those intermediaries. The Portfolios may seek to obtain

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underlying account trading activity information from financial intermediaries when, in the Adviser's judgment, the trading activity suggests possible market timing. There is no assurance that the Portfolios or the Adviser will be able to determine whether trading by an investor holding shares through a financial intermediary is engaged in trading activity that may be harmful to the Portfolios or their shareholders.

The Portfolios reserve the right in their discretion to reject any purchase, in whole or in part including, without limitation, by a person whose trading activity in Portfolio Shares the Adviser believes could be harmful to the Portfolios. The Portfolios may decide to restrict purchase activity in their shares based on various factors, including, without limitation, whether frequent purchase and sale activity will disrupt portfolio management strategies and adversely affect performance. There can be no assurance that the Portfolios, the Adviser or State Street will identify all frequent purchase and sale activity affecting the Portfolios.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a Portfolio identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to a Portfolio (if you hold shares directly with a Portfolio) or to your financial intermediary (if you do not hold shares directly with a Portfolio).

Dividends, Distributions and Tax Considerations

Dividends of investment income and capital gain distributions of the Portfolios will be declared and paid at least annually. Any investment income and capital gains that have not been distributed by December of each calendar year are generally distributed at such time. When a Portfolio distributes investment income or capital gains, the NAV per share is reduced by the amount of the distribution. Dividends of investment income and capital gain distributions will be paid in additional shares on the record date unless you have elected to receive them in cash.

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Portfolios' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (800) 647-7327, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Tax Considerations

The following discussion is a summary of some important U.S. federal income tax considerations generally applicable to an investment in a Portfolio. Your investment in a Portfolio may have other tax implications. Please consult your tax advisor about federal, state, local, foreign or other tax laws applicable to you. Investors, including non-U.S. investors, may wish to consult the SAI tax section for additional disclosure.

Each Portfolio has elected to be treated as a regulated investment company and intends each year to qualify and to be eligible to be treated as such. A regulated investment company generally is not subject to tax at the corporate level on income and gains that are timely distributed to shareholders. In order to qualify and be eligible for treatment as a regulated investment company, a Portfolio must, among other things, satisfy diversification, 90% gross income and distribution requirements. A Portfolio's failure to qualify as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders.

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For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long a Portfolio owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Portfolio Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that a Portfolio owned (or is deemed to have owned) for more than one year that are properly reported by a Portfolio as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that a Portfolio owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income. Distributions of investment income properly reported by a Portfolio as derived from “qualified dividend income,” which will not include income from the Portfolio's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by both the shareholder and the Portfolio. Distributions are taxable to you even if they are paid from income or gains earned by a Portfolio before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of a Portfolio's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Portfolio's shares, and, in general, as capital gain thereafter.

Any gain resulting from the redemption or other taxable disposition of Portfolio Shares generally will also be taxable to you as either short-term or long-term capital gain, depending upon how long you held such Portfolio Shares.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Portfolio, including any capital gain dividends, and net gains recognized on the redemption of Portfolio Shares.

A Portfolio's income from or proceeds of dispositions of its investments in non-U.S. assets may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. In certain instances, a Portfolio may be entitled to elect to pass through to its shareholders a credit (or deduction, for a shareholder that itemizes deductions and so chooses) for foreign taxes (if any) borne with respect to foreign securities income earned by the Portfolio. If the Portfolio so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the Portfolio. There can be no assurance that a Portfolio will make such election, even if it is eligible to do so. If a Portfolio does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Portfolio; in that case the foreign tax will nonetheless reduce the Portfolio's taxable income. Shareholders that are not subject to U.S. federal income tax, and those who invest in a Portfolio through tax-advantaged accounts (including those who invest through IRAs or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit or deduction passed through by the Portfolio. Under certain circumstances, if a Portfolio receives a refund of foreign taxes paid in respect of a prior year, the value of Portfolio Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Portfolio's foreign taxes for the current year could be reduced.

Certain of a Portfolio's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of a Portfolio's distributions, and may require the Portfolio to sell its investments at a time when it is not advantageous to do so.

If you are not a U.S. person, dividends paid by a Portfolio that the Portfolio properly reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends, each as further defined in the SAI, are not subject to withholding of U.S. federal income tax, provided that certain requirements are met. A Portfolio is permitted, but is not required, to report any part of its dividends as are eligible for such treatment. A Portfolio's dividends other than those the Portfolio so reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends generally will be subject to U.S. withholding tax at a 30% rate (or lower applicable treaty rate). See each Portfolio's SAI for further information.

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The U.S. Treasury and IRS generally require a Portfolio to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Internal Revenue Code of 1986, as amended, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the Internal Revenue Service (the “IRS”) for redemptions of Portfolio Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Portfolios and not through a Financial Intermediary, The Transfer Agent will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

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Financial Highlights

The financial highlight tables are intended to help you understand each Portfolio's financial performance since each Portfolio's inception. Certain information reflects the performance results for a single Portfolio Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in each Portfolio (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with each Portfolio's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of each Portfolio's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET AGGREGATE BOND INDEX PORTFOLIO

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period


	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$107.23	$102.60	$97.10	$100.00	$99.10
Income (loss) from investment operations:
Net investment income (loss) (b)	1.61	0.65	2.80	2.60	2.30
Net realized and unrealized gain (loss)	(3.46)	7.25	5.70	(2.80)	1.00
Total from investment operations	(1.85)	7.90	8.50	(0.20)	3.30
Contribution from Affiliate (Note 5)	—	0.00(c)	—	—	—
Distributions to shareholders from:
Net investment income	(1.96)	(2.67)	(3.00)	(2.70)	(2.40)
Net realized gains	—	(0.60)	—	—	—
Total distributions	(1.96)	(3.27)	(3.00)	(2.70)	(2.40)
Net asset value, end of period	$103.42	$107.23	$102.60	$97.10	$100.00
Total return (d)	(1.72)%	7.86%(e)	8.69%	(0.12)%	3.38%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,099,436	$1,415,008	$1,033,578	$846,759	$687,541
Ratios to average net assets:
Total expenses	0.02%	0.03%	0.04%	0.04%	0.06%
Net expenses	0.01%	0.03%	0.03%	0.03%	0.03%
Net investment income (loss)	1.55%	2.20%	2.76%	2.73%	2.31%
Portfolio turnover rate	21%(f)	37%(f)	69%	90%	99%

(a)	After the close of trading on April 17, 2020, the State Street Aggregate Bond Index Portfolio underwent a 1-for-10 reverse sharesplit. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Amount is less than $0.005 per share.
(d)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(e)	If an Affiliate had not made a contribution during the year ended December 31, 2020, the total return would have remained 7.86%.
(f)	Portfolio turnover rate excludes to-be-announced (“TBA”) transactions.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET EQUITY 500 INDEX II PORTFOLIO

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period


	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$344.77	$302.40	$235.40	$261.40	$226.20
Income (loss) from investment operations:
Net investment income (loss) (b)	5.30	5.44	5.60	5.20	5.00
Net realized and unrealized gain (loss)	92.75	49.45	68.40	(17.20)	44.20
Total from investment operations	98.05	54.89	74.00	(12.00)	49.20
Distributions to shareholders from:
Net investment income	(5.07)	(5.28)	(5.20)	(5.20)	(5.40)
Net realized gains	(5.66)	(7.24)	(1.80)	(8.80)	(8.60)
Total distributions	(10.73)	(12.52)	(7.00)	(14.00)	(14.00)
Net asset value, end of period	$432.09	$344.77	$302.40	$235.40	$261.40
Total return (c)	28.52%	18.30%	31.41%	(4.42)%	21.66%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$7,078,644	$4,732,247	$3,223,997	$2,634,533	$2,199,181
Ratios to average net assets:
Total expenses	0.02%	0.02%	0.03%	0.03%	0.03%
Net expenses	0.02%	0.02%	0.02%	0.02%	0.03%
Net investment income (loss)	1.34%	1.79%	2.01%	1.93%	1.98%
Portfolio turnover rate	6%	6%	21%	8%	30%

(a)	On April 17, 2020, the State Street Equity 500 Index II Portfolio underwent a 1-for-20 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 11.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET GLOBAL ALL CAP EQUITY EX- U.S. INDEX PORTFOLIO

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period


	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$116.43	$106.60	$90.20	$108.10	$87.30
Income (loss) from investment operations:
Net investment income (loss) (b)	3.09	2.28	3.20	3.00	2.60
Net realized and unrealized gain (loss)	6.56	9.49	16.40	(18.20)	21.20
Total from investment operations	9.65	11.77	19.60	(15.20)	23.80
Other capital	—	(0.00)(c)	—	—	—
Distributions to shareholders from:
Net investment income	(3.17)	(1.94)	(3.20)	(2.70)	(2.50)
Net realized gains	—	—	—	(0.00)(c)	(0.50)
Total distributions	(3.17)	(1.94)	(3.20)	(2.70)	(3.00)
Net asset value, end of period	$122.91	$116.43	$106.60	$90.20	$108.10
Total return (d)	8.37%	11.07%	21.70%	(13.99)%	27.20%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$4,772,699	$3,270,962	$2,097,299	$1,907,599	$1,655,261
Ratios to average net assets:
Total expenses	0.05%	0.05%	0.06%	0.06%	0.06%
Net expenses	0.05%	0.05%	0.06%	0.06%	0.06%
Net investment income (loss)	2.48%	2.29%	3.19%	2.89%	2.59%
Portfolio turnover rate	2%	2%	28%	4%	2%

(a)	After the close of trading on April 17, 2020, the State Street Global All Cap Equity Index Portfolio underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Amount is less than $0.005 per share.
(d)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET SMALL/MID CAP EQUITY INDEX PORTFOLIO

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period


	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$327.73	$254.60	$206.20	$242.00	$213.00
Income (loss) from investment operations:
Net investment income (loss) (b)	3.50	3.01	3.60	3.80	3.40
Net realized and unrealized gain (loss)	36.64	79.67	54.20	(26.20)	35.20
Total from investment operations	40.14	82.68	57.80	(22.40)	38.60
Other capital	0.00(c)	—	—	—	—
Distributions to shareholders from:
Net investment income	(3.47)	(2.90)	(3.40)	(3.80)	(3.00)
Net realized gains	(48.09)	(6.65)	(6.00)	(9.60)	(6.60)
Total distributions	(51.56)	(9.55)	(9.40)	(13.40)	(9.60)
Net asset value, end of period	$316.31	$327.73	$254.60	$206.20	$242.00
Total return (d)	12.50%	32.46%	27.98%	(9.07)%	18.20%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,616,128	$1,065,859	$749,202	$628,732	$464,870
Ratios to average net assets:
Total expenses	0.02%	0.03%	0.05%	0.05%	0.07%
Net expenses	0.02%	0.03%	0.03%	0.03%	0.03%
Net investment income (loss)	0.96%	1.19%	1.48%	1.52%	1.46%
Portfolio turnover rate	28%	52%	51%	22%	21%

(a)	After the close of trading on April 17, 2020, the State Street Small/Mid Cap Equity Index Portfolio underwent a 1-for-20 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split. See Note 12.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Amount is less than $0.005 per share.
(d)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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Index/Trademark Licenses/Disclaimers

The State Street Equity 500 Index II Portfolio is not sponsored, endorsed, sold or marketed by SPDJI, Dow Jones, S&P, any of their respective affiliates (collectively, “S&P Dow Jones Indices”). S&P Dow Jones Indices does not make any representation or warranty, express or implied, to the owners of the State Street Equity 500 Index II Portfolio or any member of the public regarding the advisability of investing in securities generally or in the State Street Equity 500 Index II Portfolio particularly or the ability of the Index to track general market performance. S&P Dow Jones Indices licenses to Licensee the Index and certain trademarks, service marks and/or trade names of S&P Dow Jones Indices and/or its licensors. The Index is determined, composed and calculated by S&P Dow Jones Indices without regard to Licensee or the State Street Equity 500 Index II Portfolio. S&P Dow Jones Indices has no obligation to take the needs of Licensee or the owners of the State Street Equity 500 Index II Portfolio into consideration in determining, composing or calculating the Index. S&P Dow Jones Indices is not responsible for and has not participated in the determination of the prices, and amount of the State Street Equity 500 Index II Portfolio or the timing of the issuance or sale of the State Street Equity 500 Index II Portfolio or in the determination or calculation of the equation by which the State Street Equity 500 Index II Portfolio is to be converted into cash, surrendered or redeemed, as the case may be. S&P Dow Jones Indices has no obligation or liability in connection with the administration, marketing or trading of the State Street Equity 500 Index II Portfolio. S&P Dow Jones Indices LLC is not an investment or tax advisor. Inclusion of a security within an index is not a recommendation by S&P Dow Jones Indices to buy, sell, or hold such security, nor is it considered to be investment advice.

NEITHER S&P DOW JONES INDICES NOR THIRD PARTY LICENSOR GUARANTEES THE ADEQUACY, ACCURACY, TIMELINESS AND/OR THE COMPLETENESS OF THE INDEX OR ANY DATA RELATED THERETO OR ANY COMMUNICATION, INCLUDING BUT NOT LIMITED TO, ORAL OR WRITTEN COMMUNICATION (INCLUDING ELECTRONIC COMMUNICATIONS) WITH RESPECT THERETO. S&P DOW JONES INDICES AND THIRD PARTY LICENSOR SHALL NOT BE SUBJECT TO ANY DAMAGES OR LIABILITY FOR ANY ERRORS, OMISSIONS, OR DELAYS THEREIN. S&P DOW JONES INDICES AND THIRD PARTY LICENSOR MAKES NO EXPRESS OR IMPLIED WARRANTIES, AND EXPRESSLY DISCLAIMS ALL WARRANTIES, OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE OR AS TO RESULTS TO BE OBTAINED BY LICENSEE, OWNERS OF THE STATE STREET EQUITY 500 INDEX II PORTFOLIO, OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE INDICES OR WITH RESPECT TO ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT WHATSOEVER SHALL S&P DOW JONES INDEX OR THIRD PARTY LICENSOR BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES INCLUDING BUT NOT LIMITED TO, LOSS OF PROFITS, TRADING LOSSES, LOST TIME OR GOODWILL, EVEN IF THEY HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, WHETHER IN CONTRACT, TORT, STRICT LIABILITY, OR OTHERWISE. THERE ARE NO THIRD PARTY BENEFICIARIES OF ANY AGREEMENTS OR ARRANGEMENTS BETWEEN S&P DOW JONES INDICES AND LICENSEE, OTHER THAN THE LICENSORS OF S&P DOW JONES INDICES.

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DOES NOT MAKE ANY WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY THE LICENSEE, OWNERS OF THE PRODUCTS OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE BLOOMBERG INDEX OR ANY DATA RELATED THERETO. BLOOMBERG DOES NOT MAKE ANY EXPRESS OR IMPLIED WARRANTIES AND EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE BLOOMBERG INDEX OR ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, TO THE MAXIMUM EXTENT ALLOWED BY LAW, BLOOMBERG, ITS LICENSORS, AND ITS AND THEIR RESPECTIVE EMPLOYEES, CONTRACTORS, AGENTS, SUPPLIERS, AND VENDORS SHALL HAVE NO LIABILITY OR RESPONSIBILITY WHATSOEVER FOR ANY INJURY OR DAMAGES—WHETHER DIRECT, INDIRECT, CONSEQUENTIAL, INCIDENTAL, PUNITIVE OR OTHERWISE—ARISING IN CONNECTION WITH THE PRODUCTS OR BLOOMBERG INDEX OR ANY DATA OR VALUES RELATING THERETO—WHETHER ARISING FROM THEIR NEGLIGENCE OR OTHERWISE, EVEN IF NOTIFIED OF THE POSSIBILITY THEREOF.

THE STATE STREET GLOBAL ALL CAP EQUITY EX-U.S. INDEX PORTFOLIO IS NOT SPONSORED, ENDORSED, SOLD OR PROMOTED BY MSCI INC. (“MSCI”), MSCI'S PARENT COMPANY, ANY OF MSCI'S OR MSCI'S PARENT COMPANY'S DIRECTLY OR INDIRECTLY HELD SUBSIDIARIES, ANY OF MSCI'S OR MSCI'S PARENT COMPANY'S INFORMATION PROVIDERS OR ANY THIRD PARTY INVOLVED IN, OR RELATED TO, COMPILING, COMPUTING OR CREATING ANY MSCI INDEX (COLLECTIVELY, THE “MSCI PARTIES”).THE MSCI INDICES ARE THE EXCLUSIVE PROPERTY OF MSCI. MSCI AND THE MSCI INDEX NAMES ARE SERVICE MARK(S) OF MSCI OR ITS AFFILIATES AND HAVE BEEN LICENSED FOR USE FOR CERTAIN PURPOSES BY THE LICENSEE. NONE OF THE MSCI PARTIES MAKES ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY REGARDING THE ADVISABILITY OF INVESTING IN FUNDS GENERALLY OR IN THE MSCI FUNDS PARTICULARLY OR THE ABILITY OF ANY MSCI INDEX TO TRACK CORRESPONDING STOCK MARKET PERFORMANCE. MSCI OR ITS AFFILIATES ARE THE LICENSORS OF CERTAIN TRADEMARKS, SERVICE MARKS AND TRADE NAMES AND OF THE MSCI INDICES WHICH ARE DETERMINED, COMPOSED AND CALCULATED BY MSCI WITHOUT REGARD TO THE MSCI FUNDS OR THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY. NONE OF THE MSCI PARTIES HAS ANY OBLIGATION TO TAKE THE NEEDS OF THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY INTO CONSIDERATION IN DETERMINING, COMPOSING OR CALCULATING THE MSCI INDICES. NONE OF THE MSCI PARTIES IS RESPONSIBLE FOR OR HAS PARTICIPATED IN THE DETERMINATION OF THE TIMING OF, PRICES AT, OR QUANTITIES OF THE MSCI FUNDS TO BE ISSUED OR IN THE DETERMINATION OR CALCULATION OF THE EQUATION BY OR THE CONSIDERATION INTO WHICH THE MSCI FUNDS ARE REDEEMABLE. FURTHER, NONE OF THE MSCI PARTIES HAS ANY OBLIGATION OR LIABILITY TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY IN CONNECTION WITH THE ADMINISTRATION, MARKETING OR OFFERING OF THE MSCI FUNDS.

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The State Street Small/Mid Cap Equity Index Portfolio has been developed solely by the Adviser. The State Street Small/Mid Cap Equity Index Portfolio is not in any way connected to or sponsored, endorsed, sold or promoted by the London Stock Exchange Group plc and its group undertakings (collectively, the “LSE Group”). FTSE Russell is a trading name of certain of the LSE Group companies.

The Index is calculated by or on behalf of FTSE International Limited or its affiliate, agent or partner. The LSE Group does not accept any liability whatsoever to any person arising out of (a) the use of, reliance on or any error in the Index or (b) investment in or operation of the State Street Small/Mid Cap Equity Index Portfolio. The LSE Group makes no claim, prediction, warranty or representation either as to the results to be obtained from the State Street Small/Mid Cap Equity Index Portfolio or the suitability of the Index for the purpose to which it is being put by the Adviser.

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For more information about the Portfolios:

The Portfolios' SAI includes additional information about the Portfolios and is incorporated by reference into this document. Additional information about the Portfolios' investments is available in the Portfolios' most recent annual and semi-annual reports to shareholders. In a Portfolio's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year. The Portfolios' SAI is available, without charge, upon request. The Portfolios' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Portfolios may make inquiries to the Portfolios to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Portfolio's annual and semi-annual reports to shareholders are available, free of charge, on the Portfolios' website at www.ssga.com.

Reports and other information about the Portfolios are available free of charge on the EDGAR Database on the SEC's Internet site at http://www.sec.gov. Copies of this information also may be obtained, after paying a duplicating fee, by electronic request at the following E-mail address: publicinfo@sec.gov.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITCFSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Target Retirement 2020 Fund
Class I (SSBNX) Class K (SSBOX) Class R3 (SSADX)

State Street Target Retirement 2025 Fund
Class I (SSBRX) Class K (SSBSX) Class R3 (SSAHX)

State Street Target Retirement 2030 Fund
Class I (SSBWX) Class K (SSBYX) Class R3 (SSAJX)

State Street Target Retirement 2035 Fund
Class I (SSCJX) Class K (SSCKX) Class R3 (SSAZX)

State Street Target Retirement 2040 Fund
Class I (SSCNX) Class K (SSCQX) Class R3 (SSAKX)

State Street Target Retirement 2045 Fund
Class I (SSDDX) Class K (SSDEX) Class R3 (SSAOX)

State Street Target Retirement 2050 Fund
Class I (SSDJX) Class K (SSDLX) Class R3 (SSAUX)

State Street Target Retirement 2055 Fund
Class I (SSDOX) Class K (SSDQX) Class R3 (SSAWX)

State Street Target Retirement 2060 Fund
Class I (SSDWX) Class K (SSDYX) Class R3 (SSAYX)

State Street Target Retirement 2065 Fund
Class I (SSFJX) Class K (SSFKX) Class R3 (SSFPX)

State Street Target Retirement Fund
Class I (SSFNX) Class K (SSFOX) Class R3 (SSFQX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Class I, Class K and Class R3 Shares of the applicable Funds.

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Fund Summaries	1
State Street Target Retirement 2020 Fund	1
State Street Target Retirement 2025 Fund	12
State Street Target Retirement 2030 Fund	23
State Street Target Retirement 2035 Fund	34
State Street Target Retirement 2040 Fund	45
State Street Target Retirement 2045 Fund	56
State Street Target Retirement 2050 Fund	67
State Street Target Retirement 2055 Fund	78
State Street Target Retirement 2060 Fund	89
State Street Target Retirement 2065 Fund	100
State Street Target Retirement Fund	111
Additional Information About Investment Objectives, Principal Strategies and Risks	121
Additional Information About Non-Principal Investment Strategies and Risks	135
Portfolio Holdings Disclosure	137
Management and Organization	138
Shareholder Information	140
Dividends, Distributions and Tax Considerations	149
Financial Intermediary Arrangements	151
Financial Highlights	153
Appendix A – Underlying Funds	176
Index/Trademark Licenses/Disclaimers	181

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State Street Target Retirement 2020 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2020 Fund (the “Target Retirement 2020 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.28%	0.08%	0.33%
Acquired Fund Fees and Expenses	0.11%	0.11%	0.11%
Total Annual Fund Operating Expenses	0.44%	0.24%	0.74%
Less Fee Waivers and/or Expense Reimbursements³	(0.15%)	(0.15%)	(0.15%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$126	$231	$540
Class K	$9	$62	$120	$291
Class R3	$60	$221	$397	$904

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2020 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2020 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

The Underlying Funds employ a wide array of investment styles. For example, the Underlying Funds can buy and sell common stocks of companies of any size, corporate bonds of varying credit quality, U.S. government and agency bonds, mortgage- and asset-backed securities, commodities, real estate and money market instruments. They may hold U.S. or non-U.S. investments. The Underlying Funds may use derivative instruments of any kind, including futures contracts, forward currency contracts, credit default swaps, interest rate swaps and commodities-related derivatives. Derivatives may be used by an Underlying Fund for hedging or risk management purposes, as a substitute for direct investment, or otherwise to seek to enhance the Underlying Fund's total return.

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The glide path depicted in the chart below shows how the Fund's strategic target allocations among asset classes are expected generally to place more emphasis on fixed income investments and less on equity investments as the target retirement date approaches.

The glide path shows the Fund's long term strategic target allocations. The Fund's actual allocations may differ. The Adviser periodically reviews the Fund's target asset allocations and may, at any time, in its discretion, change the target asset allocations or deviate from the target asset allocations when it believes doing so is appropriate to pursue the Fund's investment objective. The glide path is presented only as an illustration of how the process of re-allocation occurs as the Fund approaches its target date.

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.:

Underlying Funds		Target Retirement 2020 Fund
State Street Equity 500 Index II Portfolio		19.13%
State Street Small/Mid Cap Equity Index Portfolio		3.87%
State Street Global All Cap Equity ex-U.S. Index Portfolio		14.50%
State Street Aggregate Bond Index Portfolio		21.34%
SPDR Bloomberg 1-10 Year TIPS ETF		18.00%
SPDR Bloomberg High Yield Bond ETF		7.00%
SPDR Dow Jones Global Real Estate ETF		5.00%
SPDR Portfolio Long Term Treasury ETF		0.00%
SPDR Portfolio Intermediate Term Treasury ETF		0.00%
SPDR Portfolio Short Term Treasury ETF		8.93%
SPDR Portfolio Short Term Corporate Bond ETF		2.23%

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The Fund's actual allocations are expected to differ over time. The Adviser periodically reviews the Fund's target allocations to underlying investment options and may, at any time, in its discretion, change the target allocations or deviate from the target allocations when it believes doing so is appropriate to pursue the Fund's investment objective. The Adviser may modify the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. The table is presented for illustrative purposes only. More current information regarding the Fund's allocations may be available on its website: www.ssga.com.

Principal Risks

The Fund is subject to the following principal risks. You could lose money by investing in the Fund. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund may not achieve its investment objective. An investment in the Fund is not guaranteed, and you may experience losses, including losses near, at, or after the target date. There is no guarantee that the Fund will provide adequate portfolio growth or income at and through your retirement. The Fund is not intended to be a complete investment program, but rather is intended for investment as part of a diversified investment portfolio. Investors should consult their own advisers as to the role of the Fund in their overall investment programs. Except as otherwise stated, references in this section to “the Fund” or “a Fund” may relate to the Fund, one or more Underlying Funds, or both. The risks described below may arise out of the Fund's direct investments or the Fund's investments in one or more of the Underlying Funds. All or a portion of the Underlying Funds are managed pursuant to a passive investment strategy, while the Fund is managed pursuant to an active investment strategy. You will find additional information about each Underlying Fund's risks in its prospectus and SAI.

Asset Allocation Risk: The Fund's investment performance depends upon the successful allocation by the Adviser of the Fund's assets among asset classes, geographical regions, industry sectors, and specific issuers and investments. There is no guarantee that the Adviser's allocation techniques and decisions will produce the desired results.

Risk of Investment in Other Pools: When the Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected and is exposed indirectly to all of the risks applicable to an investment in such other pool. The investment policies of the other pool may not be the same as those of the Fund; as a result, an investment in the other pool may be subject to additional or different risks than those to which the Fund is typically subject. The Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so.

Target Date Assumptions Risk: This is the risk that assumptions and forecasts used by the Adviser in developing the Fund's asset allocation glide path are not in line with actual future investment returns and participant savings activities, which could result in losses near, at, or after the target date year or could result in the Fund not providing adequate income at and through retirement.

Longevity Risk: This is the risk that you will outlive your retirement assets.

Below Investment-Grade Securities Risk: Lower-quality debt securities (“high yield” or “junk” bonds) are considered predominantly speculative, and can involve a substantially greater risk of default than higher quality debt securities. Issuers of lower-quality debt securities may have substantially greater risk of insolvency or bankruptcy than issuers of higher-quality debt securities. They can be illiquid, and their values can have significant volatility and may decline significantly over short periods of time. Lower-quality debt securities tend to be more sensitive to adverse news about the issuer, or the market or economy in general.

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Commodities Risk: Commodity prices can have significant volatility, and exposure to commodities can cause the net asset value (“NAV”) of Fund Shares to decline or fluctuate in a rapid and unpredictable manner. A liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them.

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embargo, and acts of war. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. These risks are generally greater for investments in frontier market countries, which typically have smaller economies or less developed capital markets than traditional emerging market countries.

Inflation Risk: Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the values of a fund's assets can decline. Inflation rates may change frequently and drastically as a result of various factors and the Fund's investments may not keep pace with inflation, which may result in losses to Fund investors or adversely affect the real value of shareholders' investments in the Fund.

Inflation-Indexed Securities Risk: The principal amount of an inflation-indexed security typically increases with inflation and decreases with deflation, as measured by a specified index. It is possible that, in a period of declining inflation rates, the Fund could receive at maturity less than the initial principal amount of an inflation-indexed security. Changes in the values of inflation-indexed securities may be difficult to predict, and it is possible that an investment in such securities will have an effect different from that anticipated by the Adviser.

IPO Risk: The Fund may at times have the opportunity to invest in securities offered in initial public offerings (“IPOs”). IPOs involve companies that have no public operating history and therefore entail more risk than established public companies. The prices of securities offered in IPOs can have significant volatility and the Fund may lose money on an investment in such securities. IPO investments in which other clients of the Adviser invest may not be made available to the Fund.

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Large Shareholder Risk: To the extent a large proportion of the shares of the Fund are held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Fund is subject to the risk that these shareholders will purchase or redeem Fund Shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Fund to conduct its investment program.

Management Risk: The Fund is actively managed. The Adviser's judgments about the attractiveness, relative value, or potential appreciation of a particular sector, security, commodity or investment strategy may prove to be incorrect, and may cause the Fund to incur losses. There can be no assurance that the Adviser's investment techniques and decisions will produce the desired results.

Modeling Risk: The Adviser uses quantitative models in an effort to enhance returns and manage risk. Any imperfections, errors or limitations in these models could limit any benefit to the Fund from the use of the models, or could result in incorrect outputs or in investment outcomes different from or opposite to those expected or desired by the Adviser. There can be no assurance that the models will behave as expected in all market conditions. In addition, computer programming used to create quantitative models, or the data on which such models operate, might contain one or more errors.

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kets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent that the Fund buys securities denominated in a foreign currency, there are special risks such as changes in currency exchange rates and the risk that a foreign government could regulate foreign exchange transactions. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

Real Estate Sector Risk: An investment in a real property company may be subject to risks similar to those associated with direct ownership of real estate, including, by way of example, the possibility of declines in the value of real estate, losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, environmental liability, zoning laws, regulatory limitations on rents, property taxes, and operating expenses. Some real property companies have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property.

REIT Risk: Real estate investment trusts (“REITs”) are subject to the risks associated with investing in the securities of real property companies. In particular, REITs may be affected by changes in the values of the underlying properties that they own or operate. Further, REITs are dependent upon specialized management skills, and their investments may be concentrated in relatively few properties, or in a small geographic area or a single property type. REITs are also subject to heavy cash flow dependency and, as a result, are particularly reliant on the proper functioning of capital markets. A variety of economic and other factors may adversely affect a lessee's ability to meet its obligations to a REIT. In the event of a default by a lessee, the REIT may experience delays in enforcing its rights as a lessor and may incur substantial costs associated in protecting its investments. In addition, a REIT could fail to qualify for favorable regulatory treatment.

Small-, Mid- and Micro-Capitalization Securities Risk: The securities of small-, mid- and micro-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of smaller companies may trade less frequently and in smaller volumes than more widely held securities. Some securities of smaller issuers may be illiquid or may be restricted as to resale, and their values may have significant volatility. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. Returns on investments in securities of small-, mid- and micro-capitalization companies could trail the returns on investments in securities of larger companies.

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When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 11.23% (Q2, 2020)
Lowest Quarterly Return: -10.89% (Q1, 2020)

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Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	8.79%	9.16%	7.29%
Return After Taxes on Distributions	6.84%	7.61%	6.02%
Return After Taxes on Distributions and Sale of Fund Shares	6.10%	6.80%	5.39%
Class K Return Before Taxes	9.55%	9.34%	7.42%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2020 Composite Index (reflects no deduction for fees, expenses or taxes)	9.65%	9.38%	7.56%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

The professionals primarily responsible for the day-to-day management of the Fund are Seamus Quinn and Michael Narkiewicz. Mr. Quinn has served as a portfolio manager of the Fund since 2022 and Mr. Narkiewicz has served as a portfolio manager of the Fund since 2018.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

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Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2025 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2025 Fund (the “Target Retirement 2025 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.28%	0.08%	0.33%
Acquired Fund Fees and Expenses	0.09%	0.09%	0.09%
Total Annual Fund Operating Expenses	0.42%	0.22%	0.72%
Less Fee Waivers and/or Expense Reimbursements³	(0.13%)	(0.13%)	(0.13%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$122	$222	$517
Class K	$9	$58	$111	$267
Class R3	$60	$217	$388	$882

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2025 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2025 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2025 Fund
State Street Equity 500 Index II Portfolio		25.09%
State Street Small/Mid Cap Equity Index Portfolio		5.75%
State Street Global All Cap Equity ex-U.S. Index Portfolio		20.66%
State Street Aggregate Bond Index Portfolio		20.16%
SPDR Bloomberg 1-10 Year TIPS ETF		13.01%
SPDR Bloomberg High Yield Bond ETF		6.58%
SPDR Dow Jones Global Real Estate ETF		3.50%
SPDR Portfolio Long Term Treasury ETF		2.10%
SPDR Portfolio Intermediate Term Treasury ETF		0.90%
SPDR Portfolio Short Term Treasury ETF		1.79%
SPDR Portfolio Short Term Corporate Bond ETF		0.45%

Table of Contents

Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 13.51% (Q2, 2020)
Lowest Quarterly Return: -12.49% (Q1, 2020)

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Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	10.03%	10.91%	8.56%
Return After Taxes on Distributions	8.21%	9.27%	7.20%
Return After Taxes on Distributions and Sale of Fund Shares	6.84%	8.14%	6.37%
Class K Return Before Taxes	10.81%	11.10%	8.70%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2025 Composite Index (reflects no deduction for fees, expenses or taxes)	11.01%	11.17%	8.87%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2030 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2030 Fund (the “Target Retirement 2030 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.28%	0.08%	0.33%
Acquired Fund Fees and Expenses	0.06%	0.06%	0.06%
Total Annual Fund Operating Expenses	0.39%	0.19%	0.69%
Less Fee Waivers and/or Expense Reimbursements³	(0.10%)	(0.10%)	(0.10%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$115	$209	$483
Class K	$9	$51	$97	$233
Class R3	$60	$211	$374	$849

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2030 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2030 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2030 Fund
State Street Equity 500 Index II Portfolio		30.20%
State Street Small/Mid Cap Equity Index Portfolio		7.87%
State Street Global All Cap Equity ex-U.S. Index Portfolio		27.43%
State Street Aggregate Bond Index Portfolio		16.16%
SPDR Bloomberg 1-10 Year TIPS ETF		3.92%
SPDR Bloomberg High Yield Bond ETF		5.41%
SPDR Dow Jones Global Real Estate ETF		1.00%
SPDR Portfolio Long Term Treasury ETF		5.60%
SPDR Portfolio Intermediate Term Treasury ETF		2.40%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

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Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 15.28% (Q2, 2020)
Lowest Quarterly Return: -13.54% (Q1, 2020)

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Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	10.76%	12.03%	9.36%
Return After Taxes on Distributions	9.08%	10.57%	8.17%
Return After Taxes on Distributions and Sale of Fund Shares	7.32%	9.24%	7.19%
Class K Return Before Taxes	11.37%	12.17%	9.47%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2030 Composite Index (reflects no deduction for fees, expenses or taxes)	11.56%	12.25%	9.62%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2035 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2035 Fund (the “Target Retirement 2035 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.28%	0.08%	0.33%
Acquired Fund Fees and Expenses	0.05%	0.05%	0.05%
Total Annual Fund Operating Expenses	0.38%	0.18%	0.68%
Less Fee Waivers and/or Expense Reimbursements³	(0.09%)	(0.09%)	(0.09%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$113	$204	$472
Class K	$9	$49	$92	$221
Class R3	$60	$208	$370	$838

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2035 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2035 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2035 Fund
State Street Equity 500 Index II Portfolio		32.80%
State Street Small/Mid Cap Equity Index Portfolio		9.75%
State Street Global All Cap Equity ex-U.S. Index Portfolio		31.45%
State Street Aggregate Bond Index Portfolio		12.82%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		3.18%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

Table of Contents

Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 16.53% (Q2, 2020)
Lowest Quarterly Return: -15.07% (Q1, 2020)

Table of Contents

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	11.38%	12.60%	9.79%
Return After Taxes on Distributions	9.92%	11.25%	8.69%
Return After Taxes on Distributions and Sale of Fund Shares	7.61%	9.75%	7.59%
Class K Return Before Taxes	12.18%	12.82%	9.96%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2035 Composite Index (reflects no deduction for fees, expenses or taxes)	12.39%	12.90%	10.07%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2040 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2040 Fund (the “Target Retirement 2040 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.28%	0.08%	0.33%
Acquired Fund Fees and Expenses	0.04%	0.04%	0.04%
Total Annual Fund Operating Expenses	0.37%	0.17%	0.67%
Less Fee Waivers and/or Expense Reimbursements³	(0.08%)	(0.08%)	(0.08%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

Table of Contents

	1 year	3 years	5 years	10 years
Class I	$30	$111	$200	$460
Class K	$9	$47	$88	$209
Class R3	$60	$206	$365	$827

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2040 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2040 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2040 Fund
State Street Equity 500 Index II Portfolio		34.72%
State Street Small/Mid Cap Equity Index Portfolio		11.86%
State Street Global All Cap Equity ex-U.S. Index Portfolio		34.43%
State Street Aggregate Bond Index Portfolio		9.00%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		0.00%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

Table of Contents

Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 17.61% (Q2, 2020)
Lowest Quarterly Return: -16.52% (Q1, 2020)

Table of Contents

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	11.75%	13.03%	10.09%
Return After Taxes on Distributions	10.28%	11.70%	8.99%
Return After Taxes on Distributions and Sale of Fund Shares	7.89%	10.14%	7.85%
Class K Return Before Taxes	13.15%	13.34%	10.31%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2040 Composite Index (reflects no deduction for fees, expenses or taxes)	13.28%	13.41%	10.44%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2045 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2045 Fund (the “Target Retirement 2045 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.29%	0.09%	0.34%
Acquired Fund Fees and Expenses	0.04%	0.04%	0.04%
Total Annual Fund Operating Expenses	0.38%	0.18%	0.68%
Less Fee Waivers and/or Expense Reimbursements³	(0.09%)	(0.09%)	(0.09%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

Table of Contents

	1 year	3 years	5 years	10 years
Class I	$30	$113	$204	$472
Class K	$9	$49	$92	$221
Class R3	$60	$208	$370	$838

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2045 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2045 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2045 Fund
State Street Equity 500 Index II Portfolio		35.45%
State Street Small/Mid Cap Equity Index Portfolio		14.00%
State Street Global All Cap Equity ex-U.S. Index Portfolio		36.55%
State Street Aggregate Bond Index Portfolio		4.00%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		0.00%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

Table of Contents

Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 18.68% (Q2, 2020)
Lowest Quarterly Return: -17.92% (Q1, 2020)

Table of Contents

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	13.08%	13.59%	10.49%
Return After Taxes on Distributions	11.76%	12.33%	9.40%
Return After Taxes on Distributions and Sale of Fund Shares	8.57%	10.61%	8.17%
Class K Return Before Taxes	13.83%	13.76%	10.61%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2045 Composite Index (reflects no deduction for fees, expenses or taxes)	14.12%	13.86%	10.77%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2050 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2050 Fund (the “Target Retirement 2050 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.30%	0.10%	0.35%
Acquired Fund Fees and Expenses	0.04%	0.04%	0.04%
Total Annual Fund Operating Expenses	0.39%	0.19%	0.69%
Less Fee Waivers and/or Expense Reimbursements³	(0.10%)	(0.10%)	(0.10%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

Table of Contents

	1 year	3 years	5 years	10 years
Class I	$30	$115	$209	$483
Class K	$9	$51	$97	$233
Class R3	$60	$211	$374	$849

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2050 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2050 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2050 Fund
State Street Equity 500 Index II Portfolio		35.80%
State Street Small/Mid Cap Equity Index Portfolio		15.95%
State Street Global All Cap Equity ex-U.S. Index Portfolio		38.25%
State Street Aggregate Bond Index Portfolio		0.00%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		0.00%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

Table of Contents

Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 19.08% (Q2, 2020)
Lowest Quarterly Return: -18.49% (Q1, 2020)

Table of Contents

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	13.12%	13.66%	10.51%
Return After Taxes on Distributions	11.81%	12.37%	9.39%
Return After Taxes on Distributions and Sale of Fund Shares	8.60%	10.66%	8.18%
Class K Return Before Taxes	14.37%	13.96%	10.70%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2050 Composite Index (reflects no deduction for fees, expenses or taxes)	14.57%	14.05%	10.90%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2055 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2055 Fund (the “Target Retirement 2055 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.33%	0.13%	0.38%
Acquired Fund Fees and Expenses	0.04%	0.04%	0.04%
Total Annual Fund Operating Expenses	0.42%	0.22%	0.72%
Less Fee Waivers and/or Expense Reimbursements³	(0.13%)	(0.13%)	(0.13%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

Table of Contents

	1 year	3 years	5 years	10 years
Class I	$30	$122	$222	$517
Class K	$9	$58	$111	$267
Class R3	$60	$217	$388	$882

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2055 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2055 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

Table of Contents

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2055 Fund
State Street Equity 500 Index II Portfolio		35.80%
State Street Small/Mid Cap Equity Index Portfolio		15.95%
State Street Global All Cap Equity ex-U.S. Index Portfolio		38.25%
State Street Aggregate Bond Index Portfolio		0.00%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		0.00%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

Table of Contents

Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

Table of Contents

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 19.05% (Q2, 2020)
Lowest Quarterly Return: -18.45% (Q1, 2020)

Table of Contents

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	13.32%	13.78%	10.58%
Return After Taxes on Distributions	12.13%	12.58%	9.53%
Return After Taxes on Distributions and Sale of Fund Shares	8.63%	10.76%	8.24%
Class K Return Before Taxes	14.31%	13.98%	10.70%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2055 Composite Index (reflects no deduction for fees, expenses or taxes)	14.57%	14.05%	10.90%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Table of Contents

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Table of Contents

State Street Target Retirement 2060 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2060 Fund (the “Target Retirement 2060 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.42%	0.22%	0.47%
Acquired Fund Fees and Expenses	0.04%	0.04%	0.04%
Total Annual Fund Operating Expenses	0.51%	0.31%	0.81%
Less Fee Waivers and/or Expense Reimbursements³	(0.22%)	(0.22%)	(0.22%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$141	$263	$619
Class K	$9	$77	$152	$372
Class R3	$60	$237	$428	$981

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2060 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2060 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

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The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2060 Fund
State Street Equity 500 Index II Portfolio		35.80%
State Street Small/Mid Cap Equity Index Portfolio		15.95%
State Street Global All Cap Equity ex-U.S. Index Portfolio		38.25%
State Street Aggregate Bond Index Portfolio		0.00%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		0.00%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

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Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

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When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 18.98% (Q2, 2020)
Lowest Quarterly Return: -18.44% (Q1, 2020)

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Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	13.75%	13.82%	10.59%
Return After Taxes on Distributions	12.61%	12.73%	9.47%
Return After Taxes on Distributions and Sale of Fund Shares	8.80%	10.78%	8.14%
Class K Return Before Taxes	14.34%	13.97%	10.68%	9/30/2014
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	18.47%	15.14%
State Street Target Retirement 2060 Composite Index (reflects no deduction for fees, expenses or taxes)	14.57%	14.05%	10.90%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

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Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Target Retirement 2065 Fund

Investment Objective

The investment objective of the State Street Target Retirement 2065 Fund (the “Target Retirement 2065 Fund” or the “Fund”) is to seek capital growth and income over the long term.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	1.40%	1.20%	1.45%
Acquired Fund Fees and Expenses	0.04%	0.04%	0.04%
Total Annual Fund Operating Expenses	1.49%	1.29%	1.79%
Less Fee Waivers and/or Expense Reimbursements³	(1.20%)	(1.20%)	(1.20%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.
²	Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.
³	The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2022 (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.09% of average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2022 except with approval of the Fund's Board of Trustees.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$353	$699	$1,676
Class K	$9	$290	$592	$1,451
Class R3	$60	$446	$857	$2,006

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. From the Fund's commencement of operations on March 30, 2020 to the most recent fiscal year end, the Fund's portfolio turnover rate was 20% of the average value of its portfolio.

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement 2065 Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund is intended for investors expecting to retire around the year 2065 and who are likely to stop making new investments in the Fund at that time. The Fund is designed for an investor who plans to withdraw the value of the investor's account gradually following that date. The Adviser seeks to optimize the Fund's “glide path” for the wealth accumulation, wealth preservation, and income generation phases of retirement planning and includes adjustments in the critical years immediately preceding and following the retirement date. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund – its glide path – to what is generally seen to be a more conservative approach to reduce (but not to eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. A fund intended for investors who have already achieved retirement age would typically invest a greater portion of its assets in bonds and cash items, with a relatively smaller allocation to equity securities.

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The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement 2065 Fund
State Street Equity 500 Index II Portfolio		35.80%
State Street Small/Mid Cap Equity Index Portfolio		15.95%
State Street Global All Cap Equity ex-U.S. Index Portfolio		38.25%
State Street Aggregate Bond Index Portfolio		0.00%
SPDR Bloomberg 1-10 Year TIPS ETF		0.00%
SPDR Bloomberg High Yield Bond ETF		0.00%
SPDR Dow Jones Global Real Estate ETF		0.00%
SPDR Portfolio Long Term Treasury ETF		7.00%
SPDR Portfolio Intermediate Term Treasury ETF		3.00%
SPDR Portfolio Short Term Treasury ETF		0.00%
SPDR Portfolio Short Term Corporate Bond ETF		0.00%

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Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

103

104

105

106

107

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. (“FINRA”) rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 6.71% (Q2, 2021)
Lowest Quarterly Return: -1.46% (Q3, 2021)

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Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Since Inception	Inception Date
Class I Return Before Taxes	14.09%	32.38%	3/30/2020
Return After Taxes on Distributions	13.21%	30.56%
Return After Taxes on Distributions and Sale of Fund Shares	8.65%	24.60%
Class K Return Before Taxes	14.39%	32.67%	3/30/2020
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	28.71%	42.61%
State Street Target Retirement 2065 Composite Index (reflects no deduction for fees, expenses or taxes)	14.57%	35.38%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

109

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Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

110

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State Street Target Retirement Fund

Investment Objective

The investment objective of the State Street Target Retirement Fund (the “Target Retirement Fund” or the “Fund”) is to seek current income and, secondarily, capital growth.

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

	Class I	Class K	Class R3
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I	Class K	Class R3
Management Fee	0.05%	0.05%	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%	0.00%	0.25%
Other Expenses^1,2	0.30%	0.10%	0.35%
Acquired Fund Fees and Expenses	0.12%	0.12%	0.12%
Total Annual Fund Operating Expenses	0.47%	0.27%	0.77%
Less Fee Waivers and/or Expense Reimbursements³	(0.18%)	(0.18%)	(0.18%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.29%	0.09%	0.59%

¹	Other Expenses have been restated to reflect current fees for Class I shares.

Other Expenses for the R3 Class shares are based on estimates for the current fiscal year.

Example:

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	1 year	3 years	5 years	10 years
Class I	$30	$133	$245	$574
Class K	$9	$69	$134	$325
Class R3	$60	$228	$410	$937

Portfolio Turnover:

Principal Investment Strategies

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, manages the Target Retirement Fund using a proprietary asset allocation strategy. The Fund is a “fund of funds” that invests in a combination of mutual funds and ETFs sponsored by the Adviser or its affiliates (the “Underlying Funds”). The Underlying Funds may invest in a wide variety of asset classes, including equity and fixed-income securities of issuers anywhere in the world, including emerging markets investments, and including, among others, high yield, commodity, and real estate investments. The Underlying Funds may invest in obligations of domestic U.S. issuers, non-U.S. issuers, or both.

The Fund's assets are allocated among the Underlying Funds according to a target asset allocation strategy that emphasizes fixed income, but also includes a smaller allocation to equity and certain other asset classes. The Fund is intended for use as part of an overall investment strategy by an investor who is already in retirement.

The following table shows the Fund's strategic target allocations to the Underlying Funds as of the date of this Prospectus.

Underlying Funds		Target Retirement Fund
State Street Equity 500 Index II Portfolio		15.57%
State Street Small/Mid Cap Equity Index Portfolio		2.93%
State Street Global All Cap Equity ex-U.S. Index Portfolio		11.50%
State Street Aggregate Bond Index Portfolio		20.00%
SPDR Bloomberg 1-10 Year TIPS ETF		18.00%
SPDR Bloomberg High Yield Bond ETF		7.00%
SPDR Dow Jones Global Real Estate ETF		5.00%
SPDR Portfolio Long Term Treasury ETF		0.00%
SPDR Portfolio Intermediate Term Treasury ETF		0.00%
SPDR Portfolio Short Term Treasury ETF		16.00%
SPDR Portfolio Short Term Corporate Bond ETF		4.00%

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Principal Risks

Longevity Risk: This is the risk that you will outlive your retirement assets.

113

114

115

116

117

When-Issued, TBA and Delayed Delivery Securities Risk: The Fund may purchase securities on a when-issued, to-be-announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund's NAV. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Performance

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of a broad measure of market performance and those of a composite of accounts with similar investment objectives (the “Composite Index”). The Composite Index is a custom composite which comprises each index tracked by the Underlying Funds of the Fund. The S&P 500 Index is a well-known stock market index that includes common stocks of 500 companies from a number of sectors and that measures the performance of the large-cap sector of the market. Performance for Class R3 shares will be available after the class has been in operation for one calendar year. The bar chart shows how the Class I shares' returns have varied for each full calendar year shown. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 8.83% (Q2, 2020)
Lowest Quarterly Return: -7.78% (Q1, 2020)

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Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class I				9/30/2014
Return Before Taxes	6.87%	7.36%	5.81%
Return After Taxes on Distributions	4.97%	6.12%	4.74%
Return After Taxes on Distributions and Sale of Fund Shares	4.90%	5.37%	4.20%
Class K Return Before Taxes	7.92%	7.56%	5.94%	9/30/2014
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)	-1.54%	3.57%	3.15%
State Street Target Retirement Composite Index (reflects no deduction for fees, expenses or taxes)	7.93%	7.52%	6.06%

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Seamus Quinn, CFA, CAIA, is a Principal of the Adviser and a Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2012.

Michael Narkiewicz is a Vice President of the Adviser and a Senior Portfolio Manager in the Investment Solutions Group. He joined the Adviser in 2013.

Purchase and Sale of Fund Shares

Purchase Minimums

Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None
Class R3
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

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Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

State Street Target Retirement Funds

The Target Retirement 2020 Fund, Target Retirement 2025 Fund, Target Retirement 2030 Fund, Target Retirement 2035 Fund, Target Retirement 2040 Fund, Target Retirement 2045 Fund, Target Retirement 2050 Fund, Target Retirement 2055 Fund, Target Retirement 2060 Fund, Target Retirement 2065 and Target Retirement Fund are referred to collectively in this Prospectus as the “Target Retirement Funds” or the “Funds.”

Principal Investment Strategies

The Adviser invests each Target Retirement Fund among Underlying Funds according to a proprietary asset allocation. Each Fund's (except for the Retirement Fund) name refers to the approximate retirement year of the investors for whom the Fund's asset allocation strategy is intended. As the target date for a Fund approaches, the Adviser will adjust the asset allocation and risk profile of the Fund (except for the Retirement Fund) – its glide path – to a what is generally seen to be a more conservative approach to reduce (but not eliminate) risk by increasing the allocation to asset classes that have historically been subject to lower levels of volatility. For example, a Fund with a target retirement date far into the future will typically invest a greater portion of its assets in asset classes with higher risk profiles and the potential for higher returns. By contrast, the Retirement Fund is intended for investors in their retirement years. The Adviser allocates the Fund's assets according to a target asset allocation that emphasizes fixed income funds but also includes an allocation to equity and certain other funds.

When the target asset allocation of another Target Retirement Fund matches the Retirement Fund's target asset allocation, generally five years after the Fund's target retirement date (as shown in the glide path above), it is expected that the Fund will be combined with the Retirement Fund, and the Fund's shareholders will become shareholders of the Retirement Fund. This may be done without a vote of shareholders if the Trustees determine at the time of the proposed combination that combining the Fund with the Retirement Fund is in the best interests of the Fund, the Retirement Fund and their shareholders.

The Adviser intends to manage each Target Retirement Fund according to the Fund's target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. The Adviser may modify the target asset allocation strategy or the selection of Underlying Funds for any Target Retirement Fund from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future.

Each Target Retirement Fund will bear a pro rata share of its Underlying Funds' expenses. Each Target Retirement Fund also bears all of the risks associated with the investment strategies used by its Underlying Funds.

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The tables below set forth each Target Retirement Fund's current strategic target allocations to the Underlying Funds as of the date of this Prospectus and show how each Fund's allocations among asset classes are expected generally to become more conservative as the target retirement date approaches (i.e., more emphasis on fixed income and less on equity):

Underlying Funds	Retirement	2020	2025	2030	2035	2040
State Street Equity 500 Index II Portfolio	15.58%	20.00%	25.97%	30.65%	33.14%	34.85%
State Street Small/Mid Cap Equity Index Portfolio	2.93%	4.12%	6.06%	8.14%	10.06%	12.16%
State Street Global All Cap Equity ex-U.S. Index Portfolio	11.50%	15.25%	21.72%	28.22%	31.93%	34.74%
State Street Aggregate Bond Index Portfolio	20.00%	21.19%	19.88%	15.99%	12.18%	8.25%
SPDR Bloomberg 1-10 Year TIPS ETF	18.00%	18.00%	11.71%	2.47%	0.00%	0.00%
SPDR Bloomberg High Yield Bond ETF	7.00%	7.00%	6.45%	5.16%	2.70%	0.00%
SPDR Dow Jones Global Real Estate ETF	5.00%	5.00%	3.13%	0.63%	0.00%	0.00%
SPDR Portfolio Long Term Treasury ETF	0.00%	0.00%	2.63%	6.13%	7.00%	7.00%
SPDR Portfolio Intermediate Term Treasury ETF	0.00%	0.00%	1.13%	2.63%	3.00%	3.00%
SPDR Portfolio Short Term Treasury ETF	16.00%	7.55%	1.07%	0.00%	0.00%	0.00%
SPDR Portfolio Short Term Corporate Bond ETF	4.00%	1.89%	0.27%	0.00%	0.00%	0.00%

Underlying Funds	2045	2050	2055	2060	2065
State Street Equity 500 Index II Portfolio	35.53%	35.80%	35.80%	35.80%	35.80%
State Street Small/Mid Cap Equity Index Portfolio	14.35%	15.95%	15.95%	15.95%	15.95%
State Street Global All Cap Equity ex-U.S. Index Portfolio	36.87%	38.25%	38.25%	38.25%	38.25%
State Street Aggregate Bond Index Portfolio	3.25%	0.00%	0.00%	0.00%	0.00%
SPDR Bloomberg 1-10 Year TIPS ETF	0.00%	0.00%	0.00%	0.00%	0.00%
SPDR Bloomberg High Yield Bond ETF	0.00%	0.00%	0.00%	0.00%	0.00%
SPDR Dow Jones Global Real Estate ETF	0.00%	0.00%	0.00%	0.00%	0.00%
SPDR Portfolio Long Term Treasury ETF	7.00%	7.00%	7.00%	7.00%	7.00%
SPDR Portfolio Intermediate Term Treasury ETF	3.00%	3.00%	3.00%	3.00%	3.00%
SPDR Portfolio Short Term Treasury ETF	0.00%	0.00%	0.00%	0.00%	0.00%
SPDR Portfolio Short Term Corporate Bond ETF	0.00%	0.00%	0.00%	0.00%	0.00%

The Funds' actual allocations are expected to differ over time. The Adviser periodically reviews each Fund's target allocations to underlying investment options and may, at any time, in its discretion, change the target allocations or deviate from the target allocations when it believes doing so is appropriate to pursue the Fund's investment objective. The Adviser may modify the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. The tables are presented for illustrative purposes only.

A brief description of the Underlying Funds can be found in Appendix A. Appendix A lists the Underlying Funds that each Fund may utilize as of the date of this Prospectus.

Additional Information About Risks

The Funds are subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure. Except as otherwise stated, references in this section to “the Fund” or “a Fund” may relate to the Fund, one or more Underlying Funds, or both. The risks described below may arise out of the Fund's direct investments or the Fund's investments in one or more of the Underlying Funds.

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Asset Allocation Risk. A Fund's investment performance depends upon the successful allocation of the Fund's assets among asset classes, geographical regions, industry sectors, and specific issuers and investments. There is no guarantee that a Fund's allocation techniques and decisions will produce the desired results. It is possible to lose money on an investment in a Fund as a result of these allocation decisions.

Below Investment-Grade Securities Risk. Securities rated below investment-grade and unrated securities of comparable credit quality (commonly known as “high-yield bonds” or “junk bonds”) lack strong investment-grade characteristics, are considered predominantly speculative with respect to the issuer's continuing ability to make principal and interest payments, and are subject to greater levels of credit, liquidity and market risk than higher-rated securities. They can involve a substantially greater risk of default than higher-rated securities, and their values can decline significantly over short periods of time. Issuers of lower-quality debt securities may have substantially greater risk of insolvency or bankruptcy than issuers of higher-quality debt securities. In the event the issuer of a debt security held by a Fund defaults on its payments or becomes insolvent or bankrupt, the Fund may not receive the return it was promised on the investment and could lose its entire investment. The lower ratings of junk bonds reflect a greater possibility that actual or perceived adverse changes in the financial condition of the issuer or in general economic conditions, or an unanticipated rise in interest rates, may impair the ability of the issuer to make payments of interest and principal. If this were to occur, the values of such securities held by a Fund may fall substantially and a Fund could lose some or all of the value of its investment. Lower-quality debt securities tend to be more sensitive to adverse news about the issuer, or the market or economy in general, than higher quality debt securities. The market for lower quality debt securities can be less liquid than for higher quality debt securities, especially during periods of recession or general market decline, which could make it difficult at times for a Fund to sell certain securities at prices used in calculating a Fund's NAV. These securities may have significant volatility.

Call/Prepayment Risk. Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by a Fund earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by a Fund are prepaid. In any such case, a Fund may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Fund's income.

Commodities Risk. Commodity prices can have significant volatility, and exposure to commodities can cause the NAV of Fund Shares to decline or fluctuate in a rapid and unpredictable manner. The values of physical commodities may be affected by changes in overall market movements, real or perceived inflationary trends, commodity index volatility, changes in interest rates or currency exchange rates, population growth and changing demographics, international economic, political and regulatory developments, and factors affecting a particular region, industry or commodity, such as drought, floods, or other weather conditions, livestock disease, changes in storage costs, trade embargoes, competition from substitute products, transportation bottlenecks or shortages, fluctuations in supply and demand, and tariffs. Also, a liquid secondary market may not exist for certain commodity investments, which may make it difficult for the Fund to sell them at a desirable price or at the price at which it is carrying them. The commodity markets are subject to temporary distortions or other disruptions due to, among other factors, lack of liquidity, the participation of speculators, and government regulation and other actions.

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Fund. Further, a Fund may be subject to “bail-in” risk under applicable law whereby, if required by the financial institution's authority, the financial institution's liabilities could be written down, eliminated or converted into equity or an alternative instrument of ownership. A bail-in of a financial institution may result in a reduction in value of some or all of its securities and, if a Fund holds such securities or has entered into a transaction with such a financial security when a bail-in occurs, such Fund may also be similarly impacted.

Credit Risk. Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by a Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

Currency Risk. Investments in issuers in different countries are often denominated in currencies other than the U.S. dollar. Changes in the values of those currencies relative to the U.S. dollar may have a positive or negative effect on the values of a Fund's investments denominated in those currencies. The values of other currencies relative to the U.S. dollar may fluctuate in response to, among other factors, interest rate changes, intervention (or failure to intervene) by national governments, central banks, or supranational entities such as the International Monetary Fund, the imposition of currency controls, and other political or regulatory developments. Currency values can decrease significantly both in the short term and over the long term in response to these and other developments. Continuing uncertainty as to the status of the Euro and the Economic and Monetary Union of the European Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU, or any continued uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's portfolio investments.

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is denominated in a different currency than its underlying securities, a Fund will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. There may be less publicly available information regarding the issuer of the securities underlying a depositary receipt than if those securities were traded directly in U.S. securities markets. Depositary receipts may or may not be sponsored by the issuers of the underlying securities, and information regarding issuers of securities underlying unsponsored depositary receipts may be more limited than for sponsored depositary receipts. The values of depositary receipts may decline for a number of reasons relating to the issuers or sponsors of the depositary receipts, including, but not limited to, insolvency of the issuer or sponsor. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based. To the extent the Fund invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

Emerging Markets Risk. Investments in emerging markets are generally subject to a greater risk of loss than investments in developed markets. This may be due to, among other things, the possibility of greater market volatility, lower trading volume and liquidity, greater risk of expropriation, nationalization, and social, political and economic instability, greater reliance on a few industries, international trade or revenue from particular commodities, less developed accounting, legal and regulatory systems, higher levels of inflation, deflation or currency devaluation, greater risk of market shut down, and more significant governmental limitations on investment policy as compared to those typically found in a developed market. The Public Company Accounting Oversight Board, which regulates auditors of U.S. public companies, is unable to inspect audit work papers in certain foreign countries. Investors in foreign countries often have limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the U.S. Securities and Exchange Commission, the U.S. Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited. In addition, issuers (including governments) in emerging market countries may have less financial stability than in other countries. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. A Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. There is also the potential for unfavorable action such as embargo and acts of war. As a result, there will tend to be an increased risk of price volatility in investments in emerging market countries, which may be magnified by currency fluctuations relative to the U.S. dollar. Settlement and asset custody practices for transactions in emerging markets may differ from those in developed markets. Such differences may include possible delays in settlement and certain settlement practices, such as delivery of securities prior to receipt of payment, which increase the likelihood of a “failed settlement.” Failed settlements can result in losses. For these and other reasons, investments in emerging markets are often considered speculative.

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the issuer's goods or services. The values of equity securities also may decline due to general industry or market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, or adverse investor sentiment generally. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

Income Risk. A Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by a Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Fund may limit the Fund's ability to achieve its objective.

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a Fund's return and that of the Index. Changes in the composition of the Index and regulatory requirements also may impact a Fund's ability to match the return of the Index. The Adviser may apply one or more “screens” or investment techniques to refine or limit the number or types of issuers included in the Index in which a Fund may invest. Application of such screens or techniques may result in investment performance below that of the Index and may not produce results expected by the Adviser. Index tracking risk may be heightened during times of increased market volatility or other unusual market conditions.

Inflation Risk. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the values of a Fund's assets can decline. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy (or expectations that domestic or global economic policies will change), and the Fund's investments may not keep pace with inflation, which may result in losses to Fund investors or adversely affect the real value of shareholders' investments in the Fund.

Inflation-Indexed Securities Risk. The principal amount of an inflation-indexed security typically increases with inflation and decreases with deflation, as measured by a specified index. It is possible that, in a period of declining inflation rates, a Fund could receive at maturity less than the initial principal amount of an inflation-indexed security. Although the holders of U.S. TIPS receive no less than the par value of the security at maturity, if a Fund purchases U.S. TIPS in the secondary market whose principal values have previously been adjusted upward and there is a period of subsequent declining inflation rates, a Fund may receive at maturity less than it invested. Depending on the changes in inflation rates during the period a Fund holds an inflation-indexed security, a Fund may earn less on the security than on a conventional bond. Changes in the values of inflation-indexed securities may be difficult to predict, and it is possible that an investment in such securities will have an effect different from that anticipated by the Adviser. The principal amounts of inflation-indexed securities are typically only adjusted periodically, and changes in the values of the securities may only approximately reflect changes in inflation rates and may occur substantially after the changes in inflation rates in question occur.

Information Technology Sector Risk (principal risk for the Target Retirement 2050 Fund, Target Retirement 2055 Fund, Target Retirement 2060 Fund and Target Retirement 2065 Fund). Market or economic factors impacting information technology companies could have a major effect on the value of the Fund's investments. The value of stocks of information technology companies is particularly vulnerable to rapid changes in technology product cycles, rapid product obsolescence, government regulation and competition, both domestically and internationally, including competition from foreign competitors with lower production costs. Like other technology companies, information technology companies may have limited product lines, markets, financial resources or personnel. Stocks of technology companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Information technology companies are heavily dependent on patent and intellectual property rights, the loss or impairment of which may adversely affect profitability. Additionally, companies in the information technology sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel.

IPO Risk. Each Fund may at times have the opportunity to invest in securities offered in initial public offerings (“IPOs”). IPOs involve companies that have no public operating history and therefore entail more risk than established public companies. The prices of securities offered in IPOs can have significant volatility and a Fund may lose money on an invest-

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ment in such securities. IPOs may not be available to a Funds at all times, and a Funds may not always invest in IPOs offered to it. Investments in IPOs may have a substantial beneficial effect on a Fund's investment performance. A Fund's investment return earned during a period of substantial investment in IPOs may not be sustained during other periods when a Fund makes more limited, or no, investments in IPOs. There can be no assurance that the Funds will have the opportunity to invest in IPOs that are made available to other clients of the Adviser.

Large Shareholder Risk. To the extent a large proportion of the shares of a Fund are highly concentrated or held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, a Fund is subject to the risk that these shareholders will purchase or redeem Fund shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of a Fund to conduct its investment program. For example, they could require a Fund to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to shareholders, or a Fund may be required to sell its more liquid portfolio investments to meet a large redemption, in which case a Fund's remaining assets may be less liquid, more volatile, and more difficult to price. A Fund may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

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market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity a Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

Longevity Risk. This is the risk that you will outlive your retirement assets.

Management Risk. Each Fund is actively managed. The Adviser's judgments about the attractiveness, relative value, or potential appreciation of a particular sector, security, commodity or investment strategy may prove to be incorrect, and may cause a Fund to incur losses. There can be no assurance that the Adviser's investment techniques and decisions will produce the desired results.

Market Disruption and Geopolitical Risk. A Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of a Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in actual or perceived creditworthiness of issuers and general market liquidity. Even if general economic conditions do not change, the value of an investment in a Fund could decline if the particular industries, sectors or companies in which the Fund invests do not perform well or are adversely affected by events. Further, legal, political, regulatory and tax changes also may cause fluctuations in markets and securities prices. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on a Fund and its investments.

Modeling Risk. The Adviser uses quantitative models in an effort to enhance returns and manage risk. Any imperfections, errors or limitations in these models could limit any benefit to a Fund from the use of the models, or could result in incorrect outputs or in investment outcomes different from or opposite to those expected or desired by the Adviser. These models may make simplifying assumptions that limit their effectiveness and may draw from historical data that does not adequately identify or reflect factors necessary to an appropriate or useful output. There can be no assurance that the models will behave as expected in all market conditions. In addition, computer programming used to create quantitative models, or the data on which such models operate, might contain one or more errors. Such errors might never be detected, or might be detected only after a Fund has sustained a loss (or reduced performance) related to such errors.

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have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invest, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Non-U.S. Securities Risk. Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Because non-U.S. securities are typically denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets, to the extent they are non-U.S. dollar denominated, may be affected favorably or unfavorably by currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Fund invests could cause the Fund's investments in that country to experience gains or losses.

Real Estate Sector Risk. There are special risks associated with investment in securities of companies engaged in real property markets, including without limitation Real estate investment trusts (“REITs”) and real estate operating companies. An investment in a real property company may be subject to risks similar to those associated with direct ownership of real estate, including, by way of example, the possibility of declines in the value of real estate, losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, environmental liability, zoning laws, regulatory limitations on rents, property taxes, and operating expenses. An investment in a real property company is subject to additional risks, such as poor performance by the manager of the real property company, adverse changes in tax laws, difficulties in valuing and disposing of real estate, and the effect of general declines in stock prices. Some real property companies have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a real property company may contain provisions that make changes in control of the company difficult and time-consuming. As a shareholder in a real property company, a Fund, and indirectly a Fund's shareholders, would bear their ratable shares of the real property company's expenses and would at the same time continue to pay their own fees and expenses.

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REIT Risk. REITs are subject to the risks associated with investing in the securities of real property companies. In particular, REITs may be affected by changes in the values of the underlying properties that they own or operate. Further, REITs are dependent upon specialized management skills, and their investments may be concentrated in relatively few properties, or in a small geographic area or a single property type. REITs are also subject to heavy cash flow dependency and, as a result, are particularly reliant on the proper functioning of capital markets, as well as defaults by borrowers and self-liquidation. A variety of economic and other factors may adversely affect a lessee's ability to meet its obligations to a REIT. In the event of a default by a lessee, the REIT may experience delays in enforcing its rights as a lessor and may incur substantial costs associated with protecting its investments. In addition, a REIT could possibly fail to qualify for favorable tax treatment under the Internal Revenue Code of 1986, as amended (the “Code”), or to maintain its exemptions from registration under the U.S. Investment Company Act of 1940, as amended (the “1940 Act”), which could have adverse consequences for a Fund. Investments in REITs are also subject to the risks affecting equity markets generally.

Reinvestment Risk. Income from a Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by a Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

Restricted Securities Risk. A Fund may hold securities that have not been registered for sale to the public under the U.S. federal securities laws pursuant to an exemption from registration. These securities may be less liquid than securities registered for sale to the general public. The liquidity of a restricted security may be affected by a number of factors, including, among others: (i) the creditworthiness of the issuer; (ii) the frequency of trades and quotes for the security; (iii) the number of dealers willing to purchase or sell the security and the number of other potential purchasers; (iv) dealer undertakings to make a market in the security; (v) the nature of any legal restrictions governing trading in the security; and (vi) the nature of the security and the nature of marketplace trades. There can be no assurance that a liquid trading market will exist at any time for any particular restricted security. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

Risk of Investment in Other Pools. When a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

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from it. A Fund may be required to borrow monies it had otherwise expected to receive in connection with the settlement of securities sold by it, in order to meet its obligations to others. Limits on the ability of a Fund to purchase or sell securities due to settlement delays could increase any variance between a Fund's performance and that of its benchmark index.

Small-, Mid- and Micro-Capitalization Securities Risk. The securities of small-, mid- and micro-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of smaller companies may trade less frequently and in smaller volumes than more widely held securities. The prices of these securities may fluctuate more sharply than those of other securities, and a Fund may experience some difficulty in establishing or closing out positions in these securities at prevailing market prices. There may be less publicly available information about the issuers of these securities or less market interest in these securities than in the case of larger companies, both of which can cause significant price volatility. Some securities of smaller issuers may be illiquid or may be restricted as to resale. A Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet a Fund's obligations. Returns on investments in securities of small-, mid- and micro-capitalization companies could trail the returns on investments in securities of larger companies.

Target Date Assumption Risk. This is the risk that assumptions and forecasts used by SSGA FM in developing the Fund's asset allocation glide path are not in line with actual future investment returns and participant savings activities, which could result in losses near, at, or after the target date year or could result in the Fund not providing adequate income at and through retirement.

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remained at a historically high level. Although high debt levels do not necessarily indicate or cause economic problems, they may create certain systemic risks if sound debt management practices are not implemented. A high national debt level may increase market pressures to meet government funding needs, which may drive debt cost higher and cause a country to sell additional debt, thereby increasing refinancing risk. A high national debt also raises concerns that a government will not be able to make principal or interest payments when they are due. In the worst case, unsustainable debt levels can cause a decline in the value of the dollar (which may lead to inflation), and can prevent the U.S. government from implementing effective counter-cyclical fiscal policy in economic downturns. On August 5, 2011, Standard & Poor's Ratings Services downgraded U.S. Treasury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

Valuation Risk. Some portfolio holdings, potentially a large portion of a Fund's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. Technological issues or other service disruption issues involving third-party service providers may cause a Fund to value its investments incorrectly. In addition, there is no assurance that a Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that a Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by a Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

When-Issued, TBA and Delayed Delivery Securities Risk. A Fund may purchase securities on a when-issued, to be announced (“TBA”) or delayed delivery basis and may purchase securities on a forward commitment basis. The purchase price of the securities is typically fixed at the time of the commitment, but delivery and payment can take place a month or more after the date of the commitment. The prices of the securities so purchased or sold are subject to market fluctuations. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued, TBA, delayed delivery, or forward commitment basis may give rise to investment leverage, and may result in increased volatility of a Fund's net asset value. Default by, or bankruptcy of, a counterparty to a when-issued, TBA or delayed delivery transaction would expose a Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Financial Industry Regulatory Authority, Inc. rules impose mandatory margin requirements for certain types of when-issued, TBA delayed delivery or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization which may increase the cost of such transactions and impose added operational complexity.

Additional Information About Non-Principal Investment Strategies and Risks

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on which it enters into transactions with the Adviser or its affiliates will be the most favorable available in the market generally or as favorable as the rates the Adviser or its affiliates make available to other clients. Because of its financial interest, the Adviser will have an incentive to enter into transactions or arrangements on behalf of a Fund with itself or its affiliates in circumstances where it might not have done so in the absence of that interest, provided that the Adviser will comply with applicable regulatory requirements.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund and its service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invest, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

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Portfolio Turnover Risk. A Fund may engage in frequent trading of its portfolio securities. Fund turnover generally involves a number of direct and indirect costs and expenses to a Fund, including, for example, brokerage commissions, dealer mark-ups and bid/asked spreads, and transaction costs on the sale of securities and reinvestment in other securities. The costs related to increased portfolio turnover have the effect of reducing a Fund's investment return, and the sale of securities by a Fund may result in the realization of taxable capital gains, including short-term capital gains, which are taxed to individuals as ordinary income.

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Temporary Defensive Positions. In response to actual or perceived adverse market, economic, political, or other conditions, a Fund may (but will not necessarily), without notice, depart from its principal investment strategies by temporarily investing for defensive purposes. Temporary defensive positions may include, but are not limited to, cash, cash equivalents, U.S. government securities, repurchase agreements collateralized by such securities, money market funds, and high-quality debt investments. While investing defensively, a Fund may maintain a substantial portion of its assets in cash, on which a Fund may earn little if any income. If a Fund invests for defensive purposes, it may not achieve its investment objective. In addition, the defensive strategy may not work as intended.

Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

SSGA FM serves as the investment adviser to each Fund and, subject to the oversight of the Board, is responsible for the investment management of each Fund. The Adviser provides an investment management program for each Fund and manages the investment of each Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the U.S. Securities and Exchange Commission (“SEC”) under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

Each Fund has entered into an investment advisory agreement with the Adviser, pursuant to which the Adviser will manage the Fund's assets for compensation paid at the annual rate, set forth below, of the Fund's average daily net assets.

Target Retirement 2020 Fund	0.05%
Target Retirement 2025 Fund	0.05%
Target Retirement 2030 Fund	0.05%
Target Retirement 2035 Fund	0.05%
Target Retirement 2040 Fund	0.05%
Target Retirement 2045 Fund	0.05%
Target Retirement 2050 Fund	0.05%
Target Retirement 2055 Fund	0.05%
Target Retirement 2060 Fund	0.05%
Target Retirement 2065 Fund	0.05%
Target Retirement Fund	0.05%

Total Annual Fund Operating Expense Waivers. SSGA FM, as the investment adviser to each Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by a Fund, and/or (ii) to reimburse a Fund to the extent that Total Annual Fund Operating Expenses (exclusive of nonrecurring account fees, interest, taxes, extraordinary expenses, and distribution, shareholder servicing, and sub-transfer agency fees) exceed 0.09% of average daily net assets on an annual basis. These waiver and/or reimbursement arrangements may not be terminated prior to April 30, 2023 except with approval of the Funds' Board of Trustees.

A discussion regarding the Board's consideration of the Target Retirement 2020 Fund's, Target Retirement 2025 Fund's, Target Retirement 2030 Fund's, Target Retirement 2035 Fund's, Target Retirement 2040 Fund's, Target Retirement 2045 Fund's, Target Retirement 2050 Fund's, Target Retirement 2055 Fund's, Target Retirement 2060 Fund's, Target Retirement 2065 Fund's, and Target Retirement Fund's Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

Portfolio Management

The Adviser manages the Funds using a team of investment professionals. The team approach is used to create an environment that encourages the flow of investment ideas. The portfolio managers within the team work together in a cohesive manner to develop and enhance techniques that drive the investment process for the respective investment strategy. This approach requires portfolio managers to share a variety of responsibilities, including investment strategy and analysis, while retaining responsibility for the implementation of the strategy within any particular portfolio. The approach also enables the team to draw upon the resources of other groups within SSGA. Each portfolio management team is overseen by the SSGA Investment Committee.

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Key professionals involved in the day-to-day portfolio management of the Funds include the following:

Seamus Quinn, CFA, CAIA, is a Principal of SSGA and the Adviser and a Portfolio Manager in the Investment Solutions Group (ISG). He is responsible for the development and investment management of a variety of customized multi-asset class portfolios, including strategic, tactical, and exposure management strategies. Mr. Quinn joined SSGA in 2012 and has been part of ISG since 2017. Prior to joining ISG, Mr. Quinn was a portfolio analyst in the Fixed Income Operations team. Prior to his role at SSGA, Mr. Quinn worked at State Street Corporation as a fund accountant. Mr. Quinn holds a Bachelor of Science degree in Finance from the University of Massachusetts and a Master of Science in Finance from the Carroll School of Management at Boston College. He has earned the Chartered Financial Analyst (CFA) and the Chartered Alternative Investment Analyst (CAIA) designations and is a member of the CFA Institute, CFA Society Boston, Inc., and the CAIA Association.

Michael Narkiewicz is a Vice President of SSGA and the Adviser and a Senior Portfolio Manager in the Investment Solutions Group (ISG), where he is responsible for the development and investment management of a variety of customized multi-asset class portfolios, including strategic, tactical, and real asset strategies. Prior to his current role, Mr. Narkiewicz was a portfolio specialist within the Global Equity Beta Solutions Group. His responsibilities included investment research and analysis as well as product positioning and messaging across multiple index equity investment strategies. Before joining SSGA in 2013, Mr. Narkiewicz was a senior portfolio analyst at Shepherd Kaplan, a Boston based registered investment advisor, and an equity trader at Congress Asset Management Company. He holds a Bachelor of Science degree in Finance from Bentley University and a Master of Business Administration with a concentration in Finance from the D'Amore-McKim School of Business at Northeastern University.

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Funds is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator for each Fund for a fee that is paid by the Adviser. State Street also serves as custodian of each Fund for a separate fee that is paid by the Funds.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

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Shareholder Information

Determination of Net Asset Value

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

Choosing a Share Class

The Funds offer three classes of shares through this Prospectus: Class I, Class K and Class R3, available to you subject to the eligibility requirements set forth below.

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	Class I	Class K	Class R3
Availability	Limited to certain investors serviced through a Financial Intermediary receiving a fee from the fund for shareholder servicing or similar services.	Limited to certain investors, including certain financial institutions, qualified recordkeepers and employer-sponsored retirement plans.	Limited to certain investors, including certain financial institutions, qualified recordkeepers and employer-sponsored retirement plans.
Minimum Initial Investment	There is no minimum investment for Class I shares.	There is no minimum investment for Class K shares.	There is no minimum investment for Class R3 shares.
Maximum Investment	None.	None.	None.
Initial (Front-End) Sales Charge	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No.	No.	No.
Distribution and Service (Rule 12b-1) Fees	No.	No.	0.25% annual fee.
Redemption Fees	No.	No.	No.

Class I

Class I shares are available to the following categories of investors serviced through a Financial Intermediary receiving a fee from a Fund for shareholder servicing or similar services:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) that have entered into agreements with the Fund to purchase Class I shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund “supermarkets”;

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•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Defined contribution, defined benefit and other employer-sponsored employee benefit plans, whether or not qualified under the Code.

There is no minimum investment for Class I shares.

Class K

Class K shares are available to the following categories of investors:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) purchasing Fund Shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund "supermarkets";
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Qualified recordkeepers with an applicable agreement maintained with SSGA FD;
3.	Endowments and foundations, and defined contribution, defined benefit, and other employer-sponsored employee benefit plans, whether or not qualified under the Code;
4.	Certain other registered open-end investment companies whose shares are distributed by SSGA FD;
5.	Current or retired Directors or Trustees of the State Street Funds, officers and employees of SSGA, and any of its subsidiaries, such persons' spouses, and children under the age of 21, and trust accounts for which any of such person is a beneficiary;
6.	Qualified state tuition plans described in Section 529 of the Code and donor-advised charitable gift funds (subject to all applicable terms and conditions);
7.	Health Savings Accounts under Section 223 of the Code if such accounts are maintained by the Fund at an omnibus level;
8.	Collective investment trusts.

There is no minimum investment for Class K shares.

Class R3

Class R3 shares are not subject to any sales charge. Only certain investors are eligible to buy Class R3 shares. Your Financial Intermediary can help you determine whether you are eligible to purchase Class R3 shares.

Class R3 shares are available to the following categories of investors:

1.	401(k), 403(b), 457, deferred compensation, defined benefit, money purchase pension and profit-sharing retirement plans that require recordkeeping and administrative services.
2.	They are not available in retail accounts or retail non-retirement accounts; Traditional and Roth IRAs, Coverdell Education Savings Accounts, SEPs, SARSEPs, and SIMPLE IRAs held in brokerage accounts; and 529 college savings plans.

There is no minimum investment for Class R3 shares.

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How to Initiate a Purchase Request

Investing in the State Street Funds Through a Financial Intermediary

Account Applications and Other Documents. You may find many of the forms necessary to open an account online or by calling or writing to the State Street Funds. See Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

How to Pay for a Purchase

By Check. You may send a check to make initial or additional purchases to your fund account. Make your check payable to “State Street Funds” and include the appropriate fund name and account number (e.g., “State Street Target Retirement 2020 Fund—a/c #xxx”) in the memo section of the check.

Trade Dates-Purchases

If your purchase request is not in good order, it may be rejected.

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For further information about purchase transactions, consult our website at www.ssga.com or see Contacting the State Street Funds.

Other Purchase Policies You Should Know

Redeeming Shares

By Telephone. You may call the State Street Funds to request a redemption of shares. See Contacting the State Street Funds.

By Mail. You may send a written request to the State Street Funds to redeem from a Fund account or to make an exchange. See Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

Trade Date-Redemptions

The trade date for any redemption request received in good order will depend on the day and time the State Street Funds receive your request in good order and the manner in which you are redeeming.

How to Receive Redemption Proceeds

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Other Redemption Policies that You Should Know

Address Changes. If your address of record has been changed within thirty (30) days of the redemption request, the request must be in writing and bear a medallion guarantee.

Significant/Unusual Economic or Market Activity. During periods of significant or unusual economic or market activity, you may encounter delays attempting to give instructions by phone.

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Exchanging Shares

Share Class Conversions

Frequent-Trading Limits

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As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;
•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Funds against harmful short-term trading; and
•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Service Options

Dividend and Capital Gain Distribution Option

Please refer to Dividends, Distributions and Tax Considerations below for additional information.

Automatic Withdrawal Plan

Telephone Redemptions and Exchanges

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Automatic Investment Plan

Additional Shareholder Information

Account Transfers

Responsibility for Fraud

Right to Change Policies

In addition to the rights expressly stated elsewhere in this Prospectus, the State Street Funds reserve the right, in the future, to:

1.	Alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, service, or privilege at any time;
2.	Accept initial purchases by telephone;
3.	Freeze any account and/or suspend account services if the State Street Funds has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if we reasonably believe a fraudulent transaction may occur or has occurred;
4.	Temporarily freeze any account and/or suspend account services upon initial notification to the State Street Funds of the death of the shareholder until the State Street Funds receive required documentation in good order;
5.	Alter, impose, discontinue, or waive any redemption fee, account service fee, or other fees charged to a group of shareholders; and
6.	Redeem an account or suspend account privileges, without the owner's permission to do so, in cases of threatening conduct or activity the State Street Funds believe to be suspicious, fraudulent, or illegal.

Unclaimed Property

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Dividends, Distributions and Tax Considerations

Distribution Options. You can choose from four different distribution options as indicated on the application:

•	Reinvestment Option—Dividends and capital gain distributions will be automatically reinvested in additional shares of a Fund. If you do not indicate a choice on the application, this option will be automatically assigned.
•	Income-Earned Option—Capital gain distributions will be automatically reinvested, but a check, direct deposit or wire will be sent for each dividend distribution.
•	Cash Option—A check, wire or direct deposit will be sent for each dividend and capital gain distribution.
•	Direct Dividends Option—Dividends and capital gain distributions will be automatically invested in another identically registered State Street Fund of the same share class.

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (800) 997-7327, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Tax Considerations

The following discussion is a summary of some important U.S. federal income tax considerations generally applicable to an investment in a Fund. Your investment in a Fund may have other tax implications. Please consult your tax advisor about federal, state, local, foreign or other tax laws applicable to you. Investors, including non-U.S. investors, may wish to consult the SAI tax section for additional disclosure. Each of the Funds seeks to achieve its investment objective by investing in a combination of Underlying Funds each of which intends to qualify and be treated as a regulated investment company for U.S. federal income tax purposes such that substantially all of the Funds' income will result from distributions from such Underlying Funds. Therefore, as applicable, and except as otherwise stated, references in this section to the assets owned or income earned by a Fund will include such assets and income of the corresponding Underlying Funds.

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properly reported by a Fund as derived from “qualified dividend income,” which will not include income from the Fund's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by both the shareholder and the Fund. Distributions are taxable to you even if they are paid from income or gains earned by a Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of a Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Fund's shares, and, in general, as capital gain thereafter.

A Fund's income from or proceeds of dispositions of its investments in non-U.S. assets may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. In certain instances, a Fund may be entitled to elect to pass through to its shareholders a credit (or deduction, for a shareholder that itemizes deductions and so chooses) for foreign taxes (if any) borne with respect to foreign securities income earned by the Fund. If the Fund so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the Fund. There can be no assurance that a Fund will make such election, even if it is eligible to do so. If a Fund does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Fund; in that case the foreign tax will nonetheless reduce the Fund's taxable income. Shareholders that are not subject to U.S. federal income tax, and those who invest in a Fund through tax-advantaged accounts (including those who invest through IRAs or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit or deduction passed through by the Fund. Under certain circumstances, if a Fund receives a refund of foreign taxes paid in respect of a prior year, the value of Fund Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Fund's foreign taxes for the current year could be reduced.

Certain of a Fund's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of a Fund's distributions, and may require the Fund to sell its investments at a time when it is not advantageous to do so.

A Fund's investments in the Underlying Funds may cause the tax treatment of the Fund's gains, losses and distributions to differ from the tax treatment that would apply if the Fund invested directly in the types of securities held by the Underlying Funds. As a result, investors may receive taxable distributions earlier and recognize higher amounts of capital gain or ordinary income than they otherwise would.

The U.S. Treasury and Internal Revenue Service (the “IRS”) generally require a Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Code, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

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Financial Intermediary Arrangements

Payments to Financial Intermediaries

The Funds have adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which a Fund may compensate SSGA FD (or others) for services in connection with the distribution of a Fund's Class R3 shares and for services provided to shareholders in that class (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.25% of each Fund's net assets attributable to its Class R3 shares. Because these fees are paid out of the assets of a Fund attributable to its Class R3 shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

A Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of that Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

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advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Funds' shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as Financial Industry Regulatory Authority, Inc.

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Financial Highlights

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2020 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$12.22	$11.39	$10.29	$11.34	$10.27
Income (loss) from investment operations:
Net investment income (loss) (a)	0.17	0.40	0.32	0.43	0.25
Net realized and unrealized gain (loss)	0.90	0.92	1.48	(0.90)	1.13
Total from investment operations	1.07	1.32	1.80	(0.47)	1.38
Distributions to shareholders from:
Net investment income	(0.28)	(0.25)	(0.33)	(0.29)	(0.23)
Net realized gains	(0.57)	(0.24)	(0.37)	(0.29)	(0.08)
Total distributions	(0.85)	(0.49)	(0.70)	(0.58)	(0.31)
Net asset value, end of period	$12.44	$12.22	$11.39	$10.29	$11.34
Total return (b)	8.79%	11.57%	17.53%	(4.17)%(c)	13.38%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$3,059	$41,182	$2,116	$1,798	$680
Ratios to Average Net Assets:
Total expenses (d)	0.40%	0.19%	0.15%	0.16%	0.15%
Net expenses (d)	0.24%	0.03%	0.01%	0.02%	0.01%
Net investment income (loss)	1.36%	3.39%	2.83%	3.85%	2.29%
Portfolio turnover rate	27%	37%	21%	22%	18%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (4.17)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2020 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$12.23	$11.40	$10.29	$11.34	$10.28
Income (loss) from investment operations:
Net investment income (loss) (a)	0.33	0.24	0.33	0.29	0.29
Net realized and unrealized gain (loss)	0.84	1.08	1.48	(0.76)	1.08
Total from investment operations	1.17	1.32	1.81	(0.47)	1.37
Distributions to shareholders from:
Net investment income	(0.32)	(0.25)	(0.33)	(0.29)	(0.23)
Net realized gains	(0.57)	(0.24)	(0.37)	(0.29)	(0.08)
Total distributions	(0.89)	(0.49)	(0.70)	(0.58)	(0.31)
Net asset value, end of period	$12.51	$12.23	$11.40	$10.29	$11.34
Total return (b)	9.55%	11.68%	17.55%	(4.16)%(c)	13.38%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$987,323	$820,938	$783,033	$847,142	$775,643
Ratios to Average Net Assets:
Total expenses (d)	0.13%	0.14%	0.14%	0.15%	0.15%
Net expenses (d)	(0.02)%(e)	(0.03)%(e)	(0.01)%(e)	0.01%	0.02%
Net investment income (loss)	2.53%	2.13%	2.88%	2.60%	2.67%
Portfolio turnover rate	27%	37%	21%	22%	18%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (4.16)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.
(e)	Due to the Fund waiving acquired Fund fees, the waiver exceeded total fund expenses.

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FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$13.06	$11.92	$10.53	$11.74	$10.33
Income (loss) from investment operations:
Net investment income (loss) (a)	0.15	0.50	0.37	0.23	0.26
Net realized and unrealized gain (loss)	1.16	1.26	1.81	(0.87)	1.45
Total from investment operations	1.31	1.76	2.18	(0.64)	1.71
Distributions to shareholders from:
Net investment income	(0.29)	(0.25)	(0.33)	(0.29)	(0.23)
Net realized gains	(0.58)	(0.37)	(0.46)	(0.28)	(0.07)
Total distributions	(0.87)	(0.62)	(0.79)	(0.57)	(0.30)
Net asset value, end of period	$13.50	$13.06	$11.92	$10.53	$11.74
Total return (b)	10.03%	14.66%	20.76%	(5.48)%(c)	16.54%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$5,301	$59,792	$2,019	$1,155	$2,232
Ratios to Average Net Assets:
Total expenses (d)	0.38%	0.19%	0.15%	0.15%	0.15%
Net expenses (d)	0.25%	0.04%	0.02%	0.05%	0.03%
Net investment income (loss)	1.11%	3.96%	3.10%	1.98%	2.36%
Portfolio turnover rate	24%	39%	27%	15%	10%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (5.48)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$13.09	$11.94	$10.55	$11.75	$10.34
Income (loss) from investment operations:
Net investment income (loss) (a)	0.36	0.27	0.33	0.31	0.30
Net realized and unrealized gain (loss)	1.06	1.50	1.85	(0.94)	1.41
Total from investment operations	1.42	1.77	2.18	(0.63)	1.71
Distributions to shareholders from:
Net investment income	(0.33)	(0.25)	(0.33)	(0.29)	(0.23)
Net realized gains	(0.58)	(0.37)	(0.46)	(0.28)	(0.07)
Total distributions	(0.91)	(0.62)	(0.79)	(0.57)	(0.30)
Net asset value, end of period	$13.60	$13.09	$11.94	$10.55	$11.75
Total return (b)	10.81%	14.84%	20.63%	(5.38)%(c)	16.52%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,738,831	$1,228,301	$1,035,188	$1,007,169	$830,080
Ratios to Average Net Assets:
Total expenses (d)	0.13%	0.14%	0.14%	0.14%	0.15%
Net expenses (d)	0.00%(e)	(0.01)%(f)	0.01%	0.04%	0.04%
Net investment income (loss)	2.57%	2.24%	2.83%	2.63%	2.63%
Portfolio turnover rate	24%	39%	27%	15%	10%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (5.38)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.
(e)	Amount is less than 0.005%.
(f)	Due to the Fund waiving acquired Fund fees, the waiver exceeded total fund expenses.

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STATE STREET TARGET RETIREMENT 2030 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$13.70	$12.26	$10.67	$11.98	$10.37
Income (loss) from investment operations:
Net investment income (loss) (a)	0.11	0.53	0.38	0.29	0.25
Net realized and unrealized gain (loss)	1.36	1.58	2.03	(1.05)	1.64
Total from investment operations	1.47	2.11	2.41	(0.76)	1.89
Distributions to shareholders from:
Net investment income	(0.27)	(0.24)	(0.32)	(0.27)	(0.23)
Net realized gains	(0.61)	(0.43)	(0.50)	(0.28)	(0.05)
Total distributions	(0.88)	(0.67)	(0.82)	(0.55)	(0.28)
Net asset value, end of period	$14.29	$13.70	$12.26	$10.67	$11.98
Total return (b)	10.76%	17.26%	22.55%	(6.24)%	18.27%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$8,838	$69,750	$2,837	$1,768	$1,716
Ratios to Average Net Assets:
Total expenses (c)	0.37%	0.19%	0.15%	0.15%	0.15%
Net expenses (c)	0.27%	0.08%	0.04%	0.07%	0.06%
Net investment income (loss)	0.74%	4.00%	3.12%	2.44%	2.25%
Portfolio turnover rate	22%	27%	30%	12%	7%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2030 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$13.72	$12.27	$10.69	$12.00	$10.38
Income (loss) from investment operations:
Net investment income (loss) (a)	0.35	0.27	0.33	0.29	0.28
Net realized and unrealized gain (loss)	1.21	1.86	2.07	(1.04)	1.62
Total from investment operations	1.56	2.13	2.40	(0.75)	1.90
Distributions to shareholders from:
Net investment income	(0.31)	(0.25)	(0.32)	(0.28)	(0.23)
Net realized gains	(0.61)	(0.43)	(0.50)	(0.28)	(0.05)
Total distributions	(0.92)	(0.68)	(0.82)	(0.56)	(0.28)
Net asset value, end of period	$14.36	$13.72	$12.27	$10.69	$12.00
Total return (b)	11.37%	17.24%	22.52%	(6.22)%	18.35%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,055,047	$1,367,241	$1,072,332	$960,339	$778,969
Ratios to Average Net Assets:
Total expenses (c)	0.12%	0.14%	0.14%	0.14%	0.15%
Net expenses (c)	0.03%	0.03%	0.03%	0.06%	0.06%
Net investment income (loss)	2.37%	2.13%	2.75%	2.43%	2.46%
Portfolio turnover rate	22%	27%	30%	12%	7%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2035 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.16	$12.54	$10.80	$12.18	$10.43
Income (loss) from investment operations:
Net investment income (loss) (a)	0.06	0.56	0.36	0.30	0.13
Net realized and unrealized gain (loss)	1.55	1.71	2.19	(1.14)	1.91
Total from investment operations	1.61	2.27	2.55	(0.84)	2.04
Distributions to shareholders from:
Net investment income	(0.26)	(0.24)	(0.30)	(0.26)	(0.22)
Net realized gains	(0.55)	(0.41)	(0.51)	(0.28)	(0.07)
Total distributions	(0.81)	(0.65)	(0.81)	(0.54)	(0.29)
Net asset value, end of period	$14.96	$14.16	$12.54	$10.80	$12.18
Total return (b)	11.38%	18.05%	23.62%	(6.88)%(c)	19.56%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$4,878	$49,518	$1,193	$442	$371
Ratios to Average Net Assets:
Total expenses (d)	0.38%	0.20%	0.21%	0.16%	0.17%
Net expenses (d)	0.29%	0.10%	0.12%	0.07%	0.07%
Net investment income (loss)	0.41%	4.14%	2.95%	2.49%	1.10%
Portfolio turnover rate	19%	22%	28%	13%	6%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (6.88)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2035 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.21	$12.57	$10.83	$12.21	$10.44
Income (loss) from investment operations:
Net investment income (loss) (a)	0.34	0.26	0.32	0.28	0.27
Net realized and unrealized gain (loss)	1.39	2.03	2.24	(1.12)	1.79
Total from investment operations	1.73	2.29	2.56	(0.84)	2.06
Distributions to shareholders from:
Net investment income	(0.30)	(0.24)	(0.31)	(0.26)	(0.22)
Net realized gains	(0.55)	(0.41)	(0.51)	(0.28)	(0.07)
Total distributions	(0.85)	(0.65)	(0.82)	(0.54)	(0.29)
Net asset value, end of period	$15.09	$14.21	$12.57	$10.83	$12.21
Total return (b)	12.18%	18.19%	23.61%	(6.85)%(c)	19.73%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,863,635	$1,215,824	$907,369	$796,187	$584,717
Ratios to Average Net Assets:
Total expenses (d)	0.13%	0.14%	0.15%	0.15%	0.17%
Net expenses (d)	0.04%	0.04%	0.05%	0.07%	0.08%
Net investment income (loss)	2.26%	2.03%	2.60%	2.30%	2.34%
Portfolio turnover rate	19%	22%	28%	13%	6%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (6.85)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2040 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.35	$12.65	$10.79	$12.26	$10.39
Income (loss) from investment operations:
Net investment income (loss) (a)	0.02	0.58	0.29	0.31	0.24
Net realized and unrealized gain (loss)	1.67	1.79	2.37	(1.23)	1.91
Total from investment operations	1.69	2.37	2.66	(0.92)	2.15
Distributions to shareholders from:
Net investment income	(0.26)	(0.23)	(0.30)	(0.26)	(0.23)
Net realized gains	(0.59)	(0.44)	(0.50)	(0.29)	(0.05)
Total distributions	(0.85)	(0.67)	(0.80)	(0.55)	(0.28)
Net asset value, end of period	$15.19	$14.35	$12.65	$10.79	$12.26
Total return (b)	11.75%	18.70%	24.64%	(7.46)%(c)	20.59%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,991	$51,116	$1,398	$1,247	$912
Ratios to Average Net Assets:
Total expenses (d)	0.39%	0.20%	0.17%	0.19%	0.17%
Net expenses (d)	0.32%	0.10%	0.07%	0.09%	0.07%
Net investment income (loss)	0.12%	4.25%	2.33%	2.50%	2.14%
Portfolio turnover rate	19%	19%	32%	11%	6%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (7.46)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2040 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.36	$12.66	$10.79	$12.27	$10.40
Income (loss) from investment operations:
Net investment income (loss) (a)	0.35	0.25	0.32	0.28	0.26
Net realized and unrealized gain (loss)	1.54	2.12	2.35	(1.21)	1.89
Total from investment operations	1.89	2.37	2.67	(0.93)	2.15
Distributions to shareholders from:
Net investment income	(0.30)	(0.23)	(0.30)	(0.26)	(0.23)
Net realized gains	(0.59)	(0.44)	(0.50)	(0.29)	(0.05)
Total distributions	(0.89)	(0.67)	(0.80)	(0.55)	(0.28)
Net asset value, end of period	$15.36	$14.36	$12.66	$10.79	$12.27
Total return (b)	13.15%	18.79%	24.66%	(7.52)%(c)	20.69%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,677,750	$1,076,641	$778,976	$636,762	$458,132
Ratios to Average Net Assets:
Total expenses (d)	0.13%	0.15%	0.16%	0.16%	0.17%
Net expenses (d)	0.05%	0.05%	0.05%	0.07%	0.07%
Net investment income (loss)	2.23%	1.94%	2.63%	2.24%	2.30%
Portfolio turnover rate	19%	19%	32%	11%	6%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (7.52)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2045 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.58	$12.72	$10.77	$12.29	$10.36
Income (loss) from investment operations:
Net investment income (loss) (a)	0.03	0.58	0.29	0.33	0.20
Net realized and unrealized gain (loss)	1.88	1.87	2.45	(1.31)	2.02
Total from investment operations	1.91	2.45	2.74	(0.98)	2.22
Distributions to shareholders from:
Net investment income	(0.28)	(0.22)	(0.30)	(0.26)	(0.24)
Net realized gains	(0.49)	(0.37)	(0.49)	(0.28)	(0.05)
Total distributions	(0.77)	(0.59)	(0.79)	(0.54)	(0.29)
Net asset value, end of period	$15.72	$14.58	$12.72	$10.77	$12.29
Total return (b)	13.08%	19.26%	25.45%	(7.96)%(c)	21.45%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,357	$23,059	$962	$787	$762
Ratios to Average Net Assets:
Total expenses (d)	0.39%	0.21%	0.21%	0.20%	0.21%
Net expenses (d)	0.30%	0.10%	0.09%	0.08%	0.06%
Net investment income (loss)	0.17%	4.27%	2.34%	2.68%	1.73%
Portfolio turnover rate	17%	18%	32%	11%	5%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (7.96)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2045 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.58	$12.72	$10.77	$12.29	$10.36
Income (loss) from investment operations:
Net investment income (loss) (a)	0.37	0.25	0.32	0.28	0.28
Net realized and unrealized gain (loss)	1.65	2.21	2.42	(1.26)	1.94
Total from investment operations	2.02	2.46	2.74	(0.98)	2.22
Distributions to shareholders from:
Net investment income	(0.32)	(0.23)	(0.30)	(0.26)	(0.24)
Net realized gains	(0.49)	(0.37)	(0.49)	(0.28)	(0.05)
Total distributions	(0.81)	(0.60)	(0.79)	(0.54)	(0.29)
Net asset value, end of period	$15.79	$14.58	$12.72	$10.77	$12.29
Total return (b)	13.83%	19.28%	25.49%	(7.94)%(c)	21.45%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,409,868	$847,354	$587,488	$465,425	$300,444
Ratios to Average Net Assets:
Total expenses (d)	0.14%	0.16%	0.17%	0.19%	0.21%
Net expenses (d)	0.05%	0.05%	0.05%	0.07%	0.07%
Net investment income (loss)	2.32%	1.93%	2.62%	2.29%	2.39%
Portfolio turnover rate	17%	18%	32%	11%	5%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (7.94)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2050 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.48	$12.60	$10.70	$12.24	$10.33
Income (loss) from investment operations:
Net investment income (loss) (a)	0.00(b)	0.61	0.28	0.37	0.15
Net realized and unrealized gain (loss)	1.90	1.87	2.47	(1.37)	2.06
Total from investment operations	1.90	2.48	2.75	(1.00)	2.21
Distributions to shareholders from:
Net investment income	(0.28)	(0.22)	(0.29)	(0.26)	(0.25)
Net realized gains	(0.48)	(0.38)	(0.56)	(0.28)	(0.05)
Total distributions	(0.76)	(0.60)	(0.85)	(0.54)	(0.30)
Net asset value, end of period	$15.62	$14.48	$12.60	$10.70	$12.24
Total return (c)	13.12%	19.67%	25.76%	(8.14)%	21.30%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,596	$24,016	$448	$374	$240
Ratios to Average Net Assets:
Total expenses (d)	0.41%	0.24%	0.25%	0.25%	0.25%
Net expenses (d)	0.31%	0.10%	0.09%	0.08%	0.06%
Net investment income (loss)	0.02%	4.48%	2.32%	3.05%	1.34%
Portfolio turnover rate	17%	16%	41%	11%	5%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Amount is less than $0.005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2050 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.49	$12.60	$10.70	$12.24	$10.33
Income (loss) from investment operations:
Net investment income (loss) (a)	0.38	0.25	0.34	0.28	0.27
Net realized and unrealized gain (loss)	1.70	2.24	2.42	(1.28)	1.94
Total from investment operations	2.08	2.49	2.76	(1.00)	2.21
Distributions to shareholders from:
Net investment income	(0.32)	(0.22)	(0.30)	(0.26)	(0.25)
Net realized gains	(0.48)	(0.38)	(0.56)	(0.28)	(0.05)
Total distributions	(0.80)	(0.60)	(0.86)	(0.54)	(0.30)
Net asset value, end of period	$15.77	$14.49	$12.60	$10.70	$12.24
Total return (b)	14.37%	19.76%	25.81%	(8.13)%	21.42%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,021,959	$587,556	$380,668	$300,431	$212,217
Ratios to Average Net Assets:
Total expenses (c)	0.15%	0.19%	0.21%	0.23%	0.25%
Net expenses (c)	0.05%	0.05%	0.05%	0.07%	0.07%
Net investment income (loss)	2.42%	1.98%	2.74%	2.30%	2.37%
Portfolio turnover rate	17%	16%	41%	11%	5%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2055 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.72	$12.68	$10.70	$12.25	$10.32
Income (loss) from investment operations:
Net investment income (loss) (a)	0.01	0.63	0.33	0.31	0.11
Net realized and unrealized gain (loss)	1.95	1.86	2.41	(1.29)	2.11
Total from investment operations	1.96	2.49	2.74	(0.98)	2.22
Distributions to shareholders from:
Net investment income	(0.28)	(0.22)	(0.30)	(0.25)	(0.24)
Net realized gains	(0.42)	(0.23)	(0.46)	(0.32)	(0.05)
Total distributions	(0.70)	(0.45)	(0.76)	(0.57)	(0.29)
Net asset value, end of period	$15.98	$14.72	$12.68	$10.70	$12.25
Total return (b)	13.32%	19.60%	25.65%	(7.93)%(c)	21.60%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$715	$8,940	$241	$130	$105
Ratios to Average Net Assets:
Total expenses (d)	0.44%	0.32%	0.30%	0.40%	0.52%
Net expenses (d)	0.31%	0.09%	0.05%	0.07%	0.06%
Net investment income (loss)	0.05%	4.61%	2.69%	2.53%	0.95%
Portfolio turnover rate	15%	18%	42%	16%	7%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (7.93)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET TARGET RETIREMENT 2055 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.70	$12.66	$10.68	$12.23	$10.31
Income (loss) from investment operations:
Net investment income (loss) (a)	0.40	0.26	0.35	0.30	0.31
Net realized and unrealized gain (loss)	1.71	2.23	2.39	(1.28)	1.90
Total from investment operations	2.11	2.49	2.74	(0.98)	2.21
Distributions to shareholders from:
Net investment income	(0.33)	(0.22)	(0.30)	(0.25)	(0.24)
Net realized gains	(0.42)	(0.23)	(0.46)	(0.32)	(0.05)
Total distributions	(0.75)	(0.45)	(0.76)	(0.57)	(0.29)
Net asset value, end of period	$16.06	$14.70	$12.66	$10.68	$12.23
Total return (b)	14.31%	19.65%	25.70%	(7.94)%(c)	21.53%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$641,834	$323,975	$195,598	$132,520	$81,529
Ratios to Average Net Assets:
Total expenses (d)	0.18%	0.27%	0.30%	0.40%	0.51%
Net expenses (d)	0.05%	0.04%	0.05%	0.07%	0.07%
Net investment income (loss)	2.52%	2.05%	2.86%	2.49%	2.67%
Portfolio turnover rate	15%	18%	42%	16%	7%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (7.94)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2060 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.69	$12.53	$10.28	$11.91	$10.09
Income (loss) from investment operations:
Net investment income (loss) (a)	0.05	0.59	0.29	0.30	0.15
Net realized and unrealized gain (loss)	1.97	1.87	2.37	(1.27)	2.01
Total from investment operations	2.02	2.46	2.66	(0.97)	2.16
Distributions to shareholders from:
Net investment income	(0.29)	(0.22)	(0.28)	(0.24)	(0.23)
Net realized gains	(0.36)	(0.08)	(0.13)	(0.42)	(0.11)
Total distributions	(0.65)	(0.30)	(0.41)	(0.66)	(0.34)
Net asset value, end of period	$16.06	$14.69	$12.53	$10.28	$11.91
Total return (b)	13.75%	19.61%	25.86%	(8.13)%	21.45%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$633	$3,458	$163	$121	$103
Ratios to Average Net Assets:
Total expenses (c)	0.50%	0.54%	0.85%	1.56%	3.13%
Net expenses (c)	0.28%	0.09%	0.04%	0.06%	0.06%
Net investment income (loss)	0.33%	4.41%	2.42%	2.55%	1.31%
Portfolio turnover rate	13%	25%	29%	38%	18%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2060 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$14.69	$12.53	$10.28	$11.91	$10.08
Income (loss) from investment operations:
Net investment income (loss) (a)	0.43	0.27	0.39	0.34	0.33
Net realized and unrealized gain (loss)	1.68	2.19	2.27	(1.31)	1.84
Total from investment operations	2.11	2.46	2.66	(0.97)	2.17
Distributions to shareholders from:
Net investment income	(0.33)	(0.22)	(0.28)	(0.24)	(0.23)
Net realized gains	(0.36)	(0.08)	(0.13)	(0.42)	(0.11)
Total distributions	(0.69)	(0.30)	(0.41)	(0.66)	(0.34)
Net asset value, end of period	$16.11	$14.69	$12.53	$10.28	$11.91
Total return (b)	14.34%	19.63%	25.87%	(8.13)%	21.57%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$314,182	$137,392	$74,373	$25,829	$12,141
Ratios to Average Net Assets:
Total expenses (c)	0.28%	0.49%	0.84%	1.56%	3.07%
Net expenses (c)	0.05%	0.04%	0.04%	0.06%	0.07%
Net investment income (loss)	2.68%	2.12%	3.33%	2.87%	2.94%
Portfolio turnover rate	13%	25%	29%	38%	18%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2065 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	For the Period 3/30/20*- 12/31/20
Net asset value, beginning of period	$13.69	$10.00
Income (loss) from investment operations:
Net investment income (loss) (a)	0.31	0.19
Net realized and unrealized gain (loss)	1.62	4.13
Total from investment operations	1.93	4.32
Distributions to shareholders from:
Net investment income	(0.26)	(0.23)
Net realized gains	(0.14)	(0.40)
Total distributions	(0.40)	(0.63)
Net asset value, end of period	$15.22	$13.69
Total return (b)	14.09%	43.15%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$178	$137
Ratios to Average Net Assets:
Total expenses (c)	1.45%	12.01%(d)
Net expenses (c)	0.25%	0.22%(d)
Net investment income (loss)	2.05%	2.08%(d)
Portfolio turnover rate	20%	86%(e)

*	Commencement of operations.
(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.
(d)	Annualized.
(e)	Not annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT 2065 FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	For the Period 3/30/20*- 12/31/20
Net asset value, beginning of period	$13.69	$10.00
Income (loss) from investment operations:
Net investment income (loss) (a)	0.61	0.45
Net realized and unrealized gain (loss)	1.36	3.88
Total from investment operations	1.97	4.33
Distributions to shareholders from:
Net investment income	(0.29)	(0.24)
Net realized gains	(0.14)	(0.40)
Total distributions	(0.43)	(0.64)
Net asset value, end of period	$15.23	$13.69
Total return (b)	14.39%	43.34%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$43,241	$3,557
Ratios to Average Net Assets:
Total expenses (c)	1.25%	11.81%(d)
Net expenses (c)	0.05%	0.02%(d)
Net investment income (loss)	4.06%	4.70%(d)
Portfolio turnover rate	20%	86%(e)

*	For the period March 30, 2020 (commencement of investment operations) through December 31, 2020. (See Note 1)
(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Does not include expenses of the Underlying Funds in which the Fund invests.
(d)	Annualized.
(e)	Not annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TARGET RETIREMENT FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class I
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$11.99	$11.05	$10.02	$10.73	$10.12
Income (loss) from investment operations:
Net investment income (loss) (a)	0.17	0.38	0.29	0.28	0.19
Net realized and unrealized gain (loss)	0.65	0.75	1.11	(0.55)	0.71
Total from investment operations	0.82	1.13	1.40	(0.27)	0.90
Distributions to shareholders from:
Net investment income	(0.28)	(0.18)	(0.31)	(0.29)	(0.20)
Net realized gains	(0.52)	(0.01)	(0.06)	(0.15)	(0.09)
Total distributions	(0.80)	(0.19)	(0.37)	(0.44)	(0.29)
Net asset value, end of period	$12.01	$11.99	$11.05	$10.02	$10.73
Total return (b)	6.87%	10.25%	13.98%	(2.50)%(c)	8.92%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$906	$21,801	$78	$108	$139
Ratios to Average Net Assets:
Total expenses (d)	0.42%	0.24%	0.24%	0.25%	0.36%
Net expenses (d)	0.24%	0.02%	(0.03)%(e)	(0.03)%(e)	(0.05)%(e)
Net investment income (loss)	1.36%	3.26%	2.64%	2.62%	1.78%
Portfolio turnover rate	33%	24%	26%	53%	25%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (2.50)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.
(e)	Due to the Fund waiving acquired Fund fees, the waiver exceeded total fund expenses.

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STATE STREET TARGET RETIREMENT FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$11.97	$11.03	$10.00	$10.71	$10.12
Income (loss) from investment operations:
Net investment income (loss) (a)	0.30	0.26	0.32	0.29	0.28
Net realized and unrealized gain (loss)	0.64	0.87	1.08	(0.56)	0.60
Total from investment operations	0.94	1.13	1.40	(0.27)	0.88
Distributions to shareholders from:
Net investment income	(0.31)	(0.18)	(0.31)	(0.29)	(0.20)
Net realized gains	(0.52)	(0.01)	(0.06)	(0.15)	(0.09)
Total distributions	(0.83)	(0.19)	(0.37)	(0.44)	(0.29)
Net asset value, end of period	$12.08	$11.97	$11.03	$10.00	$10.71
Total return (b)	7.92%	10.29%	14.00%	(2.50)%(c)	8.83%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$635,314	$491,138	$219,066	$200,840	$135,420
Ratios to Average Net Assets:
Total expenses (d)	0.15%	0.19%	0.24%	0.24%	0.36%
Net expenses (d)	(0.03)%(e)	(0.03)%(e)	(0.03)%(e)	(0.04)%(e)	(0.02)%(e)
Net investment income (loss)	2.40%	2.29%	2.92%	2.69%	2.61%
Portfolio turnover rate	33%	24%	26%	53%	25%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If the Affiliates had not made a contribution during the period ended December 31, 2018, total return would have remained (2.50)%.
(d)	Does not include expenses of the Underlying Funds in which the Fund invests.
(e)	Due to the Fund waiving acquired Fund fees, the waiver exceeded total fund expenses.

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Appendix A – Underlying Funds

The following is a brief description of the investment objective and principal investment policies of certain of the Underlying Funds in which the Target Retirement Funds may invest. The Funds invest in the Underlying Funds in varying proportions.

You'll find more detailed information about each of these Underlying Fund's investment strategies and risks in its prospectus and SAI. Refer to www.ssga.com or contact your financial advisor for details.

State Street Equity 500 Index II Portfolio

The State Street Equity 500 Index II Portfolio seeks to provide investment results that, before expenses, correspond generally to the total return of the S&P 500^® Index. The Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. Instead, the Portfolio, using a “passive” or “indexing” investment approach, seeks to provide investment results that, before expenses, correspond generally to the total return of the S&P 500. The Portfolio generally intends to invest in all stocks comprising the S&P 500 in approximate proportion to their weightings in the Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Portfolio may purchase a sample of the stocks in the Index in proportions expected by the Portfolio's investment adviser, SSGA FM, to match generally the performance of the Index as a whole. In addition, from time to time stocks are added to or removed from the Index. The Portfolio may sell securities that are represented in the Index, or purchase securities that are not yet represented in the Index, in anticipation of their removal from or addition to the Index. Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in securities that the Adviser determines have economic characteristics that are comparable to the economic characteristics of securities that comprise the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Portfolio may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Portfolio may also enter into other derivatives transactions, including the use of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Portfolio may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

State Street Small/Mid Cap Equity Index Portfolio

The State Street Small/Mid Cap Equity Index Portfolio seeks to provide investment results that, before expenses, correspond generally to the total return of an index that tracks the performance of mid-to small- capitalization exchange traded U.S. equity securities. The Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. Instead, the Portfolio, using a “passive” or “indexing” investment approach, seeks to provide investment results that, before expenses, correspond generally to the total return of the Russell Small Cap Completeness Index. The Portfolio generally intends to invest in all stocks comprising the Russell Small Cap Completeness Index in approximate proportion to their weightings in the Russell Small Cap Completeness Index. However, under various circumstances, it may not be possible or practicable to purchase all stocks in those weightings. In those circumstances, the Portfolio may purchase a sample of the stocks in the Russell Small Cap Completeness Index in proportions expected by SSGA FM, the investment adviser to the Portfolio, to match generally the performance of the Russell Small Cap Completeness Index as a whole. In addition, from time to time stocks are added to or removed from the Russell Small Cap Completeness Index. The Portfolio may sell securities that are represented in the Russell Small Cap Completeness Index, or purchase securities that are not yet represented in the Russell Small Cap Completeness Index, in anticipation of their removal

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from or addition to the Russell Small Cap Completeness Index. Under normal market conditions, the Portfolio invests at least 80% of its net assets (plus borrowings, if any) in stocks in the Russell Small Cap Completeness Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Russell Small Cap Completeness Index may be counted toward satisfaction of this 80% policy. In addition, the Fund may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). The Portfolio may purchase or sell futures contracts on the Index, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Portfolio might do so, for example, in order to increase its investment exposure pending investment of cash in the stocks comprising the Index. Alternatively, the Portfolio might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options or swap transactions relating to the Index or any securities comprising the Index, in lieu of investing directly in the stocks making up the Index. The Portfolio may, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

State Street Global All Cap Equity ex-U.S. Index Portfolio

The State Street Global All Cap Equity ex-U.S. Index Portfolio (the “Portfolio”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of a broad-based index of world (ex-U.S.) equity markets over the long term. The Portfolio is an “index” fund that seeks to track, before fees and expenses, the total return performance of the MSCI ACWI ex USA Investable Market Index (the “MSCI ACWI ex USA IMI Index” or sometimes referred to in context as the “Index”) over the long term. As an “index” fund, the Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. In seeking to track the performance of the Index, the Portfolio employs a sampling strategy, which means that the Portfolio is not required to purchase all of the securities represented in the Index. Instead, the Portfolio may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Portfolio will be based on a number of factors, including asset size of the Portfolio. The Adviser generally expects the Portfolio to hold fewer than the total number of securities in the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Portfolio's investment objective. Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) providing exposure to securities comprising the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. In addition, the Portfolio may invest in equity securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). The Portfolio may also purchase or sell futures contracts, or options on those futures, in lieu of investing directly in the stocks making up the Index. The Portfolio might do so, for example, in order to increase its investment exposure pending investment of cash in stocks or other investments. Alternatively, the Portfolio might use futures or options on futures to reduce its investment exposure in situations where it intends to sell a portion of the stocks in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options, forwards or swap transactions, in lieu of investing directly in the stocks making up the Index. The Portfolio may also, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

SPDR Dow Jones Global Real Estate ETF

The SPDR Dow Jones Global Real Estate ETF seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of an index based upon the global real estate market. In seeking to track the performance of the Dow Jones Global Select Real Estate Securities Index^sm, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA FM, the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in sub-

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stantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective. Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index and in depositary receipts ADRs or GDRs based on securities comprising the Index. In addition, in seeking to track the Index, the Fund may invest in equity securities that are not included in the Index (including common stock, preferred stock, depositary receipts and shares of other investment companies), cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). In seeking to track the Index, the Fund's assets will generally be concentrated in an industry or group of industries to the extent that the Index concentrates in a particular industry or group of industries.

SPDR Portfolio Long Term Treasury ETF

The SPDR Portfolio Long Term Treasury ETF seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the long term (10+ years) sector of the United States Treasury market. In seeking to track the performance of the Bloomberg Long U.S. Treasury Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA FM, the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective. Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index or in securities that the Adviser determines have economic characteristics that are substantially identical to the economic characteristics of the securities that comprise the Index. In addition, in seeking to track the Index, the Fund may invest in debt securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

State Street Aggregate Bond Index Portfolio

The State Street Aggregate Bond Index Portfolio seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the U.S. dollar denominated investment-grade bond market over the long term. The Portfolio is an “index” fund that seeks to track, before fees and expenses, the total return performance of the Bloomberg U.S. Aggregate Bond Index over the long term. As an “index” fund, the Portfolio is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment.

In seeking to track the performance of the Index, the Portfolio employs a sampling strategy, which means that the Portfolio will not typically purchase all of the securities represented in the Index. Instead, the Portfolio may purchase a subset of the securities in the Index, or securities the Adviser considers to be comparable to securities in the Index, in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Portfolio will be based on a number of factors, including asset size of the Portfolio. SSGA FM, the investment adviser to the Portfolio, generally expects the Portfolio to hold fewer than the total number of securities in the Index, but reserves the right to hold as many securities as it believes necessary to achieve the Portfolio's investment objective. Under normal circumstances, the Portfolio generally invests substantially all, but at least 80%, of its net assets (plus borrowings, if any) in securities comprising the Index or in securities that the Adviser determines have economic characteristics that are comparable to the economic characteristics of securities that comprise the Index. The notional value of the Portfolio's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in the Index may be counted toward satisfaction of this 80% policy. The Portfolio may also invest in other debt securities, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). The Portfolio may at times purchase or sell futures contracts on fixed-income securities, or options on those futures, in lieu of investing directly in fixed-income securities themselves. The Portfolio may also purchase or sell futures contracts and related options on the Index (or other fixed-income securities indices). The Portfolio might do so, for example, in order to adjust the interest-rate sensitivity of the Portfolio to bring the characteristics of the Portfolio more closely in line with those of the Index. It might also do so to increase its investment exposure pending investment of cash in bonds or other investments or to reduce its

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investment exposure in situations where it intends to sell a portion of the securities in its portfolio but the sale has not yet been completed. The Portfolio may also enter into other derivatives transactions, including the use of options or swap transactions, in lieu of investing directly in the stocks making up the Index. The Portfolio may, to the extent permitted by applicable law, invest in shares of other mutual funds whose investment objectives and policies are similar to those of the Portfolio (including funds advised by the Adviser).

SPDR Bloomberg High Yield Bond ETF

The SPDR Bloomberg High Yield Bond ETF seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the U.S. high yield corporate bond market. In seeking to track the performance of the Bloomberg High Yield Very Liquid Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA FM, the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective. Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index or in securities that the Adviser determines have economic characteristics that are substantially identical to the economic characteristics of the securities that comprise the Index. In addition, in seeking to track the Index, the Fund may invest in debt securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). In seeking to track the Index, the Fund's assets will generally be concentrated in an industry or group of industries to the extent that the Index concentrates in a particular industry or group of industries. The Fund may use derivatives, including credit default swaps and credit default index swaps, to obtain investment exposure that the Adviser expects to correlate closely with the Index, or a portion of the Index, and in managing cash flows.

SPDR Portfolio Short Term Treasury ETF

The SPDR Portfolio Short Term Treasury ETF seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the short term sector of the United States Treasury market. In seeking to track the performance of the Bloomberg 1-3 Year U.S. Treasury Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA FM, the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective. Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index or in securities that the Adviser determines have economic characteristics that are substantially identical to the economic characteristics of the securities that comprise the Index. In addition, in seeking to track the Index, the Fund may invest in debt securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

SPDR Portfolio Short Term Corporate Bond ETF

The SPDR Portfolio Short Term Corporate Bond ETF seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the short-term U.S. corporate bond market. In seeking to track the performance of the Bloomberg U.S. 1-3 Year Corporate Bond Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA FM, the investment

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adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective.

Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index or in securities that the Adviser determines have economic characteristics that are substantially identical to the economic characteristics of the securities that comprise the Index. In addition, in seeking to track the Index, the Fund may invest in debt securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). In seeking to track the Index, the Fund's assets will generally be concentrated in an industry or group of industries to the extent that the Index concentrates in a particular industry or group of industries. The Fund may use derivatives, including credit default swaps and credit default index swaps, to obtain investment exposure that the Adviser expects to correlate closely with the Index, or a portion of the Index, and in managing cash flows.

SPDR Bloomberg 1-10 Year TIPS ETF

The SPDR Bloomberg 1-10 Year TIPS ETF seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the 1-10 year inflation protected sector of the United States Treasury market. In seeking to track the performance of the Bloomberg 1-10 Year U.S. Government Inflation-Linked Bond Index, the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA FM, the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective.

SPDR Portfolio Intermediate Term Treasury ETF

The SPDR Portfolio Intermediate Term Treasury ETF seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the intermediate term (3-10 years) sector of the United States Treasury market. In seeking to track the performance of the Bloomberg 3-10 Year U.S. Treasury Index (the “Index”), the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors SSGA FM, the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective.

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Index/Trademark Licenses/Disclaimers

The Russell Small Cap Completeness^® Index is not sponsored, endorsed, sold or marketed by Frank Russell Company (“Russell”). The Russell Small Cap Completeness^® Index in no way suggests or implies an opinion by Russell as to the advisability of investment in any or all of the securities upon which the Russell Small Cap Completeness Index is based. Russell licenses to the Adviser certain trademarks and trade names of Russell and of the Russell Small Cap Completeness Index which are determined, composed and calculated by Russell without regard to the SPDR Russell Small Cap Completeness ETF. Russell is not responsible for and has not reviewed the Products nor any associated literature or publications and Russell makes no representation or warranty express or implied as to their accuracy or completeness, or otherwise. Russell reserves the right, at any time and without notice, to alter, amend, terminate or in any way change the Russell Small Cap Completeness Index. Russell has no obligation or liability in connection with the administration, marketing or trading of the Products.

S&P INDICES: The S& P 500 Index and the Dow Jones Global Select Real Estate Securities Index (the “Indices”) are products of S&P Dow Jones Indices LLC, (“SPDJI”), a division of S&P Global or its affiliates, and have been licensed for use by the Adviser. “S&P”, “Standard & Poor's” are registered trademarks of Standard & Poor's Financial Services LLC (“S&P'), a division of S&P Global; "Global Dow” is a registered trademark of Dow Jones Trademark Holdings LLC (“Dow Jones”); and these marks, together with the names of the S&P Indices, have been licensed for use by SPDJI and sub-licensed for use by the Adviser.

The State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF are not sponsored, endorsed, sold or marketed by SPDJI, Dow Jones, S&P, any of their respective affiliates (collectively, “S&P Dow Jones Indices”). S&P Dow Jones Indices does not make any representation or warranty, express or implied, to the owners of the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF or any member of the public regarding the advisability of investing in securities generally or in the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF particularly or the ability of the Index to track general market performance. S&P Dow Jones Indices licenses to Licensee the Index and certain trademarks, service marks and/or trade names of S&P Dow Jones Indices and/or its licensors. The Index is determined, composed and calculated by S&P Dow Jones Indices without regard to Licensee or the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF. S&P Dow Jones Indices has no obligation to take the needs of Licensee or the owners of the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF into consideration in determining, composing or calculating the Index. S&P Dow Jones Indices is not responsible for and has not participated in the determination of the prices, and amount of the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF or the timing of the issuance or sale of the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF or in the determination or calculation of the equation by which the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF is to be converted into cash, surrendered or redeemed, as the case may be. S&P Dow Jones Indices has no obligation or liability in connection with the administration, market-

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ing or trading of the State Street Equity 500 Index II Portfolio and the SPDR Dow Jones Global Real Estate ETF. S&P Dow Jones Indices LLC is not an investment or tax advisor. Inclusion of a security within an index is not a recommendation by S&P Dow Jones Indices to buy, sell, or hold such security, nor is it considered to be investment advice.

NEITHER S&P DOW JONES INDICES NOR THIRD PARTY LICENSOR GUARANTEES THE ADEQUACY, ACCURACY, TIMELINESS AND/OR THE COMPLETENESS OF THE INDEX OR ANY DATA RELATED THERETO OR ANY COMMUNICATION, INCLUDING BUT NOT LIMITED TO, ORAL OR WRITTEN COMMUNICATION (INCLUDING ELECTRONIC COMMUNICATIONS) WITH RESPECT THERETO. S&P DOW JONES INDICES AND THIRD PARTY LICENSOR SHALL NOT BE SUBJECT TO ANY DAMAGES OR LIABILITY FOR ANY ERRORS, OMISSIONS, OR DELAYS THEREIN. S&P DOW JONES INDICES AND THIRD PARTY LICENSOR MAKES NO EXPRESS OR IMPLIED WARRANTIES, AND EXPRESSLY DISCLAIMS ALL WARRANTIES, OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE OR AS TO RESULTS TO BE OBTAINED BY LICENSEE, OWNERS OF THE STATE STREET EQUITY 500 INDEX II PORTFOLIO AND THE SPDR DOW JONES GLOBAL REAL ESTATE ETF, OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE INDICES OR WITH RESPECT TO ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT WHATSOEVER SHALL S&P DOW JONES INDEX OR THIRD PARTY LICENSOR BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES INCLUDING BUT NOT LIMITED TO, LOSS OF PROFITS, TRADING LOSSES, LOST TIME OR GOODWILL, EVEN IF THEY HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, WHETHER IN CONTRACT, TORT, STRICT LIABILITY, OR OTHERWISE. THERE ARE NO THIRD PARTY BENEFICIARIES OF ANY AGREEMENTS OR ARRANGEMENTS BETWEEN S&P DOW JONES INDICES AND LICENSEE, OTHER THAN THE LICENSORS OF S&P DOW JONES INDICES.

“ Bloomberg^®” and the Bloomberg 1-3 Year U.S. Treasury Index, Bloomberg 3-10 Year U.S. Treasury Index, Bloomberg 1-10 Year U.S. Government Inflation-Linked Bond Index, Bloomberg LongU.S. Treasury Index, Bloomberg U.S. 1-3 Year Corporate Bond Index, Bloomberg U.S. Aggregate Bond Index, Bloomberg High Yield Very Liquid Index, (collectively, the “Bloomberg Indices”) are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited (“BISL”), the administrator of the Bloomberg Indices (collectively, “Bloomberg”), and have been licensed for use for certain purposes by the Licensee.The SPDR Bloomberg 1-10 Year TIPS ETF and SPDR Bloomberg High Yield Bond ETF, along with other products advised by an affiliate of the Licensee (collectively, the “Products”) are not sponsored, endorsed, sold or marketed by Bloomberg. Bloomberg does not make any representation or warranty, express or implied, to the owners of or counterparties to the Products or any member of the public regarding the advisability of investing in securities generally or in the Products particularly. The only relationship of Bloomberg to the Licensee in respect of the Bloomberg Indices is the licensing of certain trademarks, trade names and service marks and of the Bloomberg Indices, which are determined, composed and calculated by BISL without regard to the Licensee or the Products. Bloomberg has no obligation to take the needs of the Licensee or the owners of the Products into consideration in determining, composing or calculating the Bloomberg Indices. Bloomberg is not responsible for and has not participated in the determination of the timing, price, or quantities of the Products to be issued. Bloomberg shall not have any obligation or liability, including, without limitation, to the Products' customers, in connection with the administration, marketing or trading of the Products.BLOOMBERG DOES NOT GUARANTEE THE ACCURACY AND/OR THE COMPLETENESS OF THE BLOOMBERG INDICES OR ANY DATA RELATED THERETO AND SHALL HAVE NO LIABILITY FOR ANY ERRORS, OMISSIONS OR INTERRUPTIONS THEREIN. BLOOMBERG DOES NOT MAKE ANY WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY THE LICENSEE, OWNERS OF THE PRODUCTS OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE BLOOMBERG INDICES OR ANY DATA RELATED THERETO. BLOOMBERG DOES NOT MAKE ANY EXPRESS OR IMPLIED WARRANTIES AND EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE BLOOMBERG INDICES OR ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, TO THE MAXIMUM EXTENT ALLOWED BY LAW, BLOOMBERG, ITS LICENSORS, AND ITS AND THEIR RESPECTIVE EMPLOYEES, CONTRACTORS, AGENTS, SUPPLIERS, AND VENDORS SHALL HAVE NO LIABILITY OR RESPONSIBILITY WHATSOEVER FOR ANY INJURY OR DAMAGES—WHETHER DIRECT, INDIRECT, CONSEQUENTIAL, INCIDENTAL, PUNITIVE OR OTHERWISE—ARISING IN CONNECTION WITH THE PRODUCTS OR BLOOMBERG INDICES OR ANY DATA OR VALUES RELATING THERETO—WHETHER ARISING FROM THEIR NEGLIGENCE OR OTHERWISE, EVEN IF NOTIFIED OF THE POSSIBILITY THEREOF.

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ARE SERVICE MARK(S) OF MSCI OR ITS AFFILIATES AND HAVE BEEN LICENSED FOR USE FOR CERTAIN PURPOSES BY THE LICENSEE. NONE OF THE MSCI PARTIES MAKES ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY REGARDING THE ADVISABILITY OF INVESTING IN FUNDS GENERALLY OR IN THE MSCI FUNDS PARTICULARLY OR THE ABILITY OF ANY MSCI INDEX TO TRACK CORRESPONDING STOCK MARKET PERFORMANCE. MSCI OR ITS AFFILIATES ARE THE LICENSORS OF CERTAIN TRADEMARKS, SERVICE MARKS AND TRADE NAMES AND OF THE MSCI INDICES WHICH ARE DETERMINED, COMPOSED AND CALCULATED BY MSCI WITHOUT REGARD TO THE MSCI FUNDS OR THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY. NONE OF THE MSCI PARTIES HAS ANY OBLIGATION TO TAKE THE NEEDS OF THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY INTO CONSIDERATION IN DETERMINING, COMPOSING OR CALCULATING THE MSCI INDICES. NONE OF THE MSCI PARTIES IS RESPONSIBLE FOR OR HAS PARTICIPATED IN THE DETERMINATION OF THE TIMING OF, PRICES AT, OR QUANTITIES OF THE MSCI FUNDS TO BE ISSUED OR IN THE DETERMINATION OR CALCULATION OF THE EQUATION BY OR THE CONSIDERATION INTO WHICH THE MSCI FUNDS ARE REDEEMABLE. FURTHER, NONE OF THE MSCI PARTIES HAS ANY OBLIGATION OR LIABILITY TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY IN CONNECTION WITH THE ADMINISTRATION, MARKETING OR OFFERING OF THE MSCI FUNDS.

SPDR Trademark. The “SPDR” trademark is used under license from Standard & Poor's Financial Services LLC (“S&P”). No Fund offered by the Trust or its affiliates is sponsored, endorsed, sold or marketed by S&P or its affiliates. S&P makes no representation or warranty, express or implied, to the owners of any Fund or any member of the public regarding the advisability of investing in securities generally or in the Funds particularly or the ability of the Index on which the Fund is based to track general stock market performance. S&P is not responsible for and has not participated in any determination or calculation made with respect to issuance or redemption of Fund Shares. S&P has no obligation or liability in connection with the administration, marketing or trading of the Funds.

WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT SHALL S&P HAVE ANY LIABILITY FOR ANY SPECIAL, PUNITIVE, INDIRECT, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, LOST PROFITS), EVEN IF NOTIFIED OF THE POSSIBILITY OF SUCH DAMAGES.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Funds:

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITTDSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Institutional U.S. Government Money Market Fund: Class G (SSOXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the Fund offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund offers multiple classes of shares. This Prospectus covers only the Class G Shares.

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Fund Summary	1
State Street Institutional U.S. Government Money Market Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	7
Additional Information About Non-Principal Investment Strategies and Risks	13
Portfolio Holdings Disclosure	14
Management and Organization	15
Shareholder Information	17
Dividends, Distributions and Tax Considerations	22
Financial Intermediary Arrangements	23
Financial Highlights	25

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.03%
Total Annual Fund Operating Expenses¹	0.08%

Example:

1 year		3 years		5 years		10 years
$8		$26		$45		$103

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Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Class G shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.59% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q2, 2015)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Since Inception		Inception Date
Class G		0.03%		1.05%		0.77%		10/6/2014

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Class G
To establish an account	$1,000,000,000
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

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Tax Information

The Fund's distributions are expected to be taxed as ordinary income unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or individual retirement account. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

Investment Objective

The investment objective of the U.S. Government Fund, as stated in the Fund Summary, may be changed without shareholder approval.

U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

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It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by the Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when the Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

The credit rating assigned to any particular investment does not necessarily reflect the issuer's current financial condition and does not reflect an assessment of an investment's volatility or liquidity. Securities rated in the lowest category of investment-grade are considered to have speculative characteristics. If a security held by the Fund loses its rating or its rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

Debt Securities Risk. The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

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to sell its more liquid portfolio investments to meet a large redemption, in which case the Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. The Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Market Disruption and Geopolitical Risk. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of the Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of the Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by the Fund. To the extent the Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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be greatly reduced for periods of time. Some interest rates have been very low and in some cases yields are negative. Governments and central banks, including the Federal Reserve in the United States, have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. The impact of these measures, and whether they will be effective to mitigate the economic and market disruption, will not be known for some time. The foregoing could result in disruptions to the services provided to the Fund by its service providers.

Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Money Market Risk. An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Although a money market fund generally seeks to preserve the value of its shares at $1.00 per share, there can be no assurance that it will do so, and it is possible to lose money by investing in a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause a money market fund's share price to fall below $1.00. It is possible that a money market fund will issue and redeem shares at $1.00 per share at times when the fair value of the money market fund's portfolio per share is more or less than $1.00. A money market fund may be permitted or required to impose redemption fees or to impose limitations on redemptions during periods of high illiquidity in

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the markets for the investments held by it. None of State Street Corporation, State Street, State Street Global Advisors, SSGA FM or their affiliates (collectively, the “State Street Entities”) guarantee the value of an investment in a money market fund at $1.00 per share. Investors should have no expectation of capital support to a money market fund from the State Street Entities.

Mortgage-Related and Other Asset-Backed Securities Risk. Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically structured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in the Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which the Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Rapid Changes in Interest Rates. The values of instruments held by the Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause the Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses could impair the Fund's ability to maintain a stable share price of $1.00.

Significant Exposure to U.S. Government Agencies or Instrumentalities Risk. To the extent the Fund focuses its investments in securities issued or guaranteed by U.S. government agencies or instrumentalities, any market movements, regulatory changes or changes in political or economic conditions that affect the U.S. government agencies or instru-

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mentalities in which the Fund invests may have a significant impact on the Fund's performance. Events that would adversely affect the market prices of securities issued or guaranteed by one government agency or instrumentality may adversely affect the market price of securities issued or guaranteed by other government agencies or instrumentalities.

Stable Share Price Risk. If the market value of one or more of the Fund's investments changes substantially, the Fund may not be able to maintain a stable share price of $1.00. This risk typically is higher during periods of rapidly changing interest rates or when issuer credit quality generally is falling, and is made worse when the Fund experiences significant redemption requests.

U.S. Treasury Obligations Risk. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund's U.S. Treasury obligations to decline. The total public debt of the United States as a percent of gross domestic product grew rapidly after the financial crisis of 2008 and has remained at a historically high level. Although high debt levels do not necessarily indicate or cause economic problems, they may create certain systemic risks if sound debt management practices are not implemented. A high national debt level may increase market pressures to meet government funding needs, which may drive debt cost higher and cause a country to sell additional debt, thereby increasing refinancing risk. A high national debt also raises concerns that a government will not be able to make principal or interest payments when they are due. In the worst case, unsustainable debt levels can cause a decline in the value of the dollar (which may lead to inflation), and can prevent the U.S. government from implementing effective counter-cyclical fiscal policy in economic downturns. On August 5, 2011, Standard & Poor's Ratings Services downgraded U.S. Treasury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

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the changes in market rates or may have limits on the maximum increases in coupon rates. Alternatively, during periods of declining interest rates, the coupon rates on such securities will typically readjust downward resulting in a lower yield. The Fund may also invest in variable or floating rate equity securities, whose dividend payments vary based on changes in market rates of interest or other factors.

Additional Information About Non-Principal Investment Strategies and Risks

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and

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systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

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A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.01% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

Additional Information

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Shareholder Information

Determination of Net Asset Value

The Fund determines its NAV per share once each day on which the New York Stock Exchange (the “NYSE”), the Federal Reserve banks and State Street are open for business (a “Business Day”) at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event the Fund will determine its NAV at the earlier closing time (the time when the Fund determines its NAV per share is referred to herein as the “Valuation Time”). Pricing does not occur on NYSE holidays.

The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. The Fund reserves the right to accept orders to purchase or redeem shares, or to continue to accept such orders following the close of the NYSE, on any day that is not a Business Day or any day on which the NYSE closes early, provided the Federal Reserve remains open. Consequently, the NAV of the Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's Shares. The Fund also may establish special hours on those days to determine the Fund's NAV. In the event that the Fund invokes the right to accept orders to purchase or redeem shares on any day that is not a Business Day or adopt special hours of operation, the Fund will post advance notice of these events at: www.ssga.com/cash.

The Fund seeks to maintain a $1.00 per share NAV and, accordingly, uses the amortized cost valuation method, in compliance with the risk limiting conditions of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”), to value its portfolio instruments. The amortized cost valuation method initially prices an instrument at its cost and thereafter assumes a constant amortization to maturity of any discount or premium, regardless of the impact of fluctuating interest rates on the market value of the instrument.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

The Fund offers one class of shares through this Prospectus: Class G shares, available to you subject to the eligibility requirements set forth below. All classes of the Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. You should choose the class with the expense structure that best meets your needs for which you are eligible. In choosing a share class, you should consider the amount you plan to invest. Your investment professional can help you choose the share class that best suits your investment needs.

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The chart below summarizes the features of the share class. This chart is only a general summary, and you should read the description of the Fund's expenses in the Fund Summary in this Prospectus.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their family. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

Minimum Initial Investment	$1,000,000,000
Maximum Investment	None.
Initial Sales Charge	No. Entire purchase price is invested in shares of the Fund.
Deferred (CDSC) Sales Charge	No.
Distribution and/or Service (12b-1) Fees	No.
Redemption Fees	No.

Investors pay no sales load to invest in Class G shares of the Fund. The price for Fund Shares is the NAV per share. Purchase requests received by the Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Times will earn dividend accrual for that purchase. All purchases that are made by check will be priced with the last valuation price and begin earning dividends the following Business Day after the day the order is accepted. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) All purchase orders are subject to acceptance by the Fund. The Fund intends to be as fully invested as is practicable; therefore, investments must be made in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank).

The minimum initial investment in Class G shares of the Fund is $1 billion although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include, but are not limited to, accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Fund and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below). The Fund requires prior notification of subsequent investments in excess of $50 million. The Fund reserves the right to cease accepting investments at any time or to reject any investment order. In addition, the Fund may limit the amount of a purchase order received after 3:00 p.m. ET.

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How to Purchase Shares

By Mail:

An initial investment in the Fund must be preceded or accompanied by a completed, signed Institutional Account Application Form, sent to:
State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Fund and the Fund's agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

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redemption order is placed after 5:00 p.m. ET, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent), but no later than the following Business Day. The Fund may postpone and/or suspend redemption and payment beyond the foregoing time periods only as follows:

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;
c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

A request for a partial redemption by an investor whose account balance is below a minimum amount or a request for partial redemption by an investor that would bring the account below a minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Fund reserves the right to modify minimum account requirements at any time with or without prior notice. The Fund also reserves the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

The Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. Although the Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Fund will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Fund calculates its NAV earlier than normal, the Fund reserves the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

About Telephone Transactions. Telephone transactions are convenient but are not free from risk. Neither the Fund nor the Fund's agents will be responsible for any losses resulting from unauthorized telephone transactions if reasonable security procedures are followed. In addition, you are responsible for: (i) verifying the accuracy of all data and information transmitted by telephone, (ii) verifying the accuracy of your account statements immediately upon receipt, and (iii) promptly notifying the Fund of any errors or inaccuracies, including, without limitation, any errors or inaccuracies relating to shareholder data or information transmitted by telephone. During periods of heavy market activity or other times, it may be difficult to reach the Fund by telephone. If you are unable to reach us by telephone, consider sending written instructions.

The Fund may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and the Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Fund's Prospectus and the annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

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The Fund invests substantially all of its investible assets in a Portfolio that is treated as a partnership for U.S. federal income tax purposes. Therefore, the nature and character of the Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and the Fund will be allocated its share of the Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of the Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of the Fund will be to the Fund's allocable share of the assets of the Portfolio.

For U.S. federal income tax purposes, distributions of investment income are generally taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Portfolio or Fund owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. The Fund generally does not expect to make distributions that are eligible for taxation as long-term capital gains. Any net short-term gains the Fund distributes will be taxable to you as ordinary income. Distributions are taxable to you even if they are paid from income or gains earned by the Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

If the NAV of Fund Shares were to vary from $1.0000 per share, shareholders generally would realize a gain or loss upon the redemption or other taxable disposition of such Fund Shares. Any such gains generally would be taxable to you as either short-term or long-term capital gain, depending upon how long you have held such Fund Shares.

The Internal Revenue Service (the “IRS”) has issued final regulations and published guidance that permit a simplified method of accounting for gains and losses realized upon the disposition of money market fund shares. Shareholders should see the SAI for further information.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund and net gains recognized on the redemption of Fund Shares.

The U.S. Treasury and IRS generally require the Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Code, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Financial Intermediary Arrangements

Payments to Financial Intermediaries

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The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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Financial Highlights

The financial highlight tables are intended to help you understand the Fund's Class G Shares financial performance for the past five fiscal years. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class G (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0043	0.0215	0.0180	0.0082
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—	0.0001
Total from investment operations	0.0001	0.0043	0.0215	0.0180	0.0083
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0043)	(0.0215)	(0.0180)	(0.0083)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0043)	(0.0215)	(0.0180)	(0.0083)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.03%	0.43%	2.17%	1.80%	0.83%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$7,180,149	$6,025,209	$3,607,164	$3,065,834	$4,349,842
Ratios to Average Net Assets:
Total expenses	0.08%	0.08%	0.08%	0.08%	0.08%
Net expenses	0.05%	0.08%	0.08%	0.08%	0.08%
Net investment income (loss)	0.03%	0.37%	2.12%	1.74%	0.95%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Fund's website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITCLGSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Hedged International Developed Equity Index Fund

Class A (SSHEX) Class I (SSHNX) Class K (SSHQX)

State Street International Developed Equity Index Fund

Class A (SSIHX) Class I (SSIKX) Class K (SSIWX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Class A, Class I and Class K Shares of the applicable Funds.

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Fund Summaries	1
State Street Hedged International Developed Equity Index Fund	1
State Street International Developed Equity Index Fund	10
Additional Information About Investment Objectives, Principal Strategies and Risks	18
Additional Information About Non-Principal Investment Strategies and Risks	30
Portfolio Holdings Disclosure	31
Management and Organization	32
Shareholder Information	34
Dividends, Distributions and Tax Considerations	47
Financial Intermediary Arrangements	50
Financial Highlights	52
Index/Trademark Licenses/Disclaimers	54

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State Street Hedged International Developed Equity Index Fund

Investment Objective

The State Street Hedged International Developed Equity Index Fund (the “Hedged International Developed Equity Index Fund” or sometimes referred to in context as the “Fund”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of a broad-based developed market (ex-U.S. and Canada) large and mid capitalization equity index, hedged to the U.S. dollar, over the long term.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 7% of the Fund's Prospectus.

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee²	0.14%	0.14%	0.14%
Distribution and/or Shareholder Service (12b-1) Fees	0.25%	0.00%	0.00%
Other Expenses³	0.41%	0.41%	0.21%
Total Annual Fund Operating Expenses	0.80%	0.55%	0.35%
Less Fee Waivers and/or Expense Reimbursements⁴	(0.15%)	(0.15%)	(0.15%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.65%	0.40%	0.20%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023 to waive the portion of the Fund's management fee attributable to the Fund's assets invested in State Street International Developed Equity Index Portfolio, a separate series of State Street Master Funds (the “Portfolio”). This arrangement may not be terminated prior to April 30, 2023 except with the approval of the Fund's Board of Trustees.

³	Other Expenses are based on estimates for the current fiscal year for Class A and Class I shares.

⁴

The Adviser is contractually obligated until April 30, 2023 (i) to waive up to the full amount of the advisory fee payable by the Fund and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees other than the fees of the Portfolio, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.15% of average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees.

Example:

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year and that the Fund's operating expenses remain the same. The calculation of costs for the one-year period takes into account the effect of any current contractual fee waivers and/or reimbursements; and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 year	3 years	5 years	10 years
Class A	$588	$753	$932	$1,450
Class I	$41	$161	$292	$675
Class K	$20	$97	$181	$428

Portfolio Turnover:

Principal Investment Strategies

The Fund is an “index” fund that seeks to track, before fees and expenses, the total return of the MSCI EAFE (Europe, Australasia, Far East) 100% Hedged to USD Index (the “Index”) over the long term. As an “index” fund, the Fund is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment. The return of the Index is affected by the performance of Index constituents and the hedging strategy. In general, the Index would have higher returns than an equivalent unhedged index when the component currencies are weakening relative to the U.S. dollar. Conversely, the Index generally would have lower returns than an equivalent unhedged index when the component currencies are rising relative to the U.S. dollar.

In seeking to track the performance of the Index, the Fund expects to employ a sampling strategy, which means that the Fund will not typically purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index or other investments in an effort to create a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Fund will be based on a number of factors, including the asset size of the Fund. Based on its analysis of these factors, SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, may, instead, invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index.

Under normal circumstances, the Fund invests substantially all, but as a matter of policy no less than 80%, of its net assets (plus borrowings, if any) in securities, or American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) based on securities, comprising the Index, or in other funds, including funds sponsored by the Adviser or its affiliates, in currency hedging instruments (and related collateral, if any), or in other investments, that the Adviser expects to provide a return highly correlated to the Index or a portion of the Index. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposure comparable, in the judgment of the Adviser, to the foregoing types of investments may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in its policy to invest at least 80% of its assets as described in the foregoing. The Fund may invest in equity securities that are not included in the Index (including common stock, preferred stock, depositary receipts and shares of other investment companies), currency transactions, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). The Fund may use derivatives, including futures contracts and options, swaps, and contracts for differences, to obtain investment exposures that the Adviser expects to correlate closely with the Index or a portion of the Index.

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ments that provide exposures comparable, in the judgment of the Adviser, to investments in equity securities of issuers in developing economies or securities markets may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least 60 days' notice prior to any change in this 80% investment policy.

The Fund currently intends to gain all of its investment exposure to, and track the performance of, the Index constituents by investing in the State Street International Developed Equity Index Portfolio (the “Portfolio”) and employ its currency hedging strategy by directly entering into currency hedging transactions. The Adviser also serves as investment adviser to the Portfolio. When the Fund invests in the Portfolio, the Fund participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” with respect to the Index constituents also generally describe the expected investment activities of the Portfolio.

The Fund intends to hedge its non-U.S. currency exposure to the U.S. dollar, in a manner intended to replicate the currency hedge reflected in the Index. For this purpose, the Fund may enter into foreign currency forward contracts, forward currency futures and options, and currency swaps. The Index hedges each foreign currency in the Index back to the U.S. dollar by selling foreign currency forwards at the one-month forward rate. The size and exchange rate of each currency hedge is reset by the Index one time per month. Even if the Fund's hedging strategy works as intended, changes in currency exchange rates will still affect Fund returns (see “Currency Hedging Risk” below). The Fund's performance, like that of the Index, will depend on both the performance of the stocks comprising the Fund and the performance of the U.S. dollar relative to foreign currencies.

The Index is designed to capture the performance that can be achieved by hedging the currency exposures of its parent index, the MSCI EAFE Index, to the U.S. dollar. The MSCI EAFE Index is a free float-adjusted market capitalization index that is designed to capture large and mid-cap securities in developed market countries, excluding the United States and Canada. As of February 28, 2022, the MSCI EAFE Index comprised 822 securities covering companies across 21 countries and represented 84.74% of the free float-adjusted market capitalization of those countries. As of February 28, 2022, a significant portion of the MSCI EAFE Index comprised companies in the financial sector, and companies located in Japan, the United Kingdom and Europe and a significant portion of the Index constituents are denominated in the Yen, the Pound Sterling and the Euro, although this may change from time to time. As of February 28, 2022, the full market capitalization of the companies included in the MSCI EAFE Index ranged from $1.24 billion to $367.52 billion. As of February 28, 2022, countries covered in the MSCI EAFE Index included Australia, Austria, Belgium, Denmark, Finland, France, Germany, Hong Kong, Ireland, Israel, Italy, Japan, the Netherlands, New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland and the United Kingdom, although this may change from time to time.

The Index is sponsored by MSCI, Inc. (the “Index Provider”) which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks

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the value of the yen. Japanese intervention in the currency markets could cause the value of the yen to fluctuate sharply and unpredictably and could cause losses to investors. Japan has an aging workforce and has experienced a significant population decline in recent years. Japan's labor market appears to be undergoing fundamental structural changes, as a labor market traditionally accustomed to lifetime employment adjusts to meet the need for increased labor mobility, which may adversely affect Japan's economic competitiveness. Natural disasters, such as earthquakes, volcanoes, typhoons or tsunamis, could occur in Japan or surrounding areas and could negatively affect the Japanese economy and, in turn, the Fund.

Currency Hedging Risk: When a derivative is used as a hedge against a position that the Fund holds, any gain generated by the derivative generally should be substantially offset by losses on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between a derivative and its reference asset. For example, because the Fund's currency hedge is reset on a monthly basis, based on the size of the Fund's exposure to a currency at a certain point in time, the size of each currency hedge could be greater or less than the Fund's total exposure in that currency intra-month and currency risk may develop or increase between resets. Furthermore, while the Fund is designed to hedge against currency fluctuations, it is possible that a degree of currency exposure may remain even at the time a hedging transaction is implemented. As a result, changes in currency exchange rates may affect Fund returns even when the hedge works as intended. The effectiveness of the Fund's currency hedging strategy will also generally be affected by both the volatility of the securities included in the Index, and the volatility of the U.S. dollar relative to the currencies to be hedged. Increased volatility may reduce the effectiveness of the Fund's currency hedging strategy and may impact the costs associated with hedging transactions. The effectiveness of the Fund's currency hedging strategy and the costs associated with hedging transactions may also in general be affected by interest rates. Significant differences between U.S. dollar interest rates and foreign currency interest rates may further impact the effectiveness of the Fund's currency hedging strategy. There can be no assurance that the Fund's hedging transactions will be effective. The Fund's currency hedging activities will potentially increase or accelerate distributions to shareholders, increase distributions taxed to individuals as ordinary income, result in the re-characterization of prior ordinary income distributions as return of capital, or generate losses that cannot be used to offset income or capital gain in subsequent years. The Fund will bear the costs associated with any such hedging transaction, regardless of any gain or loss experienced on the hedging transaction.

Currency Risk: Despite the Fund's currency hedging strategy, the value of the Fund's assets may be affected favorably or unfavorably by currency exchange rates, currency exchange control regulations, and restrictions or prohibitions on the repatriation of foreign currencies. Foreign currency exchange rates may have significant volatility, and changes in the values of foreign currencies against the U.S. dollar may result in substantial declines in the values of the Fund's, or the Portfolio's, assets denominated in foreign currencies. Because the Fund's, or the Portfolio's, net asset values (“NAVs”) are determined in U.S. dollars, the Fund's NAV could decline if the currency of a non-U.S. market in which the Fund invests depreciates against the U.S. dollar and the Fund's attempt to hedge currency exposure is unsuccessful. Generally, an increase in the value of the U.S. dollar against a foreign currency will reduce the value of a security denominated in that foreign currency when measured in U.S. dollars, thereby decreasing the Fund's overall NAV. A foreign currency may be affected favorably or unfavorably by currency exchange rates, currency control regulations and restrictions or prohibitions on the repatriation of the foreign currency. Fluctuations in the exchange values of currencies could affect the economy or particular business operations of companies in a geographic region in which the Fund or the Portfolio invests, causing an adverse impact on the Fund's, or the Portfolio's, investments in the affected region and the United States. As a result, investors have the potential for losses regardless of the length of time they intend to hold Fund Shares.

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or other market conditions. Larger companies may not be able to maintain growth at the high rates that may be achieved by well-managed smaller and mid-sized companies.

Underlying Fund Risk: The Fund currently intends to gain all of its investment exposure to, and track the performance of, the index constituents by investing in another pooled investment vehicle (an “underlying fund”). The ability of the Fund to meet its investment objective with respect to the index constituents is directly related to the ability of the underlying fund to meet its investment objective. The Adviser serves as investment adviser to the underlying fund, leading to potential conflicts of interest. The Fund will bear its pro rata portion of the expenses incurred by the underlying fund. Substantial redemptions by other investors in an underlying fund may affect the underlying fund's investment program adversely and limit the ability of the underlying fund to achieve its objective.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Hedged International Developed Equity Index Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Class K shares' returns have varied for each full calendar year shown. Except for differences in returns resulting from differences in fees and expenses, all share classes would have substantially similar returns because all share classes invest in the same portfolio of securities. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Return (years ended 12/31)

Highest Quarterly Return: 14.53% (Q2, 2020)
Lowest Quarterly Return: -20.79% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

	One Year	Five Years	Since Inception	Inception Date
Class K				5/29/2015
Return Before Taxes	19.31%	10.10%	7.02%
Return After Taxes on Distributions	18.54%	9.06%	6.03%
Return After Taxes on Distributions and Sale of Fund Shares	12.05%	7.82%	5.33%
MSCI EAFE 100% Hedged to USD Index (reflects no deduction for fees, expenses or taxes other than withholding taxes on reinvested dividends)	19.43%	10.17%	7.32%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

The professionals primarily responsible for the day-to-day management of the Fund are Michael Feehily, Karl Schneider and David Chin, each of which has served as a portfolio manager of the Fund since inception in 2015.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

David Chin is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. He joined the Adviser in 1999.

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Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street International Developed Equity Index Fund

Investment Objective

The State Street International Developed Equity Index Fund (the “International Developed Equity Index Fund” or sometimes referred to in context as the “Fund”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of a broad-based developed market (ex-U.S. and Canada) large and mid-capitalization equity index over the long term.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 7% of the Fund's Prospectus. The expenses shown in the table and the Example reflect the expenses of both the Fund and the Fund's proportionate share of the expenses of the State Street International Developed Equity Index Portfolio (the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee²	0.11%	0.11%	0.11%
Distribution and/or Shareholder Service (12b-1) Fees	0.25%	0.00%	0.00%
Other Expenses³	0.95%	0.95%	0.75%
Total Annual Fund Operating Expenses	1.31%	1.06%	0.86%
Less Fee Waivers and/or Expense Reimbursements⁴	(0.72)%	(0.72)%	(0.72)%
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.59%	0.34%	0.14%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

³	Other Expenses are based on estimates for the current fiscal year.

⁴

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Example:

	1 year	3 years
Class A	$582	$851
Class I	$35	$265
Class K	$14	$202

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. The Fund's portfolio turnover rate has been omitted because the Fund had not commenced investment operations prior to the end of the most recent fiscal year.

Principal Investment Strategies

The Fund is an “index” fund that seeks to track, before fees and expenses, the total return of the MSCI EAFE (Europe, Australasia, Far East) Index (the “Index”) over the long term. As an “index” fund, the Fund is not managed according to traditional methods of “active” investment management, which involve the buying and selling of securities based upon economic, financial and market analysis and investment judgment.

Under normal circumstances, the Fund invests substantially all, but as a matter of policy no less than 80%, of its net assets (plus borrowings, if any) in securities, or American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) based on securities, comprising the Index, or in other funds, including funds sponsored by the Adviser or its affiliates, or in other investments, that the Adviser expects to provide a return highly correlated to the Index or a portion of the Index. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposure comparable, in the judgment of the Adviser, to the foregoing types of investments may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in its policy to invest at least 80% of its assets as described in the foregoing. The Fund may invest in equity securities that are not included in the Index (including common stock, preferred stock, depositary receipts and shares of other investment companies), cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). The Fund may use derivatives, including futures contracts and options, swaps, and contracts for differences, to obtain investment exposures that the Adviser expects to correlate closely with the Index or a portion of the Index.

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The Fund currently intends to invest nearly all of its assets in the Portfolio, another open-end investment company managed by the Adviser, with an investment objective and policies substantially identical to those of the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Portfolio and it participates in the investment returns achieved by the Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Portfolio.

The Index is a free float-adjusted market capitalization index that is designed to capture large and mid-cap securities in developed market countries, excluding the United States and Canada. As of February 28, 2022, the Index comprised 822 securities covering companies across 21 countries and represented 84.74% of the free float-adjusted market capitalization of those countries. As of February 28, 2022, a significant portion of the Index comprised companies in the financial sector and companies located in Japan, the United Kingdom and Europe and a significant portion of the Index constituents are denominated in the Yen, the Pound Sterling and the Euro, although this may change from time to time. As of February 28, 2022, the full market capitalization of the companies included in the Index ranged from $1.24 billion to $367.52 billion. As of February 28, 2022, countries covered in the Index included Australia, Austria, Belgium, Denmark, Finland, France, Germany, Hong Kong, Ireland, Israel, Italy, Japan, the Netherlands, New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland and the United Kingdom, although this may change from time to time.

Principal Risks

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experience a dramatic decline in value when such companies experience substantial declines in the valuations of their assets, take action to raise capital (such as the issuance of debt or equity securities), or cease operations. Credit losses resulting from financial difficulties of borrowers and financial losses associated with investment activities can negatively impact the sector. Insurance companies may be subject to severe price competition. Adverse economic, business or political developments could adversely affect financial institutions engaged in mortgage finance or other lending or investing activities directly or indirectly connected to the value of real estate.

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greater fluctuation in their valuations from one day to the next than if market quotations were used. In addition, there is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

Performance

Performance information for the Fund has been omitted because the Fund had not commenced investment operations as of the date of this Prospectus. Once the Fund has completed a full calendar year of operations, a bar chart and table will be included that will provide some indication of the risks of investing in the Fund by showing the variability of the Fund's returns based on net assets and comparing the Fund's performance to the Index. The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Portfolio.

The professionals primarily responsible for the day-to-day management of the Portfolio and the Fund are Michael Feehily, Karl Schneider and David Chin, each of which has served as a portfolio manager of the Fund since organization in 2015.

Michael Feehily, CFA, is a Senior Managing Director of the Adviser and the Head of Global Equity Beta Solutions in the Americas. He worked at the Adviser from 1997 to 2006 and rejoined in 2010.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Deputy Head of Global Equity Beta Solutions in the Americas. He joined the Adviser in 1997.

David Chin is a Vice President of the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. He joined the Adviser in 1999.

Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

State Street Hedged International Developed Equity Index Fund

Principal Investment Strategies

In seeking to track the performance of the Index, the Fund expects to employ a sampling strategy, which means that the Fund will not typically purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index or other investments in an effort to create a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Fund will be based on a number of factors, including the asset size of the Fund. Based on its analysis of these factors, SSGA FM may, instead, invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index.

Under normal circumstances, the Fund will invest at least 80% of its net assets (plus borrowings, if any) in equity securities of issuers in developed economies or securities markets. For this purpose, countries with “developed economies or securities markets” refers to countries that are included in the Index, or a global developed markets equity index, and countries with similar characteristics (countries that have sustained economic development, sufficient liquidity for listed companies and accessible markets). The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposures comparable, in the judgment of the Adviser, to investments in equity securities of issuers in developing economies or securities markets may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least 60 days' notice prior to any change in this 80% investment policy.

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base; (iii) the location of the issuer's headquarters; (iv) the geographic distribution of the issuer's operations (in terms of assets and revenues); (v) the issuer's history with respect to these criteria; and (vi) the country in which investors consider the issuer to be most appropriately classified based on communications between the Index Provider and investors.

State Street International Developed Equity Index Fund

Principal Investment Strategies

In seeking to track the performance of the Index, the Fund expects to employ a sampling strategy, which means that the Fund will not typically purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index or other investments in an effort to create a portfolio of securities with generally the same risk and return characteristics of the Index. The number of holdings in the Fund will be based on a number of factors, including the asset size of the Fund. Based on its analysis of these factors, SSGA FM may, instead, invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index.

Under normal circumstances, the Fund invests substantially all, but as a matter of policy no less than 80%, of its net assets (plus borrowings, if any) in securities, or American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”) based on securities, comprising the Index, or in other funds, including funds sponsored by the Adviser or its affiliates, or in other investments, that the Adviser expects to provide a return highly correlated to the Index or a portion of the Index. The notional value of the Fund's investments in derivatives or other synthetic instruments that provide exposure comparable, in the judgment of the Adviser, to the foregoing types of investments may be counted toward satisfaction of this 80% policy. The Fund will provide shareholders with at least sixty (60) days' notice prior to any change in its policy to invest at least 80% of its assets as described in the foregoing. The Fund may invest in equity securities that are not included in the Index (including common stock, preferred stock, depositary receipts and shares of other investment companies), cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser). The Fund may use derivatives, including futures contracts and options, swaps, and contracts for differences, to obtain investment exposures that the Adviser expects to correlate closely with the Index or a portion of the Index.

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to $367.52 billion. As of February 28, 2022, countries covered in the Index included Australia, Austria, Belgium, Denmark, Finland, France, Germany, Hong Kong, Ireland, Israel, Italy, Japan, the Netherlands, New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland and the United Kingdom, although this may change from time to time.

Additional Information About Risks

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financial institution (or an affiliate of the financial institution) experiences financial difficulties, then the Fund may in certain situations be prevented or delayed from exercising its rights to terminate the investment or transaction, or to realize on any collateral and may result in the suspension of payment and delivery obligations of the parties under such investment or transactions or in another institution being substituted for that financial institution without the consent of the Fund. Further, a Fund may be subject to “bail-in” risk under applicable law whereby, if required by the financial institution's authority, the financial institution's liabilities could be written down, eliminated or converted into equity or an alternative instrument of ownership. A bail-in of a financial institution may result in a reduction in value of some or all of its securities and, if a Fund holds such securities or has entered into a transaction with such a financial security when a bail-in occurs, such Fund may also be similarly impacted.

Currency Hedging Risk (principal risk for the Hedged International Developed Equity Index Fund). When a derivative is used as a hedge against a position that a Fund holds, any gain generated by the derivative generally should be substantially offset by losses on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between a derivative and its reference asset. For example, because the Fund's currency hedge is reset on a monthly basis, based on the size of the Fund's exposure to a currency at a certain point in time, the size of each currency hedge could be greater or less than the Fund's total exposure in that currency intra-month and currency risk may develop or increase between resets. Furthermore, while the Fund is designed to hedge against currency fluctuations, it is possible that a degree of currency exposure may remain even at the time a hedging transaction is implemented. As a result, changes in currency exchange rates may affect Fund returns even when the hedge works as intended. The effectiveness of a Fund's currency hedging strategy will also generally be affected by the volatility of both the securities included in the Index, and the volatility of the U.S. dollar relative to the currencies to be hedged. Increased volatility may reduce the effectiveness of a Fund's currency hedging strategy and may impact the costs associated with hedging transactions. The effectiveness of a Fund's currency hedging strategy and the costs associated with hedging transactions may also in general be affected by interest rates. Significant differences between U.S. dollar interest rates and foreign currency interest rates may further impact the effectiveness of a Fund's currency hedging strategy. There can be no assurance that a Fund's hedging transactions will be effective. A Fund's currency hedging activities will potentially increase or accelerate distributions to shareholders, increase distributions taxed to individuals as ordinary income, result in the re-characterization of prior ordinary income distributions as return of capital, or generate losses that cannot be used to offset income or capital gain in subsequent years. A Fund will bear the costs associated with any such hedging transaction, regardless of any gain or loss experienced on the hedging transaction.

Currency Risk. Investments in issuers in different countries are often denominated in currencies other than the U.S. dollar. Changes in the values of those currencies relative to the U.S. dollar may have a positive or negative effect on the values of a Fund's investments denominated in those currencies. The values of other currencies relative to the U.S. dollar may fluctuate in response to, among other factors, interest rate changes, intervention (or failure to intervene) by national governments, central banks, or supranational entities such as the International Monetary Fund, the imposition of currency controls, and other political or regulatory developments. Currency values can decrease significantly both in the short term and over the long term in response to these and other developments. Continuing uncertainty as to the status of the Euro and the Economic and Monetary Union of the European Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU, or any continued uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's portfolio investments. With respect to the Hedged International Developed Equity Index Fund, to the extent the Adviser seeks to hedge against adverse changes in the values of currencies on the value of the Fund's assets, such hedging transactions may not have the desired effect or may cause the Fund to lose money.

Depositary Receipts Risk. American Depositary Receipts (“ADRs”) are typically trust receipts issued by a U.S. bank or trust company that evidence an indirect interest in underlying securities issued by a foreign entity. Global Depositary Receipts (“GDRs”), European Depositary Receipts (“EDRs”), and other types of depositary receipts are typically issued by non-U.S. banks or financial institutions to evidence an interest in underlying securities issued by either a U.S. or a non-U.S. entity. Investments in non-U.S. issuers through ADRs, GDRs, EDRs, and other types of depositary receipts generally involve risks applicable to other types of investments in non-U.S. issuers. Investments in depositary receipts may be less liquid and more volatile than the underlying securities in their primary trading market. If a depositary receipt is denominated in a different currency than its underlying securities, a Fund will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. There may be less publicly available information regarding the issuer of the securities underlying a depositary receipt than if those securities were traded directly in U.S. securities markets. Depositary receipts may or may not be sponsored by the issuers of the underlying securities, and

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information regarding issuers of securities underlying unsponsored depositary receipts may be more limited than for sponsored depositary receipts. The values of depositary receipts may decline for a number of reasons relating to the issuers or sponsors of the depositary receipts, including, but not limited to, insolvency of the issuer or sponsor. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based. To the extent the Fund invests in depositary receipts based on securities included in the Index, such differences in prices may increase index tracking risk.

Equity Investing Risk. The market prices of equity securities owned by a Fund may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer, such as management performance, financial leverage, non-compliance with regulatory requirements, and reduced demand for the issuer's goods or services. The values of equity securities also may decline due to general industry or market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, or adverse investor sentiment generally. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

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and required government intervention to survive. The British economy relies heavily on the export of financial services to the United States and other European countries and, therefore, a prolonged slowdown in the financial services sector may have a negative impact on the British economy. Continued governmental involvement or control in certain sectors may stifle competition in certain sectors or cause adverse effects on economic growth. In the past, the United Kingdom has been a target of terrorism. Acts of terrorism in the United Kingdom or against British interests abroad may cause uncertainty in the British financial markets and adversely affect the performance of the issuers to which a Fund has exposure.

Indexing Strategy/Index Tracking Risk. The Fund is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities. The Fund will seek to replicate Index returns, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. The Fund generally will buy and will not sell a security included in the Index as long as the security is part of the Index regardless of any sudden or material decline in value or foreseeable material decline in value of the security, even though the Adviser may make a different investment decision for other actively managed accounts or portfolios that hold the security. As a result, a Fund's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index (in absolute terms and by comparison with other indices) and, consequently, the performance, volatility, and risk of a Fund. Errors in index data, index computations or the construction of the Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on a Fund and its shareholders. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), a Fund's return may not match the return of the Index for a number of reasons. For example, the return on the sample of securities purchased by a Fund (or the return on securities not included in the Index) to replicate the performance of the Index may not correlate precisely with the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, a Fund may not be fully invested at times, either as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to track the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between a Fund's return and that of the Index. Changes in the composition of the Index and regulatory requirements also may impact a Fund's ability to match the return of the Index. The Adviser may apply one or more “screens” or investment techniques to refine or limit the number or types of issuers included in the Index in which a Fund may invest. Application of such screens or techniques may result in investment performance below that of the Index and may not produce results expected by the Adviser. Index tracking risk may be heightened during times of increased market volatility or other unusual market conditions.

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pounded. This is because leverage generally creates investment risk with respect to a larger base of assets than a Fund would otherwise have and so magnifies the effect of any increase or decrease in the value of the Fund's underlying assets. The use of leverage is considered to be a speculative investment practice and may result in losses to a Fund. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The use of leverage may cause a Fund to liquidate positions when it may not be advantageous to do so to satisfy repayment, interest payment, or margin obligations or to meet asset segregation or coverage requirements.

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and on the values of a Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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Master/Feeder Structure Risk (principal risk for the International Developed Equity Index Fund). The Fund pursues its objective by investing substantially all of its assets in another pooled investment vehicle (a “master fund”). The ability of a Fund to meet its investment objective is directly related to the ability of the master fund to meet its investment objective. The ability of a Fund to meet its objective may be adversely affected by the purchase and redemption activities of other investors in the master fund. The ability of a Fund to meet redemption requests will depend on its ability to redeem its interest in the master fund. The Adviser or an affiliate serves as investment adviser to the master fund, leading to potential conflicts of interest. For example, the Adviser or its affiliates will receive fees based on the amount of assets invested in the master fund. Investment by a Fund in the master fund may be beneficial in the management of the master fund, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a master fund sponsored or managed by the Adviser or its affiliates in lieu of investments by a Fund directly in portfolio securities, or may have an incentive to invest in such master fund over a master fund sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a master fund sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a master fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so. A Fund will bear its pro rata portion of the expenses incurred by the master fund.

Mid-Capitalization Securities Risk. The securities of mid-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of mid-sized companies may trade less frequently and in smaller volumes than more widely held securities. The prices of these securities may fluctuate more sharply than those of other securities, and a Fund may experience some difficulty in establishing or closing out positions in these securities at prevailing market prices. There may be less publicly available information about the issuers of these securities or less market interest in these securities than in the case of larger companies, both of which can cause significant price volatility. Some securities of mid-sized issuers may be illiquid or may be restricted as to resale. Returns on investments in securities of mid-capitalization companies could trail the returns on investments in securities of larger or smaller companies.

Non-U.S. Securities Risk. Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Because non-U.S. securities are typically denominated and traded in currencies other than the U.S. dollar, the value of the Fund's assets, to the extent they are non-U.S. dollar denominated, may be affected favorably or unfavorably by currency exchange rates, exchange control regulations, and restrictions or prohibitions on the repatriation of non-U.S. currencies. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Fund invests could cause the Fund's investments in that country to experience gains or losses.

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traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Settlement Risk. Markets in different countries have different clearance and settlement procedures and in certain markets there have been times when settlements have been unable to keep pace with the volume of transactions. Delays in settlement may increase credit risk to a Fund, limit the ability of a Fund to reinvest the proceeds of a sale of securities, hinder the ability of a Fund to lend its portfolio securities, and potentially subject a Fund to penalties for its failure to deliver to on-purchasers of securities whose delivery to a Fund was delayed. Delays in the settlement of securities purchased by a Fund may limit the ability of a Fund to sell those securities at times and prices it considers desirable, and may subject a Fund to losses and costs due to its own inability to settle with subsequent purchasers of the securities from it. A Fund may be required to borrow monies it had otherwise expected to receive in connection with the settlement of securities sold by it, in order to meet its obligations to others. Limits on the ability of a Fund to purchase or sell securities due to settlement delays could increase any variance between a Fund's performance and that of its benchmark index.

Underlying Fund Risk (principal risk for the Hedged International Developed Equity Index Fund). The Fund currently intends to gain all of its investment exposure to, and track the performance of, the Index constituents by investing in another pooled investment vehicle (an “underlying fund”). The ability of the Fund to meet its investment objective with respect to the Index constituents is directly related to the ability of the underlying fund to meet its investment objective. The ability of the Fund to meet its objective may be adversely affected by the purchase and redemption activities of other investors in the underlying fund. The ability of the Fund to meet redemption requests will depend on its ability to redeem its interest in the underlying fund. The Adviser serves as investment adviser to the underlying fund, leading to potential conflicts of interest. For example, the Adviser or its affiliates will receive fees based on the amount of assets invested in the underlying fund. Investment by the Fund in the underlying fund may be beneficial in the management of the underlying fund, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest the Fund's assets in a master fund sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in such underlying fund over a underlying fund sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by the Fund in a underlying fund sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a underlying fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so. The Fund will bear its pro rata portion of the expenses incurred by the underlying fund.

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Additional Information About Non-Principal Investment Strategies and Risks

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds and the Portfolio) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund and its service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

The International Developed Equity Index Fund invests through a “master-feeder” structure. The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Portfolio, a separate mutual fund, that has substantially similar investment strategies and risks as the Fund. Descriptions of the investment activities of the Fund also generally describe the expected investment activities of the Portfolio. The Hedged International Developed Equity Index Fund gains all of its investment exposure to the Index constituents by investing in the Portfolio, a separate mutual fund that, aside from the currency hedging activities performed by the Fund, has substantially similar investment strategies and risks as the Fund. Descriptions of the investment activities of the Fund also generally describe the expected investment activities of the Portfolio. Either Fund can withdraw its investment in the Portfolio if, at any time, the Fund's Board of Trustees determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives or strategies of the Portfolio changed so that they were inconsistent with the objectives or strategies of the Fund. If a Fund withdraws its investment from the Portfolio, the Fund may invest all of its assets in another mutual fund that has substantially similar investment strategies to those of the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

State Street Hedged International Developed Equity Index Fund	0.14%
State Street International Developed Equity Index Fund	0.11%

The amount each Fund pays under its Investment Advisory Agreement is reduced by the amount of the advisory fee it bears indirectly through its investment in the Portfolio. For the services provided under its Investment Advisory Agreement, the Portfolio pays the Adviser a management fee at an annual rate of 0.11% of the Portfolio's average daily net assets.

Total Annual Fund Operating Expense Waiver. For the Hedged International Developed Equity Index Fund, SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees other than the fees of the Portfolio, and any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.15% of average daily net assets on an annual basis. Additionally, for the International Developed Equity Index Fund, SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, and any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed 0.09% of average daily net assets on an annual basis. These waiver and/or reimbursement arrangements may not be terminated prior to April 30, 2023 except with approval of the Funds' Board of Trustees.

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A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021 for the Hedged International Developed Equity Index Fund and, for the International Developed Equity Index Fund, will be included in that Fund's annual report or semi-annual report, as applicable, after that Fund commences operations.

Key professionals involved in the day-to-day portfolio management of the Funds include the following:

David Chin is a Vice President of SSGA and the Adviser and a Senior Portfolio Manager in the Global Equity Beta Solutions Group. He is responsible for managing a full range of equity index and tax-efficient products. Prior to joining SSGA in 1999, Mr. Chin worked at Frank Russell Company, OneSource Information Systems, and PanAgora Asset Management. Mr. Chin has been working in the investment management field since 1992. Mr. Chin holds a Bachelor of Science in Management Information Systems from the University of Massachusetts/Boston and a Master of Business Administration from the University of Arizona.

Additional information about the portfolio managers' compensation, other accounts managed by the portfolio managers, and the portfolio managers' ownership of the Funds is available in the SAI.

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Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% with respect to each of its share classes. State Street, a subsidiary of State Street Corporation, serves as sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

Shareholder Information

Determination of Net Asset Value

Each Fund determines its NAV per share once each business day as of the scheduled close of regular trading on the New York Stock Exchange (the “NYSE”). Pricing does not occur on NYSE holidays. A business day is one on which the NYSE is open for regular trading. The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. In unusual circumstances, such as an emergency or an unscheduled close or halt of trading on the NYSE, the time at which share prices are determined may be changed. The NAV per share is based on the market value of the investments held in a Fund. The NAV of each class of a Fund's Shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding.As noted in this Prospectus, each Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when each Fund does not price its shares. Consequently, the NAV of each Fund's Shares may change on days when shareholders are not able to purchase or redeem the Fund's Shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. Each Fund values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Funds' Board, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by a Fund occurs after the close of a related exchange but before the determination of a Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent

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that a Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published NAVs per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

Choosing a Share Class

The Funds offer three classes of shares through this Prospectus: Class A, Class I and Class K, available to you subject to the eligibility requirements set forth below.

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	Class A	Class I	Class K
Availability	Available to the general public through certain Financial Intermediaries.	Limited to certain investors serviced through a Financial Intermediary receiving a fee from the applicable Fund for shareholder servicing or similar services.	Limited to certain investors, including certain qualified recordkeepers, financial institutions and employer-sponsored retirement plans.
Minimum Initial Investment	$2,000. The investment minimum may be modified, waived or reduced for certain types of investors (e.g., 401(k) or 403(b) plans) and investments as well as for certain fee-based programs where an agreement is in place.	There is no minimum investment for Class I shares.	There is no minimum investment for Class K shares.
Maximum Investment	None.	None.	None.
Initial (Front-End) Sales Charge	Yes. 5.25%, payable at time of purchase. Lower sales charges are available for larger investments. See the chart under “Class A” section of this Prospectus.	No. Entire purchase price is invested in shares of a Fund.	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No, except for purchases of $1,000,000 or more that are redeemed within 18 months after purchase.	No.	No.
Distribution and Service (Rule 12b-1) Fees	0.25% annual fee.	No.	No.
Redemption Fees	No.	No.	No.

Class A

Class A shares are available to the general public for investment through qualified recordkeepers with a distribution and/or fund servicing agreement maintained with SSGA FD.

When you buy Class A shares, you pay an initial (or front-end) sales charge at the time of your investment, which is included in the offering price, unless you qualify for a sales charge reduction or waiver. This fee is deducted from the amount you invest, and the remainder of your money is used to buy shares in the Fund. The table below shows the amount of sales charge you would pay at different levels of investment and the commissions paid to Financial Intermediaries at each level of investment. The actual sales charge you pay may vary slightly from the rates disclosed due to rounding.

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Amount of Purchase Payment	Sales Charge as a % of Offering Price	Sales Charge as a % of Net Amount Invested	Financial Intermediary Compensation as a % of Offering Price
Less than $50,000	5.25%	5.54%	4.75%
$50,000-$99,999	4.50%	4.71%	4.00%
$100,000-$249,999	3.50%	3.63%	3.25%
$250,000-$499,999	2.50%	2.56%	2.25%
$500,000-$999,999	2.00%	2.04%	1.75%
$1,000,000 or more	None	None	Advanced Commission^{1, 2}

¹	Class A advanced commission for purchases over $1 million:

1.00%	First $3 million
Plus 0.50%	Next $12 million
Plus 0.25%	Over $15 million

Reducing Your Class A Sales Charge

1.	Your account(s);
2.	Account(s) of your spouse or domestic partner;
3.	Account(s) of children under the age of 21 who share your residential address;
4.	Trust accounts established by any of the individuals in items (1) through (3) above. If the person(s) who established the trust is deceased, the trust account may be aggregated with the account(s) of the primary beneficiary of the trust;
5.	Solely controlled business accounts; and
6.	Single-participant retirement plans of any of the individuals in items (1) through (3) above.

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Waiver Of The Class A Sales Charge

A sales charge (“load”) may not be imposed on Class A shares of the Funds if the shares were:

1.	Acquired through the reinvestment of dividends and capital gain distributions.
2.	Acquired in exchange for shares of another Class A State Street Fund that were previously assessed a sales charge. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares at the same CDSC rate.
3.	Bought in State Street Funds that do not offer Class N (no load) shares¹ by officers, directors or trustees, retirees and employees and their immediate family members (i.e., spouses, domestic partners, children, grandchildren, parents, grandparents, and any dependent of the person, as defined in Section 152 of the Internal Revenue Code of 1986 (the “Code”)) of:

•	The State Street Funds
•	State Street Corporation and its subsidiaries and affiliates

4.	Bought by employees of:

•

DST Asset Manager Solutions, Inc. and its subsidiaries and affiliates.

•

¹	State Street Funds that offer Class N Shares include: State Street Defensive Emerging Markets Equity Fund (SSEMX), State Street International Stock Selection Fund (SSAIX) and State Street S&P 500 Index Fund (SVSPX).

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5.	Bought by:

•	Authorized retirement plans serviced or sponsored by a Financial Intermediary, provided that such Financial Intermediary has entered into an agreement with SSGA FD or with the Fund with respect to such purchases at NAV.
•	Investors who are directly rolling over or transferring shares from an established State Street Fund or State Street qualified retirement plan. Rolling over or transferring shares involves the transferring of shares (in-kind); there is no cash movement associated with the transaction.
•	Clients of Financial Intermediaries that (i) charge an ongoing fee for advisory, management, consulting or similar services, or (ii) have entered into an agreement with SSGA FD to offer Class A shares through a no-load network or platform, or self-directed brokerage accounts that may or may not charge transaction fees to customers.
•	Insurance company separate accounts.
•	Tuition Programs that qualify under Section 529 of the Code.

6.	Bought with proceeds from the sale of Class A shares of a State Street Fund, but only if the purchase is made within 90 days of the sale or distribution. Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.
7.	Bought in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which a Fund is a party. However, you may pay a CDSC when you sell the Fund Shares you received in connection with the plan of reorganization.

Additional Sales Charge Waiver Disclosure

How the CDSC is Calculated

The State Street Funds calculate the CDSC by treating all purchases made in a given month as though they were made on the first day of the month.

You should retain any records necessary to substantiate historical costs because SSGA FD, the Funds, the transfer agent and your Financial Intermediary may not maintain such information.

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Waiver of the CDSC

In the following situations, no CDSC is imposed on redemptions of Class A shares of the Funds:

1.	If you participate in the Automatic Withdrawal Plan. Redemptions made on a regular periodic basis (e.g. monthly) will not be subject to any applicable CDSC if they are, in the aggregate, less than or equal to 10% annually of the current market value of the account balance. Redemptions made as part of a required minimum distribution are also included in calculating amounts eligible for this waiver. For information on the Automatic Withdrawal Plan, please see Service Options.
2.	If you are a registered participant or beneficial owner of an account and you die or become disabled (as defined in Section 72(m)(7) of the Code). This waiver is only available for accounts open prior to the shareholder's or beneficiary's death or disability, and the redemption must be made within one year of such event. Subsequent purchases into such account are not eligible for the CDSC waiver. In order to qualify for this waiver, SSGA FD must be notified of such death or disability at the time of the redemption order and be provided with satisfactory evidence of such death or disability.
3.	Redemptions that represent a required minimum distribution from your IRA Account or other qualifying retirement plan but only if you are at least age 72 or age 70 ½ if you reached age 70 ½ prior to January 1, 2020. If you maintain more than one IRA, only the assets credited to the IRA that is invested in one or more of the State Street Funds are considered when calculating that portion of your minimum required distribution that qualifies for the waiver.
4.	A distribution from a qualified retirement plan by reason of the participant's retirement.
5.	Redemptions that are involuntary and result from a failure to maintain the required minimum balance in an account.
6.	Exchanges in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which a Fund is a party. However, you may pay a sales charge when you redeem the Fund Shares you receive in connection with the plan of reorganization.
7.	Exchanges for shares of the same class of another State Street Fund. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares. For purposes of the CDSC, shares will continue to age from the date of the original purchase of the Fund Shares.
8.	Redemption of shares purchased through employer sponsored retirement plans and deferred compensation plans. The CDSC, however, will not be waived if the plan redeems all of the shares that it owns on behalf of participants prior to the applicable CDSC period, as defined above.
9.	Redemptions as part of annual IRA custodial fees.
10.	Acquired through the reinvestment of dividends and capital gains distributions.

Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.

Class A Account Reinstatement Privileges

Class I

Class I shares are available to the following categories of investors serviced through a Financial Intermediary receiving a fee from a Fund for shareholder servicing or similar services:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) that have entered into agreements with the Fund to purchase Class I shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund “supermarkets”;
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Defined contribution, defined benefit and other employer-sponsored employee benefit plans, whether or not qualified under the Code.

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There is no minimum investment for Class I shares.

Class K

Class K shares are available to the following categories of investors:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) purchasing Fund Shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund "supermarkets";
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Qualified recordkeepers with an applicable agreement maintained with SSGA FD;
3.	Endowments and foundations, and defined contribution, defined benefit, and other employer-sponsored employee benefit plans, whether or not qualified under the Code;
4.	Certain other registered open-end investment companies whose shares are distributed by SSGA FD;
5.	Current or retired Directors or Trustees of the State Street Funds, officers and employees of SSGA, and any of its subsidiaries, such persons' spouses, and children under the age of 21, and trust accounts for which any of such person is a beneficiary;
6.	Qualified state tuition plans described in Section 529 of the Code and donor-advised charitable gift funds (subject to all applicable terms and conditions);
7.	Health Savings Accounts under Section 223 of the Code if such accounts are maintained by the Fund at an omnibus level;
8.	Collective investment trusts.

There is no minimum investment for Class K shares.

How to Initiate a Purchase Request

Investing in the State Street Funds Through a Financial Intermediary

Account Applications and Other Documents. You may find many of the forms necessary to open an account online or by calling or writing to the State Street Funds. See Contacting the State Street Funds.

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Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

How to Pay for a Purchase

By Check. You may send a check to make initial or additional purchases to your fund account. Make your check payable to “State Street Funds” and include the appropriate fund name and account number (e.g., “State Street Hedged International Developed Equity Index Fund—a/c #xxx”) in the memo section of the check.

Trade Dates-Purchases

If your purchase request is not in good order, it may be rejected.

For further information about purchase transactions, consult our website at www.ssga.com or see Contacting the State Street Funds.

Other Purchase Policies You Should Know

Redeeming Shares

By Telephone. You may call the State Street Funds to request a redemption of shares. See Contacting the State Street Funds.

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By Mail. You may send a written request to the State Street Funds to redeem from a Fund account or to make an exchange. See Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

Trade Date-Redemptions

The trade date for any redemption request received in good order will depend on the day and time the State Street Funds receive your request in good order and the manner in which you are redeeming.

How to Receive Redemption Proceeds

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Other Redemption Policies that You Should Know

Address Changes. If your address of record has been changed within thirty (30) days of the redemption request, the request must be in writing and bear a medallion guarantee.

Significant/Unusual Economic or Market Activity. During periods of significant or unusual economic or market activity, you may encounter delays attempting to give instructions by phone.

Exchanging Shares

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Share Class Conversions

Frequent-Trading Limits

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;
•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Funds against harmful short-term trading; and
•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

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The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Service Options

Dividend and Capital Gain Distribution Option

Please refer to Dividends, Distributions and Tax Considerations below for additional information.

Automatic Withdrawal Plan

Telephone Redemptions and Exchanges

Automatic Investment Plan

Additional Shareholder Information

Account Transfers

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Responsibility for Fraud

Right to Change Policies

In addition to the rights expressly stated elsewhere in this Prospectus, the State Street Funds reserve the right, in the future, to:

1.	Alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, service, or privilege at any time;
2.	Accept initial purchases by telephone;
3.	Freeze any account and/or suspend account services if the State Street Funds has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if we reasonably believe a fraudulent transaction may occur or has occurred;
4.	Temporarily freeze any account and/or suspend account services upon initial notification to the State Street Funds of the death of the shareholder until the State Street Funds receive required documentation in good order;
5.	Alter, impose, discontinue, or waive any redemption fee, account service fee, or other fees charged to a group of shareholders; and
6.	Redeem an account or suspend account privileges, without the owner's permission to do so, in cases of threatening conduct or activity the State Street Funds believe to be suspicious, fraudulent, or illegal.

Unclaimed Property

Dividends, Distributions and Tax Considerations

Distribution Options. You can choose from four different distribution options as indicated on the application:

•	Reinvestment Option—Dividends and capital gain distributions will be automatically reinvested in additional shares of a Fund. If you do not indicate a choice on the application, this option will be automatically assigned.
•	Income-Earned Option—Capital gain distributions will be automatically reinvested, but a check, direct deposit or wire will be sent for each dividend distribution.
•	Cash Option—A check, wire or direct deposit will be sent for each dividend and capital gain distribution.
•	Direct Dividends Option—Dividends and capital gain distributions will be automatically invested in another identically registered State Street Fund of the same share class.

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Delivery of Documents to Accounts Sharing an Address

Tax Considerations

Each Fund invests substantially all of its assets in the Portfolio, which is treated as a partnership for U.S. federal income tax purposes, and the Hedged International Developed Equity Index Fund will use the balance of its assets to enter into foreign currency forward contracts, foreign currency futures and options, and currency swaps or purchase currency structured notes, in order to hedge the non-U.S. currency exposure created by the Portfolio's investment in foreign equities to the U.S. dollar. Because each Fund invests substantially all of its assets in the Portfolio, the nature and character of each Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and each Fund will be allocated its share of the Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of a Fund will include references to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of a Fund will include references to the Fund's allocable share of the assets of the Portfolio.

For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Fund or Portfolio owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that a Fund or the Portfolio owned (or is deemed to have owned) for more than one year that are properly reported by a Fund as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that a Fund or Portfolio owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income. Distributions of investment income properly reported by a Fund as derived from “qualified dividend income,” which will not include income from the Fund's or the Portfolio's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by both the shareholder and the Fund or the Portfolio, as applicable. Distributions are taxable to you even if they are paid from income or gains earned by a Fund, including through the Portfolio, before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of a Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Fund's shares, and, in general, as capital gain thereafter.

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A Fund's and the Portfolio's income from or proceeds of dispositions of its investments in non-U.S. assets may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. In certain instances, a Fund may be entitled to elect to pass through to its shareholders a credit (or deduction, for a shareholder that itemizes deductions and so chooses) for foreign taxes (if any) borne with respect to foreign securities income earned by the Fund or the Portfolio. If the Fund so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the Fund. There can be no assurance that a Fund will make such election, even if it is eligible to do so. If a Fund does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Fund; in that case the foreign tax will nonetheless reduce the Fund's taxable income. Shareholders that are not subject to U.S. federal income tax, and those who invest in a Fund through tax-advantaged accounts (including those who invest through IRAs or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit or deduction passed through by the Fund. Under certain circumstances, if a Fund receives a refund of foreign taxes paid in respect of a prior year, the value of Fund Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Fund's foreign taxes for the current year could be reduced.

Certain of a Fund's or the Portfolio's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of the Portfolio's or Fund's income or gains, and, in turn, a Fund's distributions to shareholders, and may require the Fund or the Portfolio to sell its investments at a time when it is not advantageous to do so.

In particular, the Hedged International Developed Equity Index Fund's transactions in respect of foreign currencies will potentially give rise to ordinary income and loss to the extent such income or loss results from fluctuations in the value of the foreign currency concerned. Such activities will potentially increase distributions to shareholders, including at the end of the year, accelerate distributions to shareholders, and increase the distributions taxed to shareholders as ordinary income. Moreover, any net losses arising from such activities will generally reduce and potentially require the recharacterization of prior ordinary income distributions, including in whole or in part as a return of capital. Any net ordinary losses so created cannot be carried forward by the Fund to offset income or gains earned in subsequent taxable years. The Hedged International Developed Equity Index Fund makes an election to treat currency gains and losses derived from certain eligible foreign currency forward contracts as capital gains and losses. It is possible that the Hedged International Developed Equity Index Fund will elect, on a prospective basis, to treat currency gains and losses derived from futures contracts or options as capital gains and losses; not all currency gains and losses derived from foreign currency contracts are eligible for this treatment.

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Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

A Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of that Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

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Financial Highlights

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET HEDGED INTERNATIONAL DEVELOPED EQUITY INDEX FUND FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	State Street Hedged International Developed Equity Index Fund Class K
	Year Ended 12/31/21	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	Year Ended 12/31/17(a)
Net asset value, beginning of period	$104.85	$104.30	$87.90	$104.00	$91.80
Income (loss) from investment operations:
Net investment income (loss) (b)	2.93	2.15	3.10	2.90	2.70
Net realized and unrealized gain (loss)	17.33	0.53	18.60	(12.60)	12.70
Total from investment operations	20.26	2.68	21.70	(9.70)	15.40
Distributions to shareholders from:
Net investment income	(3.56)	(2.13)	(3.20)	(5.00)	—
Net realized gains	—	—	(2.10)	(1.40)	(3.20)
Total distributions	(3.56)	(2.13)	(5.30)	(6.40)	(3.20)
Net asset value, end of period	$121.55	$104.85	$104.30	$87.90	$104.00
Total return (c)	19.31%	2.45%	24.82%	(9.25)%	16.85%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$4,512,062	$3,684,209	$3,772,743	$2,922,844	$2,894,400
Ratios to Average Net Assets:
Total expenses	0.35%	0.36%	0.36%	0.36%	0.35%
Net expenses	0.20%	0.20%	0.20%	0.20%	0.20%
Net investment income (loss)	2.50%	2.23%	3.08%	2.85%	2.69%
Portfolio turnover rate (d)	7%	8%	3%	14%	4%

(a)	On April 17, 2020, the State Street Hedged International Developed Equity Index Fund underwent a 1-for-10 reverse share split. The historical per share activity presented here has been retroactively adjusted to reflect this split.
(b)	Net investment income per share is calculated using the average shares method.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Portfolio turnover rate is from the corresponding Portfolio.

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Index/Trademark Licenses/Disclaimers

THE FUNDS ARE NOT SPONSORED, ENDORSED, SOLD OR PROMOTED BY MSCI INC. (“MSCI”), MSCI'S PARENT COMPANY, ANY OF MSCI'S OR MSCI'S PARENT COMPANY'S DIRECTLY OR INDIRECTLY HELD SUBSIDIARIES, ANY OF MSCI'S OR MSCI'S PARENT COMPANY'S INFORMATION PROVIDERS OR ANY THIRD PARTY INVOLVED IN, OR RELATED TO, COMPILING, COMPUTING OR CREATING ANY MSCI INDEX (COLLECTIVELY, THE “MSCI PARTIES”).THE MSCI INDICES ARE THE EXCLUSIVE PROPERTY OF MSCI. MSCI AND THE MSCI INDEX NAMES ARE SERVICE MARK(S) OF MSCI OR ITS AFFILIATES AND HAVE BEEN LICENSED FOR USE FOR CERTAIN PURPOSES BY THE LICENSEE. NONE OF THE MSCI PARTIES MAKES ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY REGARDING THE ADVISABILITY OF INVESTING IN FUNDS GENERALLY OR IN THE MSCI FUNDS PARTICULARLY OR THE ABILITY OF ANY MSCI INDEX TO TRACK CORRESPONDING STOCK MARKET PERFORMANCE. MSCI OR ITS AFFILIATES ARE THE LICENSORS OF CERTAIN TRADEMARKS, SERVICE MARKS AND TRADE NAMES AND OF THE MSCI INDICES WHICH ARE DETERMINED, COMPOSED AND CALCULATED BY MSCI WITHOUT REGARD TO THE MSCI FUNDS OR THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY. NONE OF THE MSCI PARTIES HAS ANY OBLIGATION TO TAKE THE NEEDS OF THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY INTO CONSIDERATION IN DETERMINING, COMPOSING OR CALCULATING THE MSCI INDICES. NONE OF THE MSCI PARTIES IS RESPONSIBLE FOR OR HAS PARTICIPATED IN THE DETERMINATION OF THE TIMING OF, PRICES AT, OR QUANTITIES OF THE MSCI FUNDS TO BE ISSUED OR IN THE DETERMINATION OR CALCULATION OF THE EQUATION BY OR THE CONSIDERATION INTO WHICH THE MSCI FUNDS ARE REDEEMABLE. FURTHER, NONE OF THE MSCI PARTIES HAS ANY OBLIGATION OR LIABILITY TO THE ISSUER OR OWNERS OF THE MSCI FUNDS OR ANY OTHER PERSON OR ENTITY IN CONNECTION WITH THE ADMINISTRATION, MARKETING OR OFFERING OF THE MSCI FUNDS.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. In a Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund's performance during its last fiscal year. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports is available or will be available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (800) 997-7327 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, or will be available, free of charge, on the Funds' website at www.ssga.com.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITSTATPRO2

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Institutional Liquid Reserves Fund

Trust Class (TILXX)

State Street Institutional Treasury Plus Money Market Fund

Trust Class (TPLXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Trust Class Shares of the applicable Funds.

State Street Institutional Liquid Reserves Fund is a “floating net asset value” money market fund. The share price of this Fund will fluctuate.

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Fund Summaries	1
State Street Institutional Liquid Reserves Fund	1
State Street Institutional Treasury Plus Money Market Fund	8
Additional Information About Investment Objectives, Principal Strategies and Risks	13
Additional Information About Non-Principal Investment Strategies and Risks	22
Portfolio Holdings Disclosure	24
Management and Organization	25
Shareholder Information	27
Dividends, Distributions and Tax Considerations	33
Financial Intermediary Arrangements	35
Financial Highlights	37

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State Street Institutional Liquid Reserves Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.13%
Total Annual Fund Operating Expenses¹	0.18%

Example:

1 year		3 years		5 years		10 years
$18		$58		$101		$230

Principal Investment Strategies

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own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

Principal Risks

The Fund is subject to the following principal risks. You could lose money by investing in the Fund. Because the share price of the Fund will fluctuate, when you sell your shares, they may be worth more or less than what you originally paid for them. The Fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares if the Fund's liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

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rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

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Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

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Performance

The bar chart and table below provide some indication of the risks of investing in the ILR Fund by illustrating the variability of the Fund's returns for Trust Class Shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.63% (Q1, 2019)
Lowest Quarterly Return: -0.01% (Q4, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Since Inception		Inception Date
Trust Class		0.00%		1.14%		1.09%		8/29/2016

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Trust Class shares of the Fund are only available for purchase by shareholders of the Fund who owned Trust Class shares on August 29, 2016.

Purchase Minimums

Trust Class
To establish an account	$15,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

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Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.13%
Total Annual Fund Operating Expenses¹	0.18%

Example:

1 year		3 years		5 years		10 years
$18		$58		$101		$230

Principal Investment Strategies

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Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns for Trust Class Shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.56% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Since Inception		Inception Date
Trust Class		0.01%		0.96%		0.91%		8/29/2016

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Trust Class shares of the Fund are only available for purchase by shareholders of the Fund who owned Trust Class shares on August 29, 2016.

Purchase Minimums

Trust Class
To establish an account	$15,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

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Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the ILR Fund and the Treasury Plus Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

ILR Fund

Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

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Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

Additional Information About Risks

Banking Companies Risk (principal risk for the ILR Fund). The performance of bank stocks may be affected by extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, and the interest rates and fees they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds, and can fluctuate significantly when interest rates change. Credit losses resulting from financial difficulties of borrowers can negatively impact the banking companies. Banks may also be subject to severe price competition. Competition among banking companies is high and failure to maintain or increase market share may result in lost market value.

Call/Prepayment Risk(principal risk for the ILR Fund). Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by a Fund earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by a Fund are prepaid. In any such case, a Fund may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Fund's income.

Counterparty Risk. A Fund will be subject to credit risk with respect to the counterparties with which a Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, a Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

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Financial Institutions Risk (principal risk for the ILR Fund). Some instruments are issued or guaranteed by financial institutions, such as banks and brokers, or are collateralized by securities issued or guaranteed by financial institutions. Changes in the creditworthiness of any of these institutions may adversely affect the values of instruments of issuers in financial industries. Financial institutions may be particularly sensitive to certain economic factors such as interest rate changes, adverse developments in the real estate market, fiscal and monetary policy and general economic cycles. Adverse developments in banking and other financial industries may cause a Fund to underperform relative to other funds that invest more broadly across different industries or have a smaller exposure to financial institutions. Changes in governmental regulation and oversight of financial institutions may have an adverse effect on the financial condition or the earnings or operations of a financial institution and on the types and amounts of businesses in which a financial institution may engage. An investor may be delayed or prevented from exercising certain remedies against a financial institution. The amount of a Fund's assets that may be invested in any financial institution, or financial institutions generally, may be limited by applicable law.

Income Risk (principal risk for the ILR Fund). A Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by a Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Fund may limit the Fund's ability to achieve its objective.

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interest rates may also have an adverse impact on the liquidity of a security, especially those with longer durations. Changes in governmental policy, including changes in central bank monetary policy, could cause interest rates to rise rapidly, or cause investors to expect a rapid rise in interest rates. This could lead to heightened levels of interest rate, volatility and liquidity risks for the fixed income markets generally and could have a substantial and immediate effect on the values of a Fund's investments.

Liquidity Risk (principal risk for the ILR Fund). Liquidity risk is the risk that a Fund may not be able to dispose of investments readily at a favorable time or prices (or at all) or at prices approximating those at which a Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Fund may seek to borrow money to meet its obligations (including among other things redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity a Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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tainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a master fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so. A Fund will bear its pro rata portion of the expenses incurred by the master fund.

Money Market Risk-Floating NAV (principal risk for the ILR Fund). The Fund does not maintain a constant net asset value per share. The value of the Fund's Shares is calculated to four decimal places and will vary reflecting the value of the portfolio of investments held by the Fund. It is possible to lose money by investing in the Fund.

Money Market Risk (principal risk for the Treasury Plus Fund). An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Although a money market fund generally seeks to preserve the value of its shares at $1.00 per share, there can be no assurance that it will do so, and it is possible to lose money by investing in a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause a money market fund's share price to fall below $1.00. It is possible that a money market fund will issue and redeem shares at $1.00 per share at times when the fair value of the money market fund's portfolio per share is more or less than $1.00. A money market fund may be permitted or required to impose redemption fees or to impose limitations on redemptions during periods of high illiquidity in the markets for the investments held by it. None of State Street Corporation, State Street, State Street Global Advisors, SSGA FM or their affiliates (collectively, the “State Street Entities”) guarantee the value of an investment in a money market fund at $1.00 per share. Investors should have no expectation of capital support to a money market fund from the State Street Entities.

Mortgage-Related and Other Asset-Backed Securities Risk (principal risk for the ILR Fund). Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically structured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. Government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk

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of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Non-U.S. Securities Risk (principal risk for the ILR Fund). Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available with regard to U.S. investments. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Fund invests could cause the Fund's investments in that country to experience gains or losses.

Rapid Changes in Interest Rates. The values of instruments held by a Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause a Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses would negatively affect the NAV per share of the ILR Fund and, in the case of the Treasury Plus Fund, could impair the Fund's ability to maintain a stable share price of $1.00.

Reinvestment Risk (principal risk for the ILR Fund). Income from a Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by a Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

Repurchase Agreement Risk. A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

Restricted Securities Risk (principal risk for the ILR Fund). A Fund may hold securities that have not been registered for sale to the public under the U.S. federal securities laws pursuant to an exemption from registration. These securities may be less liquid than securities registered for sale to the general public. The liquidity of a restricted security may be affected by a number of factors, including, among others: (i) the creditworthiness of the issuer; (ii) the frequency of trades and quotes for the security; (iii) the number of dealers willing to purchase or sell the security and the number of other potential purchasers; (iv) dealer undertakings to make a market in the security; (v) the nature of any legal restrictions governing trading in the security; and (vi) the nature of the security and the nature of marketplace trades. There can be no assurance that a liquid trading market will exist at any time for any particular restricted security. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

Risk of Investment in Other Pools(principal risk for the ILR Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value

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being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Risks Related to ECDs, ETDs and YCDs (principal risk for the ILR Fund). Banks issuing ECDs, ETDs and YCDs are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of foreign issuers also involve risks such as future unfavorable political and economic developments, withholding or other tax, seizures of foreign deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

Section 4(a)(2) Commercial Paper and Rule 144A Securities Risk (principal risk for the ILR Fund). A Fund may invest in commercial paper issued in reliance on the private placement exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the “1933 Act”). This commercial paper is commonly called “Section 4(a)(2) paper.” A Fund may also invest in securities that may be offered and sold only to “qualified institutional buyers” under Rule 144A of the 1933 Act (“Rule 144A securities”).

Stable Share Price Risk (principal risk for the Treasury Plus Fund). If the market value of one or more of the Fund's investments changes substantially, the Fund may not be able to maintain a stable share price of $1.00. This risk typically is higher during periods of rapidly changing interest rates or when issuer credit quality generally is falling, and is made worse when the Fund experiences significant redemption requests.

U.S. Government Securities Risk (principal risk for the ILR Fund). U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor sup-

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ported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of a Fund's investments.

U.S. Treasury Obligations Risk (principal risk for the Treasury Plus Fund). U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of a Fund's U.S. Treasury obligations to decline. The total public debt of the United States as a percent of gross domestic product grew rapidly after the financial crisis of 2008 and has remained at a historically high level. Although high debt levels do not necessarily indicate or cause economic problems, they may create certain systemic risks if sound debt management practices are not implemented. A high national debt level may increase market pressures to meet government funding needs, which may drive debt cost higher and cause a country to sell additional debt, thereby increasing refinancing risk. A high national debt also raises concerns that a government will not be able to make principal or interest payments when they are due. In the worst case, unsustainable debt levels can cause a decline in the value of the dollar (which may lead to inflation), and can prevent the U.S. government from implementing effective counter-cyclical fiscal policy in economic downturns. On August 5, 2011, Standard & Poor's Ratings Services downgraded U.S. Treasury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

Zero-Coupon Bond Risk (principal risk for the ILR Fund). Zero-coupon bonds are debt obligations that are generally issued at a discount and payable in full at maturity, and that do not provide for current payments of interest prior to maturity. Zero-coupon bonds usually trade at a deep discount from their face or par values and are subject to greater market value fluctuations from changing interest rates than debt obligations of comparable maturities that make current distributions of interest. When interest rates rise, the values of zero-coupon bonds fall more rapidly than securities paying interest on a current basis, because a Fund is unable to reinvest interest payments at the higher rates.

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Additional Information About Non-Principal Investment Strategies and Risks

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Funds, the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such

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third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

Risk of Investment in Other Pools (risk for the Treasury Plus Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Trust Class Closure. The Trust Class of the ILR Fund and the Treasury Plus Fund is currently closed to new investors, except as noted below.

Shareholders who owned Trust Class shares on August 29, 2016, may continue to purchase shares of the class. Fund management may, in its discretion, reopen the share class to certain investors in the future. The Fund reserves the right to modify this policy at any time.

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Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional information (“SAI”).

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Management and Organization

A Fund can withdraw its investment in a Portfolio if, at any time, the Fund's Board of Trustees (the “Board”) determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives of the corresponding Portfolio changed so that they were inconsistent with the objectives of the Fund. If a Fund withdraws its investment from a Portfolio, the Fund may invest all of its assets in another mutual fund that has the same investment objective as the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

SSGA FM serves as the investment adviser to each Fund and corresponding Portfolio and, subject to the oversight of the Board, is responsible for the investment management of each Fund. The Adviser provides an investment management program for each Fund and manages the investment of each Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the SEC under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2020, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.05% for Money Market Portfolio and 0.05% for Treasury Plus Portfolio.

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tion”). Under an agreement with the Service Providers relating to the Voluntary Reduction, the Funds and the Portfolios have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from a Fund.

A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one‑day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b‑1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

Additional Information

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Shareholder Information

Determination of Net Asset Value

For the ILR Fund

The NAV of each class of the ILR Fund's shares is calculated by dividing the value of the assets of the ILR Fund attributable to that class less the liabilities of the ILR Fund attributable to that class by the number of shares in the class outstanding. The ILR Fund values each security or other investment pursuant to guidelines adopted by the Board of Trustees. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the ILR Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent that the ILR Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

For the Treasury Plus Fund

The Treasury Plus Fund determines its NAV per share once each Business Day at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event the Treasury Plus Fund will determine its NAV at the earlier closing time (the time when the Treasury Plus Fund determines its NAV per share is referred to herein as the “Valuation Time”). The Fund seeks to maintain a $1.00 per share NAV and, accordingly, uses the amortized cost valuation method, in compliance with the risk limiting conditions of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”), to value its portfolio instruments. The amortized cost valuation method initially prices an instrument at its cost and thereafter assumes a constant amortization to maturity of any discount or premium, regardless of the impact of fluctuating interest rates on the market value of the instrument.

For all Funds

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purchase or redeem the Fund's shares. The Funds also may establish special hours on those days to determine each Fund's NAV. In the event that the Funds invoke the right to accept orders to purchase or redeem shares on any day that is not a Business Day or adopt special hours of operation, the Fund will post advance notice of these events at:www.ssga.com/cash.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

Subject to the restrictions described above under “Trust Class Closure,” investors pay no sales load to invest in the Trust Class Shares of the Fund. The price for Fund Shares is the NAV per share. Purchase requests received by a Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Times (for the ILR Fund generally, 3:00 p.m. ET, unless the Fund closes earlier), will earn dividend accrual for that purchase.

The minimum initial investment in Trust Class of the Funds is $15 million, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include, but are not limited to, accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Funds and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below).The Funds require prior notification of subsequent investments in excess of $50 million. The Funds reserve the right to cease accepting investments at any time or to reject any investment order. The Treasury Plus Fund may limit the amount of a purchase order received after 3:00 p.m. ET.

The ILR Fund determines its NAV at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The 8:00 a.m., 12:00 p.m. and 3:00 p.m. NAV calculation times are intended to facilitate same day settlement.

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How to Purchase Shares

Please see “Trust Class Closure” above regarding restrictions on purchasing shares of the Trust Class.

By Mail:

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form.

For the Treasury Plus Fund

If the Fund receives a redemption order in good form prior to 5:00 p.m. ET on a Business Day, the Fund typically expects to pay out redemption proceeds on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. No dividends will be paid on shares that are redeemed and wired the same day. If a redemption

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order is placed after 5:00 p.m. ET, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). The Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

For the ILR Fund

If the Fund receives a redemption order in good form prior to its last valuation time (generally, 3:00 p.m. ET, unless the Fund closes earlier) on a Business Day, the Fund typically sends payment for redeemed shares on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after the last valuation time (generally, 3:00 p.m. ET, unless the Fund closes earlier) the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). The Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

Certain special limitations affecting redemptions. The SEC has implemented a number of requirements, including liquidity fees and redemption gates, for money market funds based on the amount of fund assets in “weekly liquid assets,” which generally includes cash, direct obligations of the U.S. government, certain other U.S. government or agency securities, and securities that will mature or are subject to a demand feature that is exercisable and payable within five Business Days. The ILR Fund will pass through to its investors any liquidity fee or suspension of redemptions imposed by the Money Market Portfolio on the same terms and conditions as imposed by the Money Market Portfolio on the ILR Fund.

For the Treasury Plus Fund

If the Treasury Plus Fund receives a redemption order in good form prior to 5:00 p.m. ET on a Business Day, the Fund typically expects to pay out redemption proceeds on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund

typically expects to pay out redemption proceeds on the next Business Day. No dividends will be paid on shares that are redeemed and wired the same day.

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If redemption proceeds are sent by check, the Fund pays out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after 5:00 p.m. ET, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent), but no later than the following Business Day. The Fund may postpone and/or suspend redemption and payment beyond the foregoing time periods only as follows:

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;
c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

The Treasury Plus Fund is government money market funds that have not elected to be subject to the fees and gates provisions of Rule 2a-7. Although each Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

For All Funds

A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Funds reserve the right to modify minimum account requirements at any time with or without prior notice. The Funds also reserve the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Funds will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Funds calculate their NAVs earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

Same day settlement of redemption proceeds will only be available for redemption requests accepted prior to the ILR Fund's last Valuation Time of the day (generally, 3:00 p.m. ET unless the Fund closes earlier).

The Funds reserve the right to waive medallion guarantee requirements, require a medallion guarantee under other circumstances or reject or delay redemption if the medallion guarantee is not in good form. Medallion guarantees may be provided by an eligible financial institution such as a commercial bank, a FINRA member firm such as a stock broker, a savings association or a national securities exchange. A notary public cannot provide a medallion guarantee. The Funds reserve the right to reject a medallion guarantee if it is not provided by a STAMP Medallion guarantor.

The Funds may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of a Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Currently, exchanging shares is allowed from/to the Treasury Plus Fund, State Street Institutional U.S. Government Money Market Fund, and State Street Institutional Treasury Money Market Fund. Effective October 12, 2016, exchanges from/to the ILR Fund is not permitted. Exchanges may be made between different Funds within the same class (i.e. Trust Class shares for Trust Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

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to receive them in cash. No interest will accrue on the amounts represented by uncashed distribution checks. If you have elected to receive distributions by check, and the postal or other delivery service is unable to deliver the checks because of an incorrect mailing address, or if a distribution check remains uncashed for six months, the uncashed distribution and all future distributions will be reinvested at the then-current NAV of the Fund.

Each Fund invests substantially all of its investable assets in a corresponding Portfolio that is treated as a partnership for U.S. federal income tax purposes. The nature and character of each Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and each Fund will be allocated its share of the corresponding Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of a Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of a Fund will be to the Fund's allocable share of the assets of the corresponding Portfolio.

A Fund's and a Portfolio's income from or proceeds of investments in non-U.S. assets may be subject to non-U.S. withholding and other taxes. This will decrease the Fund's return on securities subject to such taxes. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes. Although such taxes will reduce a Fund's taxable income, shareholders generally will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Portfolio or Fund.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

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report any part of its dividends as are eligible for such treatment. A Fund's dividends other than those the Fund so reports as capital gain dividends, short-term capital gain dividends, or interest-related dividends generally will be subject to U.S. withholding tax at a 30% rate (or lower applicable treaty rate). See each Fund's SAI for further information.

Financial Intermediary Arrangements

Payments to Financial Intermediaries

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Third-Party Transactions. The State Street Funds have authorized certain Financial Intermediaries to accept purchase, redemption and exchange orders on the State Street Funds' behalf. Orders received for a State Street Fund by a Financial Intermediary that has been authorized to accept orders on the Fund's behalf (or other Financial Intermediaries designated by the Financial Intermediary) will be deemed accepted by the Fund at the time they are received by the Financial Intermediary and will be priced based on the Fund's next NAV determination as long as the Financial Intermediary transmits the order in good form and in a timely manner to the applicable State Street Fund(s). For the ILR Fund, the State Street Funds will be the sole party to determine if a trade is received in good order. The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to a Fund.

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Financial Highlights

The financial highlight tables are intended to help you understand each Fund's Trust Class shares financial performance since the inception date of the Trust Class shares. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in each Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with each Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of each Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Trust Class(a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0002	$1.0001	$1.0000	$0.9999	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0052	0.0226	0.0193	0.0099
Net realized and unrealized gain (loss)	(0.0001)	0.0001	(0.0003)	0.0001	(0.0001)
Total from investment operations	—	0.0053	0.0223	0.0194	0.0098
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0052)	(0.0222)	(0.0193)	(0.0099)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0052)	(0.0222)	(0.0193)	(0.0099)
Net asset value, end of period	$1.0001	$1.0002	$1.0001	$1.0000	$0.9999
Total return (c)	(0.00)%(d)	0.53%	2.26%	1.96%	0.99%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$413,169	$452,418	$597,353	$704,123	$764,391
Ratios to Average Net Assets:
Total expenses	0.18%	0.18%	0.18%	0.18%	0.18%
Net expenses	0.17%	0.18%	0.18%	0.18%	0.18%
Net investment income (loss)	0.01%	0.51%	2.26%	1.91%	0.97%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Trust Class(a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0036	0.0204	0.0168	0.0071
Net realized gain (loss)	—	—	(0.0000)(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0036	0.0204	0.0168	0.0071
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0036)	(0.0204)	(0.0168)	(0.0071)
Net realized gains	—	—	—	—	(0.0000)(b)
Total distributions	(0.0001)	(0.0036)	(0.0204)	(0.0168)	(0.0071)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.36%	2.06%	1.69%	0.71%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$3,566,204	$4,609,983	$4,185,964	$4,481,410	$6,903,267
Ratios to Average Net Assets:
Total expenses	0.17%	0.18%	0.18%	0.18%	0.18%
Net expenses	0.07%	0.16%	0.18%	0.18%	0.18%
Net investment income (loss)	0.01%	0.33%	2.05%	1.64%	0.70%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

ILRTRCLSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Institutional U.S. Government Money Market Fund: Administration Class (SALXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the Fund offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund offers multiple classes of shares. This Prospectus covers only the Administration Class Shares.

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Fund Summary	1
State Street Institutional U.S. Government Money Market Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	7
Additional Information About Non-Principal Investment Strategies and Risks	13
Portfolio Holdings Disclosure	14
Management and Organization	15
Shareholder Information	17
Dividends, Distributions and Tax Considerations	23
Financial Intermediary Arrangements	24
Financial Highlights	26

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.05%
Other Expenses¹	0.27%
Total Annual Fund Operating Expenses²	0.37%

Other expenses are based on estimates for the current fiscal year.

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), and its affiliates, may voluntarily reduce all or a portion of their fees and/or reimburse expenses of the Fund or a share class to the extent necessary to maintain a certain minimum net yield which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”), or a yield below a specified level, which may vary from time to time in the Adviser's sole discretion. The Fund has agreed, subject to certain limitations, to reimburse the Adviser and its affiliates for the full dollar amount of any Voluntary Reduction incurred beginning on May 1, 2020. During the fiscal year ended December 31, 2021, the Adviser and its affiliates waived fees and/or reimbursed expenses under the Voluntary Reduction. Each of the Adviser and its affiliates may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund. Any future reimbursement by the Fund of the Voluntary Reduction would increase the Fund's expenses and may reduce the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield.

Example:

1 year		3 years		5 years		10 years
$38		$119		$208		$468

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Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Administration Class shares from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.52% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Since Inception		Inception Date
Administration Class		0.01%		0.84%		0.78%		8/23/2016

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Administration Class
To establish an account	$1,000
To add to an existing account	No Minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

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Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

Investment Objective

The investment objective of the U.S. Government Fund, as stated in the Fund Summary, may be changed without shareholder approval.

U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

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The credit rating assigned to any particular investment does not necessarily reflect the issuer's current financial condition and does not reflect an assessment of an investment's volatility or liquidity. Securities rated in the lowest category of investment-grade are considered to have speculative characteristics. If a security held by the Fund loses its rating or its rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

Debt Securities Risk. The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

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Market Disruption and Geopolitical Risk. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of the Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of the Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by the Fund. To the extent the Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

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Rapid Changes in Interest Rates. The values of instruments held by the Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause the Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses could impair the Fund's ability to maintain a stable share price of $1.00.

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Additional Information About Non-Principal Investment Strategies and Risks

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and

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Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

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A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

Additional Information

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Shareholder Information

Determination of Net Asset Value

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

The Fund offers one class of shares through this Prospectus: Administration Class shares available to you subject to the eligibility requirements set forth below. All classes of the Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. You should choose the class with the expense structure that best meets your needs for which you are eligible. In choosing a share class, you should consider the amount you plan to invest. Your investment professional can help you choose the share class that best suits your investment needs.

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The chart below summarizes the features of the Administration Class. This chart is only a general summary, and you should read the description of the Fund's expenses in the Fund Summary in this Prospectus.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their family. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

Minimum Initial Investment	$1,000
Maximum Investment	None.
Initial Sales Charge	No. Entire purchase price is invested in shares of the Fund.
Deferred (CDSC) Sales Charge	No.
Distribution and/or Service (12b-1) Fees	0.05% annual fee.
Redemption Fees	No.

Investors pay no sales load to invest in Administration Class shares of the Fund. The price for Fund Shares is the NAV per share. Purchase requests received by the Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Time will earn dividend accrual for that purchase. All purchases that are made by check will be priced with the last valuation price and will begin earning dividends the following Business Day after the day the order is accepted. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) All purchase orders are subject to acceptance by the Fund. The Fund intends to be as fully invested as is practicable; therefore, investments must be made in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank).

The minimum initial investment in Administration Class shares of the Fund is $1,000 although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include, but are not limited to, accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Fund and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below). The Fund requires prior notification of subsequent investments in excess of $50,000,000. The Fund reserves the right to cease accepting investments at any time or to reject any investment order. In addition, the Fund may limit the amount of a purchase order received after 3:00 p.m. ET.

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How to Purchase Shares

By Mail:

An initial investment in the Fund must be preceded or accompanied by a completed, signed Institutional Account Application Form, sent to:
State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Fund and the Fund's agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Automatic Investment Plan. An Automatic Investment Plan is available for all operational State Street Funds that offer the Administration Class shares. Once an initial investment has been accepted, you may elect to make automatic subsequent investments of $100 or more on a periodic basis (i.e., monthly, quarterly, semi-annually, or annually) by authorizing the Fund to debit your bank checking or savings account through Automated Clearing House (ACH). Once this option has been established, you may call the State Street Funds to make additional automatic purchases, to change the amount of the existing automatic purchase, or to discontinue the service. The Fund reserves the right to cancel your Automatic Investment Plan if any correspondence sent by the Fund to your address of record is returned by the postal service or other delivery service as “undeliverable.” Ask your financial adviser or financial intermediary for details.

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Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after the Fund receives a redemption order in good form. If the Fund receives a redemption order in good form prior to 5:00 p.m. ET on a Business Day, shares are redeemed and the Fund typically sends payment for redeemed shares on that day, but no later than the next Business Day, if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund pays out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after 5:00 p.m. ET, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent), but no later than the following Business Day. The Fund may postpone and/or suspend redemption and payment beyond the foregoing time periods only as follows:

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;
c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Fund will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Fund calculates its NAV earlier than normal, the Fund reserves the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Fund may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and the Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of the Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Exchanges may be made within the same class (i.e. Administration Class shares for Administration Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected. Effective October 12, 2016, exchanges into or from any share of the State Street Institutional Liquid Reserves Fund will not be permitted.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Fund's Prospectus and the annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

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sentative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

The Internal Revenue Service (the “IRS”) permits a simplified method of accounting for gains and losses realized upon the disposition of shares of a regulated investment company that is a money market fund. Shareholders should see the SAI for further information.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund and net gains recognized on the redemption of Fund Shares.

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Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Fund has adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which the Fund may compensate SSGA FD (or others) for services in connection with the distribution of the Fund's shares and for services provided to Fund shareholders (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.05% of the Fund's net assets attributable to its Administration Class shares. Because these fees are paid out of the assets of the Fund attributable to its shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges. Long-term shareholders of the Fund may pay more in Rule 12b-1 fees than the economic equivalent of the maximum front-end sales charge permitted by the FINRA.

The Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of the Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

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If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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Financial Highlights

The financial highlight tables are intended to help you understand the Fund's Administration Class Shares financial performance since the inception date of the Administration Class shares. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Administration Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0026	0.0186	0.0150	0.0054
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—	0.0000(b)
Total from investment operations	0.0001	0.0026	0.0186	0.0150	0.0054
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0026)	(0.0186)	(0.0150)	(0.0054)
Net realized gains	—	—	—	—	0.0000(b)
Total distributions	(0.0001)	(0.0026)	(0.0186)	(0.0150)	(0.0054)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.01%	0.26%	1.88%	1.51%	0.54%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,230,490	$2,550,831	$1,672,762	$1,686,105	$1,909,670
Ratios to Average Net Assets:
Total expenses	0.37%	0.37%	0.37%	0.37%	0.37%
Net expenses	0.07%	0.23%	0.37%	0.37%	0.37%
Net investment income (loss)	0.01%	0.20%	1.87%	1.47%	0.50%

(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Fund's website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SALXXARIPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

Neuberger Berman Money Fund

A Private Label of the Institutional Class Shares of the

State Street Institutional U.S. Government Money Market Fund (SAHXX)

State Street Institutional Treasury Plus Money Market Fund (SAJXX)

Advised by SSGA Funds Management, Inc.,

a subsidiary of State Street Corporation

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund offers multiple classes of shares. This Prospectus covers only the Institutional Class.

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Fund Summaries	1
State Street Institutional U.S. Government Money Market Fund	1
State Street Institutional Treasury Plus Money Market Fund	7
Additional Information About Investment Objectives, Principal Strategies and Risks	12
Additional Information About Non-Principal Investment Strategies and Risks	18
Portfolio Holdings Disclosure	20
Management and Organization	21
Shareholder Information	23
Dividends, Distributions and Tax Considerations	28
Financial Intermediary Arrangements	30
Financial Highlights	31

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.10%
Total Annual Fund Operating Expenses¹	0.15%

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Repurchase Agreement Risk: Repurchase agreements may be viewed as loans made by the Fund, which are collateralized by the securities subject to repurchase. If the Fund's counterparty should default on its obligations and the Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, the Fund may realize a loss.

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q4, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Since Inception		Inception Date
Institutional Class		0.03%		1.04%		1/18/2018

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

To establish an account	$2,000.00
To add to an existing account	$100.00

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

Send a signed letter to:
Neuberger Berman Funds
State Street Global Advisors
P.O. Box 219189
Kansas City, MO 64121-9189

By Overnight:

Send a signed letter to:
Neuberger Berman Funds
c/o State Street Institutional Trust Funds
State Street Global Advisors
430 W 7^th Street Suite 219189
Kansas City, MO 64105-1407

By Telephone:

For wire transfer instructions, please call (800)-877-9700 between 9:00 a.m. and 5 p.m. Eastern time. Redemptions by telephone are permitted only if you previously have been authorized for these transactions.

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Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.10%
Total Annual Fund Operating Expenses¹	0.15%

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

Principal Investment Strategies

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Principal Risks

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.57% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Since Inception		Inception Date
Institutional		0.02%		0.97%		7/30/2018

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

To establish an account	$2,000.00
To add to an existing account	$100.00

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

Send a signed letter to:
Neuberger Berman Funds
State Street Global Advisors
P.O. Box 219189
Kansas City, MO 64121-9189

By Overnight:

Send a signed letter to:
Neuberger Berman Funds
c/o State Street Institutional Trust Funds
State Street Global Advisors
430 W 7^th Street Suite 219189
Kansas City, MO 64105-1407

By Telephone:

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Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the U.S. Government Fund and the Treasury Plus Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

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Additional Information About Risks

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Income Risk (principal risk for the U.S. Government Fund). A Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by a Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Fund may limit the Fund's ability to achieve its objective.

Low Short-Term Interest Rate Risk. During market conditions in which short-term interest rates are at low levels, a Fund's yield can be very low. During these conditions, it is possible that a Fund will generate an insufficient amount of income to pay its expenses, and that it will not be able to pay a daily dividend and may have a negative yield (i.e., it may lose money on an operating basis). It is possible that a Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income.

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governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU. Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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may have an incentive to invest in such master fund over a master fund sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a master fund sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a master fund sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so. A Fund will bear its pro rata portion of the expenses incurred by the master fund.

Mortgage-Related and Other Asset-Backed Securities Risk (principal risk for the U.S. Government Fund). Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically structured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk

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Reinvestment Risk (principal risk for the U.S. Government Fund). Income from a Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by a Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

Repurchase Agreement Risk. A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund, which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

U.S. Government Securities Risk (principal risk for the U.S. Government Fund). U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor supported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of a Fund's investments.

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U.S. Treasury Obligations Risk. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of a Fund's U.S. Treasury obligations to decline. The total public debt of the United States as a percent of gross domestic product grew rapidly after the financial crisis of 2008 and has remained at a historically high level. Although high debt levels do not necessarily indicate or cause economic problems, they may create certain systemic risks if sound debt management practices are not implemented. A high national debt level may increase market pressures to meet government funding needs, which may drive debt cost higher and cause a country to sell additional debt, thereby increasing refinancing risk. A high national debt also raises concerns that a government will not be able to make principal or interest payments when they are due. In the worst case, unsustainable debt levels can cause a decline in the value of the dollar (which may lead to inflation), and can prevent the U.S. government from implementing effective counter-cyclical fiscal policy in economic downturns. On August 5, 2011, Standard & Poor's Ratings Services downgraded U.S. Treasury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

Additional Information About Non-Principal Investment Strategies and Risks

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clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by a Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Funds) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Funds, the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

A Fund can withdraw its investment in a Portfolio if, at any time, the Fund's Board of Trustees (the “Board” and each member thereof, a “Trustee”) determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives of the corresponding Portfolio changed so that they were inconsistent with the objectives of the Fund. If a Fund withdraws its investment from a Portfolio, the Fund may invest all of its assets in another mutual fund that has the same investment objective as the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

SSGA FM serves as the investment adviser to each Fund and corresponding Portfolio and, subject to the oversight of the Board, is responsible for the investment management of each Fund. The Adviser provides an investment management program for each Fund and manages the investment of each Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the SEC under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.05% for Treasury Plus Portfolio and 0.05% for U.S. Government Portfolio.

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A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized oneday yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

The “Servicing Agent”

Neuberger Berman Investment Advisers LLC (“Neuberger Berman”) serves as the servicing agent for shareholders of mutual funds distributed and advised by Neuberger Berman (a “Neuberger Berman Fund”) that are also shareholders of a Fund.

Additional Information

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Shareholder Information

Note: This prospectus is intended to relate principally to purchases of shares through Neuberger Berman. Information appearing below assumes that shares are purchased and redeemed through Neuberger Berman and is based on information previously provided by Neuberger Berman to the Funds.

Determination of Net Asset Value

Each of the Funds determines its NAV per share once each day on which the New York Stock Exchange (the “NYSE”), the Federal Reserve banks and State Street are open for business (a “Business Day”) at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event the Fund will determine its NAV at the earlier closing time (the time when the Fund determines its NAV per share is referred to herein as the “Valuation Time”). Pricing does not occur on NYSE holidays.

The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. The Funds reserve the right to accept orders to purchase or redeem shares, or to continue to accept such orders following the close of the NYSE, on any day that is not a Business Day or any day on which the NYSE closes early, provided the Federal Reserve remains open. The Funds also may establish special hours on those days to determine each Fund's NAV. In the event that the Funds invoke the right to accept orders to purchase or redeem shares on any day that is not a Business Day or adopt special hours of operation, the Funds will post advance notice of these events at: www.ssga.com/cash.

Each Fund seeks to maintain a $1.00 per share NAV and, accordingly, uses the amortized cost valuation method, in compliance with the risk limiting conditions of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”), to value its portfolio instruments. The amortized cost valuation method initially prices an instrument at its cost and thereafter assumes a constant amortization to maturity of any discount or premium, regardless of the impact of fluctuating interest rates on the market value of the instrument.

Investing in State Street Institutional Investment Trust Shares

Requests for transactions in the State Street Funds will be processed when they are received in “good order.” “Good order” means that the request is in an accurate and complete form, and all applicable documents have been received in such accurate and complete form (including, typically, a signed application and medallion-guaranteed documents), and, for a purchase request, the check or wired funds have cleared.

Purchasing Shares

Investors pay no sales load to invest in shares of the Funds. The price for Fund Shares is the NAV per share. Purchase requests received by a Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of

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a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Time will earn dividend accrual for that purchase.

All purchases that are made by check will begin earning dividends the following Business Day after the day the order is accepted.(If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) All purchase orders are subject to acceptance by the Funds. The Funds intend to be as fully invested as is practicable; therefore, investments must be made in Federal Funds (i.e., monies credited to the account of the Funds' custodian bank by a Federal Reserve Bank).

Neuberger Berman is responsible for transmitting your purchase request and funds in good form and in a timely manner to the applicable Fund(s). A Fund will not be responsible for delays by Neuberger Berman in transmitting your purchase request, including timely transfer of payment, to the Fund.

The Funds reserve the right to cease accepting investments at any time or to reject any investment order. In addition, the Funds may limit the amount of a purchase order received after 3:00 p.m. ET.

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How to Purchase Shares

By Mail:

An initial investment in the Funds must be preceded or accompanied by a completed, signed Neuberger Berman Fund Application Form, sent to:

Neuberger Berman Funds
c/o State Street Institutional Trust Funds
State Street Global Advisors
430 W 7^th Street Suite 219189
Kansas City, MO 64105-1407

Your first investment must be at least $2,000. Additional investments can be as little as $100. All checks must be made out to “Neuberger Berman Funds”. Neuberger Berman will not accept checks made out to you or other parties and signed over to it. Neuberger Berman cannot accept cash, money orders, starter checks, cashier's checks, traveler's checks or other cash equivalents. You will be responsible for any losses or fees resulting from a bad check. If necessary, Neuberger Berman may effect sales of Fund shares belonging to you in order to cover these losses.

By Telephone:

An initial investment in the Funds must be preceded or accompanied by a completed, signed Neuberger Berman Fund Application Form. Neuberger Berman does not accept phone orders for a first investment. To add shares to an existing account using FUNDfone^®», call (800) 335-9366.

Additional shares will be purchased when your order is accepted by the Funds. Additional investments must be for at least $100.

For your initial investment, send the original, signed Neuberger Berman Account Application Form to the address above.

Wire Instructions:

Before wiring any money, call (800) 877-9700 for an order confirmation. Please have your financial institution send your wire to Neuberger Berman's account at State Street Bank and Trust Company and include your name, the Fund name, your account number and other information as requested.

State Street Bank/Boston
ABA# 011-000028
Attn: NB Deposit Account
DDA#9904-199-8

By Internet:

You may place an order with Neuberger Berman to purchase shares for your account by placing an order online at www.nb.com.

You will not be able to redeem shares from the account until the original Application has been received. The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

In accordance with certain federal regulations, Neuberger Berman is required to obtain, verify and record information that identifies each entity that applies to open an account. For this reason, when you open (or change ownership of) an account, Neuberger Berman will request certain information, including your name, residential/business address, date of birth (for individuals) and taxpayer identification number or other government identification number and other information that will allow us to identify you which will be used to verify your identity. Neuberger Berman may also request to review other identification documents such as driver license, passport or documents showing the existence of the business entity. If you do not provide sufficient information to verify your identity, Neuberger Berman will not open an account for you. As required by law, Neuberger Berman may employ various procedures, such as comparing your information to fraud databases or requesting additional information and documentation from you, to ensure that the information supplied by you is correct. Neuberger Berman reserves the right to reject any purchase for any reason, including failure to provide the Trust with information necessary to confirm your identity as required by law.

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Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form to Neuberger Berman.

For the Treasury Plus Fund

If Neuberger Berman receives a redemption order in good form prior to 4:30 p.m. Eastern Time on a Business Day, shares are redeemed and Neuberger Berman typically expects to pay out redemption proceeds on that day, but no later than the next Business Day, if redemption proceeds are sent by wire or ACH. No dividends will be paid on shares that are redeemed and wired the same day. If redemption proceeds are sent by check, Neuberger Berman typically expects to pay out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after 4:30 p.m. Eastern Time, Neuberger Berman typically expects to pay out the redemption proceeds for the shareholder the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). The Treasury Plus Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

For the U.S. Government Fund

If Neuberger Berman receives a redemption order in good form prior to 4:30 p.m. Eastern Time on a Business Day, shares are redeemed and Neuberger Berman typically expects to pay out redemption proceeds on that day, but no later than the next Business Day, if redemption proceeds are sent by wire or ACH. No dividends will be paid on shares that are redeemed and wired the same day. If redemption proceeds are sent by check, Neuberger Berman typically expects to pay out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after 4:30 p.m. Eastern Time, Neuberger Berman typically expects to pay out the redemption proceeds for the shareholder the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). The U.S. Government Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

For All Funds

Each Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. The right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed in accordance with Section 22(e) of the 1940 Act and the rules thereunder, including during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or if an emergency exists as a result of which disposal by the Fund of securities owned by it is not reasonably practicable or it is not reasonably practicable for the Fund fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of shareholders of the Fund. Although each Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

When selling shares in an account that you do not intend to close, remember to leave at least $2,000 worth of shares in the account. Otherwise, Neuberger Berman has the right to request that you bring the balance back up to the minimum level. If you have not done so within 60 days, Neuberger Berman may close your account and redeem the proceeds. Neuberger Berman is responsible for transmitting your redemption request in good form and in a timely manner to the applicable Fund(s). A Fund will not be responsible for delays by Neuberger Berman in transmitting your redemption request to the Fund.

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How to Redeem Shares


By Mail:	Send a signed letter to: Neuberger Berman Funds c/o State Street Bank & Trust Co. 430 West 7th Street Suite 219189 Kansas City, MO 64105-1407
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Telephone:	Please call Neuberger Berman at (800) 877-9700 between the hours of 9:00 a.m. and 5:00 p.m. ET.
You must provide the following information: ➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ the dollar amount, percentage or number of shares being redeemed; and ➣ any other instructions. To place an order using FUNDfone^®», call (800) 335-9366.
By Internet:	You may instruct Neuberger Berman to redeem shares by placing an order online at www.nb.com.

On any day that the Funds calculate NAV earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. You may need a Medallion signature guarantee when you sell shares of a Fund. A Medallion signature guarantee is a guarantee that your signature is authentic. Most banks, brokers and other financial institutions can provide you with one. Some may charge a fee; others may not, particularly if you are a customer of theirs.

Medallion signature guarantees are required for a variety of transactions including requests for changes to your account or to the instructions for distribution of proceeds. Neuberger Berman reserves the right to require a Medallion signature guarantee on any transaction at our discretion.

A notarized signature from a notary public is not a Medallion signature guarantee.

Exchanging Shares. You can move an investment from a Fund to a comparable class of another Neuberger Berman Fund in the Fund family through an exchange of shares, or by electing to use your cash distributions from a Fund to purchase shares of the other Fund. There are three things to remember when making an exchange:

•	both accounts must have the same registration;
•	you will need to observe the minimum account balance requirements for the fund accounts involved; and
•	because an exchange is treated as a sale for tax purposes, consider any tax consequences before placing your order.

Privileges and Services. You have access to a range of Neuberger Berman services to make investing easier:

Systematic Withdrawals. This plan lets you arrange withdrawals of at least $100 from a Fund on a periodic schedule. You can also set up payments to distribute the full value of an account over a given time.

Electronic Bank Transfers. When you sell Fund shares, you can have the money sent to your bank account electronically rather than mailed to you as a check. Please note that your bank must be a member of the Automated Clearing House, or ACH, system.

Internet Access. At www.nb.com, you can initiate transactions, check your account and access a wealth of information.

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FUNDfone^®. Get up-to-date performance and account information through our 24-hour automated service by calling (800) 335-9366. If you already have a Neuberger Berman fund account, you can place orders to buy, sell or exchange fund shares.

Checkwriting. If you would like to write checks against your Institutional U.S. Government Money Market Fund account, please call (800) 877-9700. Withdrawals must be for at least $250.

About Mail Transactions. If you choose to purchase, exchange or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 West 7th Street, Suite 219189 in Kansas City, MO 64105. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Other Policies. Under certain circumstances, Neuberger Berman reserves the right to:

•	reject any exchange or purchase order;
•	suspend or reject any future purchase order from any investor who does not provide payment to settle a purchase order;
•	change, suspend or revoke the exchange privilege; and
•	suspend the telephone order privilege.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund).

Excessive Trading

Because the Funds are money market funds, the Board has not adopted policies and procedures with respect to frequent purchases and redemptions of Fund shares by Fund shareholders. Nonetheless, the Funds may take any reasonable action that they deem necessary or appropriate to prevent excessive trading in Fund shares without providing prior notification to the account holder. Such action may include rejecting any purchase, in whole or part, including, without limitation, by a person whose trading activity in Fund shares may be deemed harmful to the Fund. While the Funds attempt to discourage such excessive trading, there can be no guarantee that they will be able to identify investors who are engaging in excessive trading or limit their trading practices. Additionally, frequent trades of small amounts may not be detected. The Funds recognize that they may not always be able to detect or prevent excessive trading or other activity that may disadvantage the Funds or their shareholders.

Dividends, Distributions and Tax Considerations

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elected to receive distributions by check, and the postal or other delivery service is unable to deliver the checks because of an incorrect mailing address, or if a distribution check remains uncashed for six months, the uncashed distribution and all future distributions will be reinvested at the then-current NAV of the Fund.

For U.S. federal income tax purposes, distributions of investment income are generally taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Portfolio or Fund owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Any net short-term gains the Fund distributes will be taxable to you as ordinary income. The Funds generally do not expect to make distributions that are eligible for taxation as long-term capital gains. Distributions are taxable to you even if they are paid from income or gains earned by a Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of a Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Fund's shares, and, in general, as capital gain thereafter.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

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Financial Intermediary Arrangements

Payments to Financial Intermediaries

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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Financial Highlights

The financial highlight tables are intended to help you understand each Fund's Institutional Class Shares financial performance since inception of Institutional Class shares. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in each Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with each Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of each Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 1/18/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0037	0.0207	0.0170
Net realized gain (loss)	—	0.0000(b)	0.0000(b)	—
Total from investment operations	0.0001	0.0037	0.0207	0.0170
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0037)	(0.0207)	(0.0170)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.03%	0.37%	2.09%	1.67%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$1,588,396	$1,349,398	$950,202	$639,733
Ratios to Average Net Assets:
Total expenses	0.15%	0.15%	0.15%	0.15%(d)
Net expenses	0.04%	0.14%	0.15%	0.15%(d)
Net investment income (loss)	0.03%	0.42%	1.95%	1.71%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Institutional Class (a)
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	For the Period 7/31/18*- 12/31/18
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001	0.0037	0.0207	0.0085
Net realized gain (loss)	—	—	(0.0000)(b)	—
Total from investment operations	0.0001	0.0037	0.0207	0.0085
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0037)	(0.0207)	(0.0085)
Total distributions	(0.0001)	(0.0037)	(0.0207)	(0.0085)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.02%	0.37%	2.09%	0.85%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$278,027	$90,569	$468,721	$94,554
Ratios to Average Net Assets:
Total expenses	0.15%	0.15%	0.15%	0.15%(d)
Net expenses	0.06%	0.15%	0.15%	0.15%(d)
Net investment income (loss)	0.02%	0.34%	2.09%	2.04%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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For more information about the Funds:

The SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the investments is available in the most recent annual and semi-annual reports to shareholders. The SAI is available, without charge, upon request. The annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

00274683

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Treasury Obligations Money Market Fund (TAQXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the Fund offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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Fund Summary	1
State Street Treasury Obligations Money Market Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	7
Additional Information About Non-Principal Investment Strategies and Risks	11
Portfolio Holdings Disclosure	13
Management and Organization	14
Shareholder Information	16
Dividends, Distributions and Tax Considerations	21
Financial Intermediary Arrangements	22
Financial Highlights	25

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State Street Treasury Obligations Money Market Fund

Investment Objective

The investment objective of State Street Treasury Obligations Money Market Fund (the “Treasury Obligations Fund” or sometimes referred to in context as the “Fund”) is to seek a high level of current income consistent with preserving principal and liquidity and the maintenance of a stable $1.00 per share net asset value (“NAV”).

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Treasury Obligations Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. The expenses shown in the table and the Example reflect the expenses of the Fund and the Fund's proportionate share of the expenses of the State Street Treasury Plus Money Market Portfolio (the “Treasury Plus Portfolio” or sometimes referred to in context as the “Portfolio”).

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses	0.07%
Total Annual Fund Operating Expenses	0.12%
Less Fee Waivers and/or Expense Reimbursements¹	(0.02%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements¹	0.10%

The Fund's investment adviser, SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”), is contractually obligated until April 30, 2023 (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, and extraordinary expenses) exceed 0.10% of average daily net assets on an annual basis. This waiver and/or reimbursement may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees. The Adviser and its affiliates, may voluntarily reduce all or a portion of their fees and/or reimburse expenses of the Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”), or a yield below a specified level, which may vary from time to time in the Adviser's sole discretion. The Fund has agreed, subject to certain limitations, to reimburse the Adviser and its affiliates for the full dollar amount of any Voluntary Reduction incurred beginning on May 1, 2020. During the fiscal year ended December 31, 2021, the Adviser and its affiliates waived fees and/or reimbursed expenses under the Voluntary Reduction. Each of the Adviser and its affiliates may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund. Any future reimbursement by the Fund of the Voluntary Reduction would increase the Fund's expenses and may reduce the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield.

Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell or hold all of your Fund Shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The calculation of costs for the one-year periods takes into account the effect of the current contractual fee waivers and/or reimbursements. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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1 year		3 years		5 years		10 years
$10		$37		$66		$152

Principal Investment Strategies

The Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term securities (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Treasury Plus Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Treasury Plus Portfolio, and it participates in the investment returns achieved by the Treasury Plus Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Treasury Plus Portfolio.

Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Obligations Fund by illustrating the variability of the Fund's returns from year-to-year. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.59% (Q2, 2019)
Lowest Quarterly Return: 0.01% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Since Inception		Inception Date
State Street Treasury Obligations Money Market Fund		0.02%		1.09%		10/5/2017

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

To establish an account	$1,000,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

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Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

Investment Objective

The Board of Trustees (the “Board” and each member thereof, a “Trustee”) may change the Fund's investment objective without shareholder approval.

Principal Investment Strategies

The Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term securities (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund seeks to achieve its investment objective by investing substantially all of its investable assets in the Treasury Plus Portfolio, which has substantially identical investment policies to the Fund. When the Fund invests in this “master-feeder” structure, the Fund's only investments are shares of the Treasury Plus Portfolio, and it participates in the investment returns achieved by the Treasury Plus Portfolio. Descriptions in this section of the investment activities of the “Fund” also generally describe the expected investment activities of the Treasury Plus Portfolio.

Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

The credit rating assigned to any particular investment does not necessarily reflect the issuer's current financial condition and does not reflect an assessment of an investment's volatility or liquidity. Securities rated in the lowest category of investment-grade are considered to have speculative characteristics. If a security held by the Fund loses its rating or its rating is downgraded, the Fund may nonetheless continue to hold the security in the discretion of the Adviser. In the case of asset-backed or mortgage-related securities, changes in the actual or perceived ability of the obligors on the underlying assets or mortgages to make payments of interest and/or principal may affect the values of those securities.

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Debt Securities Risk. The values of debt securities may increase or decrease as a result of the following: market fluctuations, changes in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. The current low interest rate environment heightens the risks associated with rising interest rates. During periods when interest rates are at low levels, the Fund's yield can be low, and the Fund may have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Low Short-Term Interest Rate Risk. During market conditions in which short-term interest rates are at low levels, the Fund's yield can be very low. During these conditions, it is possible that the Fund will generate an insufficient amount of income to pay its expenses, and that it will not be able to pay a daily dividend and may have a negative yield (i.e., it may lose money on an operating basis). It is possible that the Fund would, during these conditions, maintain a substantial portion of its assets in cash, on which it may earn little, if any, income.

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world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of the Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of the Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by the Fund. To the extent the Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

Rapid Changes in Interest Rates. The values of instruments held by the Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause the Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses could impair the Fund's ability to maintain a stable share price of $1.00.

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by the securities subject to repurchase. The Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If the Fund's counterparty should default on its obligations and the Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, the Fund may realize a loss.

Variable and Floating Rate Securities Risk. Variable or floating rate securities are debt securities with variable or floating interest rates payments. Variable or floating rate securities bear rates of interest that are adjusted periodically according to formulae intended generally to reflect market rates of interest and allow the Fund to participate (determined in accordance with the terms of the securities) in increases in interest rates through upward adjustments of the coupon rates on the securities. However, during periods of increasing interest rates, changes in the coupon rates may lag behind the changes in market rates or may have limits on the maximum increases in coupon rates. Alternatively, during periods of declining interest rates, the coupon rates on such securities will typically readjust downward resulting in a lower yield. The Fund may also invest in variable or floating rate equity securities, whose dividend payments vary based on changes in market rates of interest or other factors.

Additional Information About Non-Principal Investment Strategies and Risks

The investments described below reflect the Fund's and the Treasury Plus Portfolio's current practices. In addition to the principal risks described above, other risks are described in some of the descriptions of the investments below:

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erally or as favorable as the rates the Adviser or its affiliates make available to other clients. Because of its financial interest, the Adviser will have an incentive to enter into transactions or arrangements on behalf of the Fund with itself or its affiliates in circumstances where it might not have done so in the absence of that interest, provided that the Adviser will comply with applicable regulatory requirements.

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Fund) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Fund, the Portfolio and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, the Fund, the Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect the Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect the Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject the Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

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have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Various financial industry groups have been planning for the transition away from LIBOR and markets are developing in response to these new rates, but questions around the liquidity of the new rates and how to appropriately adjust these rates to eliminate any economic value transfer at the time of transition remain a significant concern. The transition away from and eventual elimination of LIBOR may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include “fall back” provisions addressing the transition from LIBOR. Uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by the Fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Fund.

Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

The Fund invests as part of a “master/feeder” structure. The Fund currently seeks to achieve its investment objective by investing substantially all of its investable assets in the Treasury Plus Portfolio, a separate mutual fund, that has substantially identical investment objective, investment policies, and risks as the Fund. All discussions about the Fund's investment objective, policies and risks should be understood to refer also to the investment objectives, policies and risks of the Treasury Plus Portfolio.

The Fund can withdraw its investment in the Portfolio if, at any time, the Board determines that it would be in the best interests of the Fund's shareholders, or if the investment objectives of the Treasury Plus Portfolio changed so that they were inconsistent with the objectives of the Fund. If the Fund withdraws its investment from the Portfolio, the Fund may invest all of its assets in another mutual fund that has the same investment objective as the Fund, the Adviser may directly manage the Fund's assets, or the Board may take such other action it deems appropriate and in the best interests of shareholders of the Fund, which may include liquidation of the Fund.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund and the Treasury Plus Portfolio and, subject to the oversight of the Board, is responsible for the investment management of the Fund. The Adviser provides an investment management program for the Fund and manages the investment of the Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the SEC under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

The Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in the Treasury Plus Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from the Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the Treasury Plus Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolio's investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.05% for Treasury Plus Portfolio.

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund, is contractually obligated until April 30, 2023 (i) to waive up to the full amount of the advisory fee payable by the Fund and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, and extraordinary expenses) exceed 0.10% of average daily net assets on an annual basis (the “Total Annual Fund Operating Expense Waiver”). The Total Annual Fund Operating Expense Waiver may not be terminated prior to April 30, 2023 except with approval of the Board.

Voluntary Expense Waiver. Additionally, the Adviser has voluntarily agreed to waive its advisory fee and/or to reimburse the Fund for expenses to the extent that the Fund's total annual operating expenses exceed 0.08% of average daily net assets on an annual basis (the “Voluntary Expense Waiver”). The Adviser may discontinue the voluntary fee waiver and/or expense limitation arrangement at any time, in its sole discretion.

In addition to any contractual expense limitation for the Fund, which is described in the Fund Summary, each of the Adviser and State Street Global Advisors Funds Distributors, LLC (each a “Service Provider”) also may voluntarily reduce all or a portion of its fees and/or reimburse expenses for the Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”). The Adviser may, in its sole discretion, implement the Voluntary Reduction for some Funds, or some share classes of a Fund, and not others. The amount of

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any Voluntary Reduction may differ between Funds and share classes in the Adviser's sole discretion. The business objectives of the Adviser and its affiliates and their broader relationships with certain Fund shareholders, Financial Intermediaries or distribution channels could give the Adviser an incentive to implement the Voluntary Reduction for some Funds or share classes and not others, or to implement it to a greater degree for some Funds or share classes than others. Under an agreement with the Service Providers relating to the Voluntary Reduction, A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class, the Fund and the Portfolio have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund.

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement is provided in the Fund's Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of the Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. The Fund currently pays the Adviser an administrative fee at the annual rate of 0.05%. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Fund for a fee that is paid by the Adviser. State Street also serves as custodian of the Fund for a separate fee that is paid by the Fund. SSGA FM serves as administrator of the Portfolio and State Street serves as sub-administrator and custodian of the Portfolio.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

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Shareholder Information

Determination of Net Asset Value

The Fund determines its NAV per share once each day on which the NYSE, the Federal Reserve banks and State Street are open for business (a “Business Day”) at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event the Fund will determine its NAV at the earlier closing time (the time when the Fund determines its NAV per share is referred to herein as the “Valuation Time”). Pricing does not occur on NYSE holidays.

The Federal Reserve is closed on certain holidays on which the NYSE is open. These holidays are Columbus Day and Veterans Day. On these holidays, you will not be able to purchase shares by wiring Federal Funds because Federal Funds wiring does not occur on days when the Federal Reserve is closed. The Fund reserves the right to accept orders to purchase or redeem shares, or to continue to accept such orders following the close of the NYSE, on any day that is not a Business Day or any day on which the NYSE closes early, provided the Federal Reserve remains open. As noted in this Prospectus, the Fund may invest in securities listed on foreign exchanges, or otherwise traded in a foreign market, and those securities may trade on weekends or other days when the Fund does not price its shares. Consequently, the NAV of the Fund's shares may change on days when shareholders are not able to purchase or redeem the Fund's shares. The Fund also may establish special hours on those days to determine the Fund's NAV. In the event that the Fund invoke the right to accept orders to purchase or redeem shares on any day that is not a Business Day or adopt special hours of operation, the Fund will post advance notice of these events at: www.ssga.com/cash.

Investing in State Street Institutional Investment Trust Shares

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Purchasing Shares

Investors pay no sales load to invest in the Fund Shares. The price for Fund Shares is the NAV per share. Purchase requests received by the Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed application and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Times will earn dividend accrual for that purchase.

All purchases that are made by check will begin earning dividends the following Business Day after the day the order is accepted. (If you purchase shares by check, your order will not be in good form until the Transfer Agent receives federal funds for the check.) All purchase orders are subject to acceptance by the Fund. The Fund intends to be as fully invested as is practicable; therefore, investments must be made in Federal Funds (i.e., monies credited to the account of the Fund's custodian bank by a Federal Reserve Bank).

The minimum initial investment in the Fund is $1 billion, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include, but are not limited to, accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Fund and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below).The Fund requires prior notification of subsequent investments in excess of $50 million. The Fund reserves the right to cease accepting investments at any time or to reject any investment order. The Fund may limit the amount of a purchase order received after 3:00 p.m. ET.

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How to Purchase Shares

By Mail:

An initial investment in the Fund must be preceded or accompanied by a completed, signed Institutional Account Application Form, sent to:
State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Account Number
Account Registration

The Fund and the Fund's agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after the Fund receives a redemption order in good form.

If the Fund receives a redemption order in good form prior to 5:00 p.m. ET on a Business Day, the Fund typically expects to pay out redemption proceeds on that day, but no later than next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. If a redemption order is placed after 5:00 p.m. ET, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). The Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

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The Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. The right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed in accordance with Section 22(e) of the 1940 Act and the rules thereunder, including during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or if an emergency exists as a result of which disposal by the Fund of securities owned by it is not reasonably practicable or it is not reasonably practicable for the Fund fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of shareholders of the Fund. Although the Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

The Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Fund reserves the right to modify minimum account requirements at any time with or without prior notice. The Fund also reserves the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Fund will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Fund calculates its NAV earlier than normal, the Fund reserves the right to adjust the times noted above for purchasing and redeeming shares.

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Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Fund reserves the right to waive medallion guarantee requirements, require a medallion guarantee under other circumstances or reject or delay redemption if the medallion guarantee is not in good form. Medallion guarantees may be provided by an eligible financial institution such as a commercial bank, a FINRA member firm such as a stock broker, a savings association or a national securities exchange. A notary public cannot provide a medallion guarantee. The Fund reserves the right to reject a medallion guarantee if it is not provided by a STAMP Medallion guarantor.

The Fund may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and the Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

Currently, exchanging shares from/to this Fund to any other State Street Fund is not permitted.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Fund's Prospectus and the annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

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Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

The Fund invests substantially all of its investible assets in a Portfolio that is treated as a partnership for U.S. federal income tax purposes. The nature and character of the Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and the Fund will be allocated its share of the Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of the Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of the Fund will be to the Fund's allocable share of the assets of the Portfolio.

For U.S. federal income tax purposes, distributions of investment income are generally taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Portfolio or Fund owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. The Fund generally does not expect to make distributions that are eligible for taxation as long-term capital gains. Distributions are taxable to you even if they are paid from income or gains earned by the Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of a Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the Fund's shares, and, in general, as capital gain thereafter.

The Fund's income from or proceeds of investments in non-U.S. assets may be subject to non-U.S. withholding and other taxes. This will decrease the Fund's return on securities subject to such taxes. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes. Although such taxes will reduce the Fund's taxable income, sharehold-

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ers generally will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Fund.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund and net gains recognized on the redemption of Fund Shares.

Financial Intermediary Arrangements

Payments to Financial Intermediaries

The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

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SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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Financial Highlights

The financial highlight tables are intended to help you understand the Fund's financial performance since the Treasury Obligations Money Market Fund's inception. Certain information reflects the performance results for a single Fund Share. The total returns in the table represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with the Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request. Any references to Notes in these financial highlight tables refer to the “Notes to Financial Statements” section of the Fund's financial statements, and the financial information included in these tables should be read in conjunction with the financial statements incorporated by reference in the SAI.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET TREASURY OBLIGATIONS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period


	Year Ended 12/31/21(a)	Year Ended 12/31/20(a)	Year Ended 12/31/19(a)	Year Ended 12/31/18(a)	For the Period 10/05/17^* - 12/31/17(a)
Net asset value, beginning of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0002	0.0045	0.0213	0.0178	0.0025
Net realized and unrealized gain (loss)	(0.0001)	(0.0001)	(0.0000)(b)	—	—
Total from investment operations	0.0001	0.0044	0.0213	0.0178	0.0025
Distributions to shareholders from:
Net investment income	(0.0001)	(0.0044)	(0.0213)	(0.0178)	(0.0025)
Total distributions	(0.0001)	(0.0044)	(0.0213)	(0.0178)	(0.0025)
Net asset value, end of period	$1.0000	$1.0000	$1.0000	$1.0000	$1.0000
Total return (c)	0.02%	0.44%	2.16%	1.79%	0.25%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$3,755,757	$2,753,990	$4,220,578	$3,620,569	$2,926,362
Ratios to average net assets:
Total expenses	0.12%	0.12%	0.12%	0.13%	0.16%(d)
Net expenses	0.05%	0.08%	0.08%	0.08%	0.08%(d)
Net investment income (loss)	0.02%	0.45%	2.13%	1.77%	1.08%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

The Fund's SAI includes additional information about the Fund and is incorporated by reference into this document. Additional information about the Fund's investments is available in the Fund's most recent annual and semi-annual reports to shareholders. The Fund's SAI is available, without charge, upon request. The Fund's annual and semi-annual reports are available, without charge, upon request. Shareholders in the Fund may make inquiries to the Fund to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. The Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

TAQXXSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street Institutional Treasury Money Market Fund: Select Class (TYSXX)

State Street Institutional Treasury Plus Money Market Fund: Select Class (TPSXX)

State Street Institutional U.S. Government Money Market Fund: Select Class (GVSXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Select Class Shares of the Funds.

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Fund Summaries	1
State Street Institutional Treasury Money Market Fund	1
State Street Institutional Treasury Plus Money Market Fund	6
State Street Institutional U.S. Government Money Market Fund	11
Additional Information About Investment Objectives, Principal Strategies and Risks	17
Additional Information About Non-Principal Investment Strategies and Risks	24
Portfolio Holdings Disclosure	26
Management and Organization	27
Shareholder Information	29
Dividends, Distributions and Tax Considerations	34
Financial Highlights	37

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State Street Institutional Treasury Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.07%
Total Annual Fund Operating Expenses	0.12%
Less Fee Waivers and/or Expense Reimbursements²	(0.04%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements²	0.08%

¹	Other Expenses are based on estimates for the current fiscal year.

SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”) is contractually obligated until April 30, 2023 to reimburse the Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of interest, brokerage commissions, taxes, extraordinary expenses, deferred organizational expenses or acquired fund fees and expenses) of the Select Class shares of the Fund exceed 0.08% of average daily net assets on an annual basis. This reimbursement arrangement for Select Class shares of the Fund may not be terminated prior to April 30, 2023 except with approval of the Fund's Board of Trustees. The Adviser and its affiliates, may voluntarily reduce all or a portion of their fees and/or reimburse expenses of the Fund or a share class to the extent necessary tomaintain a certain minimum net yield, which may vary from time to time and from share class to share class within the Fund, in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”), or a yield below a specified level, which may vary from time to time in the Adviser's sole discretion. The Fund has agreed, subject to certain limitations, to reimburse the Adviser and its affiliates for the full dollar amount of any Voluntary Reduction incurred beginning on May 1, 2020. During the fiscal year ended December 31, 2021, the Adviser and its affiliates waived fees and/or reimbursed expenses under the Voluntary Reduction. Each of the Adviser and its affiliates may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from the Fund. Any future reimbursement by the Fund of the Voluntary Reduction would increase the Fund's expenses and may reduce the Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that the Fund will be able to avoid a negative yield.

Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell or hold all of your Fund Shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The calculation of costs for the one-year period takes into account the effect of any current contractual fee waivers and/or reimbursements, and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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1 year		3 years		5 years		10 years
$8		$35		$64		$150

Principal Investment Strategies

Principal Risks

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liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. Performance history will be available for the Select Class shares of the Fund after they have been in operation for one calendar year. Returns of Select Class shares could have been similar to the returns shown for Premier Class shares because the shares are invested in the same portfolio of securities. Returns would differ only to the extent that Select Class shares do not have the same expenses as Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.57% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.01%		1.00%		0.52%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Eligible investors of the Select Class shares of the Fund are limited to institutional entities that hold Fund Shares directly with the Fund. Select Class shares of the Fund generally are not offered to shareholders through a broker, bank or other financial intermediary (“Financial Intermediary”).

Purchase Minimums

Select Class
To establish an account	$750,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

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Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Select Class shares of the Fund generally are not offered for purchase through Financial Intermediaries.

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.07%
Total Annual Fund Operating Expenses	0.12%
Less Fee Waivers and/or Expense Reimbursements²	(0.04%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements²	0.08%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell or hold all of your Fund Shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The calculation of costs for the one-year period takes into account the effect of any current contractual fee waivers and/or reimbursements, and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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1 year		3 years		5 years		10 years
$8		$35		$64		$150

Principal Investment Strategies

Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. Performance history will be available for the Select Class shares of the Fund after they have been in operation for one calendar year. Returns of Select Class shares could have been similar to the returns shown for Premier Class shares because the shares are invested in the same portfolio of securities. Returns would differ only to the extent that Select Class shares do not have the same expenses as Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.02%		1.01%		0.52%		10/24/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Select Class
To establish an account	$750,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Select Class shares of the Fund generally are not offered for purchase through Financial Intermediaries.

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.07%
Total Annual Fund Operating Expenses	0.12%
Less Fee Waivers and/or Expense Reimbursements²	(0.04%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements²	0.08%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

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into account the effect of any current contractual fee waivers and/or reimbursements, and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 year		3 years		5 years		10 years
$8		$35		$64		$150

Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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have a negative yield (i.e., it may lose money on an operating basis). If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. Performance history will be available for the Select Class shares of the Fund after they have been in operation for one calendar year. Returns of Select Class shares could have been similar to the returns shown for Premier Class shares because the shares are invested in the same portfolio of securities. Returns would differ only to the extent that Select Class shares do not have the same expenses as Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2013)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.03%		1.02%		0.54%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Select Class
To establish an account	$750,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

Select Class shares of the Fund generally are not offered for purchase through Financial Intermediaries.

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the Treasury Fund, the Treasury Plus Fund and the U.S. Government Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

Treasury Fund

Principal Investment Strategies

The Treasury Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government). The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

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U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

Counterparty Risk (principal risk for the U.S. Government Fund and Treasury Plus Fund). A Fund will be subject to credit risk with respect to the counterparties with which a Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, a Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Credit Risk (principal risk for the U.S. Government Fund and Treasury Plus Fund). Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived

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decline in creditworthiness of an issuer of a fixed-income security held by a Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

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accelerate the realization of taxable income and/or gains to investors, or a Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case a Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. A Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Market Disruption and Geopolitical Risk. A Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of a Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU. Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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Repurchase Agreement Risk (principal risk for the U.S. Government Fund and Treasury Plus Fund). A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund, which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

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the U.S. government agencies or instrumentalities in which the Fund invests may have a significant impact on a Fund's performance. Events that would adversely affect the market prices of securities issued or guaranteed by one government agency or instrumentality may adversely affect the market price of securities issued or guaranteed by other government agencies or instrumentalities.

U.S. Treasury Obligations Risk (principal risk for the Treasury Fund, Treasury Plus Fund and U.S. Government Fund). U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of a Fund's U.S. Treasury obligations to decline. The total public debt of the United States as a percent of gross domestic product grew rapidly after the financial crisis of 2008 and has remained at a historically high level. Although high debt levels do not necessarily indicate or cause economic problems, they may create certain systemic risks if sound debt management practices are not implemented. A high national debt level may increase market pressures to meet government funding needs, which may drive debt cost higher and cause a country to sell additional debt, thereby increasing refinancing risk. A high national debt also raises concerns that a government will not be able to make principal or interest payments when they are due. In the worst case, unsustainable debt levels can cause a decline in the value of the dollar (which may lead to inflation), and can prevent the U.S. government from implementing effective counter-cyclical fiscal policy in economic downturns. On August 5, 2011, Standard & Poor's Ratings Services downgraded U.S. Treasury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

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accordance with the terms of the securities) in increases in interest rates through upward adjustments of the coupon rates on the securities. However, during periods of increasing interest rates, changes in the coupon rates may lag behind the changes in market rates or may have limits on the maximum increases in coupon rates. Alternatively, during periods of declining interest rates, the coupon rates on such securities will typically readjust downward resulting in a lower yield. A Fund may also invest in variable or floating rate equity securities, whose dividend payments vary based on changes in market rates of interest or other factors.

Additional Information About Non-Principal Investment Strategies and Risks

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result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

SSGA FM serves as the investment adviser to each Fund and corresponding Portfolio and, subject to the oversight of the Board, is responsible for the investment management of each Fund. The Adviser provides an investment management program for each Fund and manages the investment of each Fund's assets. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation. The Adviser is registered with the SEC under the Investment Advisers Act of 1940, as amended. The Adviser and certain other affiliates of State Street Corporation make up SSGA. SSGA is one of the world's largest institutional money managers and the investment management arm of State Street Corporation. As of December 31, 2021, the Adviser managed approximately $841.33 billion in assets and SSGA managed approximately $4.14 trillion in assets. The Adviser's principal business address is One Iron Street, Boston, Massachusetts 02210.

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.05% for Treasury Portfolio, 0.05% for Treasury Plus Portfolio and 0.05% for U.S. Government Portfolio.

Total Annual Fund Operating Expense Waivers. SSGA FM, as the investment adviser to each Fund is contractually obligated until April 30, 2023 to reimburse each Fund for expenses to the extent that Total Annual Fund Operating Expenses (exclusive of interest, brokerage commissions, taxes, extraordinary expenses, deferred organizational expenses or acquired fund fees and expenses) of the Select Class shares of each Fund exceed 0.08% of average daily net assets on an annual basis. This reimbursement arrangement for Select Class shares of the Fund may not be terminated prior to April 30, 2023 except with approval of the Board.

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A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one-day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

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Shareholder Information

Determination of Net Asset Value

The Treasury Plus Fund and the U.S. Government Fund each determines its NAV per share once each day on which the New York Stock Exchange (the “NYSE”), the Federal Reserve banks and State Street are open for business (a “Business Day”) at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event those Funds will determines their NAVs at the earlier closing time. The Treasury Fund determines its NAV per share once each Business Day at 2:30 p.m. ET, or the close of the NYSE, whichever is earlier (the time when a Fund determines its NAV per share is referred to herein as the “Valuation Time”). Each Fund seeks to maintain a $1.00 per share NAV and, accordingly, uses the amortized cost valuation method, in compliance with the risk limiting conditions of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”), to value its portfolio instruments. The amortized cost valuation method initially prices an instrument at its cost and thereafter assumes a constant amortization to maturity of any discount or premium, regardless of the impact of fluctuating interest rates on the market value of the instrument.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

Eligible investors of the Select Class Shares of the Funds generally are limited to institutional entities that hold Fund Shares directly with a Fund, as opposed to through a broker, bank or other financial intermediary.

Investors pay no sales load to invest in the Select Class Shares of the Funds. Purchase requests received by a Fund in good order (a purchase request is in good order if it meets the requirements implemented from time to time by the Transfer Agent or authorized agent of the Fund, and for new accounts includes submission of a completed and signed appli-

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cation and all documentation necessary to open an account) on a Business Day will, if payment is received by FedWire, be priced at the NAV next determined after the order is accepted by the Fund. Payments received by FedWire prior to the last Valuation Times will earn dividend accrual for that purchase.

The minimum initial investment in Select Class of the Funds is $750 million, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include, but are not limited to, accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Funds and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below).The Funds require prior notification of subsequent investments in excess of $10 million for the Treasury Fund and $50 million for the U.S. Government Fund and Treasury Plus Fund.

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How to Purchase Shares

By Mail:

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form.

For the U.S. Government Fund, Treasury Fund and the Treasury Plus Fund

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a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;
c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

For all Funds

A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Funds will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Funds calculate their NAVs earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Funds may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of a Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Currently, exchanging shares is allowed from/to each Fund. Exchanges may be made between different Funds within the same class (i.e. , Select Class shares for Select Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

Dividends, Distributions and Tax Considerations

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Each Fund invests substantially all of its investible assets in a corresponding Portfolio that is treated as a partnership for U.S. federal income tax purposes. Therefore, the nature and character of each Fund's income, gains, losses and deductions generally will be determined at the Portfolio level, and each Fund will be allocated its share of the corresponding Portfolio's income, gains, losses and deductions. As applicable, references in this discussion to income, gains and losses of a Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of a Fund will be to the Fund's allocable share of the assets of the corresponding Portfolio.

A Fund's and the Portfolio's income from or proceeds of investments in non-U.S. assets may be subject to non-U.S. withholding and other taxes. This will decrease the Fund's return on securities subject to such taxes. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes. Although such taxes will reduce a Fund's taxable income, shareholders generally will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Portfolio or Fund.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

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Financial Highlights

The Select Class shares of the Funds had not commenced operations prior to the date of this Prospectus and therefore do not have financial information.

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments will be available in the Funds' most recent annual and semi-annual reports to shareholders. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports will be available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, or will be available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

MULTISLCTSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

State Street Institutional
Investment Trust

State Street International Value Spotlight Fund

Class A (-----) Class I (-----) Class K (SIVSX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in the Fund offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund may offer multiple classes of shares. This Prospectus covers only the Class A, Class I and Class K Shares of the Fund.

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Fund Summary	1
State Street International Value Spotlight Fund	1
Additional Information About Investment Objective, Principal Strategies and Risks	9
Additional Information About Non-Principal Investment Strategies and Risks	19
Portfolio Holdings Disclosure	21
Management and Organization	22
Shareholder Information	23
Dividends, Distributions and Tax Considerations	36
Financial Intermediary Arrangements	38
Financial Highlights	40

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State Street International Value Spotlight Fund

Investment Objective

The State Street International Value Spotlight Fund (the “International Value Spotlight Fund” or sometimes referred to in context as the “Fund”) seeks to provide long-term growth of capital.

Fees and Expenses of the Fund

The tables below describe the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Fund Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries which are not reflected in the tables and examples below. You may qualify for sales charge discounts on purchases of Class A shares if you agree to invest in the future, or if you and your family currently invest, at least $50,000 in State Street Funds that offer Class A shares. More information about these and other discounts is available from your financial intermediary (“Financial Intermediary”) and in Choosing a Share Class – Reducing Your Class A Sales Charge on page 40% of the Fund's Prospectus.

Shareholder Fees (fees paid directly from your investment)

	Class A	Class I	Class K
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None¹	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class A	Class I	Class K
Management Fee	0.75%	0.75%	0.75%
Distribution and/or Shareholder Service (12b-1) Fees	0.25%	0.00%	0.00%
Other Expenses²	6.63%	6.63%	6.43%
Total Annual Fund Operating Expenses	7.63%	7.38%	7.18%
Less Fee Waivers and/or Expense Reimbursements³	(6.43%)	(6.43%)	(6.43%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	1.20%	0.95%	0.75%

¹	A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.
²	Other Expenses are based on estimates for the current fiscal year for Class A and Class I shares.

Example:

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	1 year	3 years	5 years	10 years
Class A	$641	$2,102	$3,488	$6,646
Class I	$97	$1,596	$3,025	$6,310
Class K	$77	$1,541	$2,943	$6,187

Portfolio Turnover:

Principal Investment Strategies

The International Value Spotlight Fund invests principally in a portfolio of equity securities of non-U.S. issuers from around the world that State Street Global Advisors Europe Limited (“SSGA Europe” or the “Sub-Adviser”) believes are undervalued. SSGA Europe uses a proprietary fundamental research-based process to identify companies where it believes there is a dislocation between the value of a company and the price of its equity securities, utilizing a proprietary integrated suite of security-specific financial analyses and valuation tools to analyze and model relevant aspects of a company's operational and financial performance in order to arrive at an estimate of the intrinsic value of a security. After identifying a universe of such companies, SSGA Europe selects for investment those companies within such universe that it believes represent the optimal combination of long-term value and quality. The Fund expects typically to invest most of its assets in equity securities of issuers in the MSCI ACWI ex USA Index, but may invest any portion of its assets in other issuers. The Fund is a non-diversified investment company.

Under normal circumstances, the Fund will invest at least 80% of its net assets (plus borrowings, if any, for investment purposes) in securities of non-U.S. issuers, which may include issuers from both developed and emerging markets countries. SSGA Europe considers a company to be a non-U.S. issuer if a company meets one of the following criteria: (i) it is organized outside the United States or maintains a principal place of business outside the United States; (ii) its securities are traded principally outside the United States; or (iii) during its most recent fiscal year, it derived at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed outside the United States or it has at least 50% of its assets outside the United States.

Under normal circumstances, at least 90% of the Fund's net assets will be invested in publicly traded securities. The Fund expects to invest primarily in common stocks, but may also invest in preferred stocks, securities convertible into common or preferred stocks, and depositary receipts. The Fund may purchase securities in their initial public offerings, and may hold securities that are restricted as to resale. Equity securities held by the Fund may be denominated in non-U.S. currencies and may be held outside the United States, which may include both developed and emerging markets countries. The Fund also may invest in the securities of Chinese companies, normally restricted to residents of the People's Republic of China (commonly known as “A Shares” or “China A Shares”), through the Stock Connect program or other channels. The Fund may invest in other investment companies, including exchange-traded funds, to the extent permitted by applicable law (including those advised by SSGA Funds Management, Inc., the Fund's investment adviser). The Fund may hold a portion of its assets in cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by SSGA Funds Management, Inc. or an affiliate). While the Fund may invest in companies of any market capitalization, it expects to primarily invest in large capitalization companies. The Fund may invest in derivatives, such as futures contracts, in order to gain broad equity market exposures pending investments of cash, or to reduce market exposures pending the sales of securities. The Fund may enter into foreign currency futures and forward contracts to hedge currency risk, although the Adviser does not currently anticipate that such transactions will play any significant role in the Fund's investment process.

Principal Risks

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and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund may not achieve its investment objective. The Fund is not intended to be a complete investment program, but rather is intended for investment as part of a diversified investment portfolio. Investors should consult their own advisers as to the role of the Fund in their overall investment programs.

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Currency Hedging Risk: If the Fund enters into currency hedging transactions, any loss generated by those transactions generally should be substantially offset by gains on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the hedging transaction and the risk sought to be hedged. There can be no assurance that the Fund's hedging transactions will be effective.

Derivatives Risk: Derivative transactions can create investment leverage and may have significant volatility. It is possible that a derivative transaction will result in a much greater loss than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Fund's margin, or otherwise honor its obligations. A derivatives transaction may not behave in the manner anticipated by the Sub-Adviser or may not have the effect on the Fund anticipated by the Sub-Adviser.

Emerging Markets Risk: Risks of investing in emerging markets include, among others, greater political and economic instability, greater volatility in currency exchange rates, less developed securities markets, possible trade barriers, currency transfer restrictions, a more limited number of potential buyers and issuers, an emerging market country's dependence on revenue from particular commodities or international aid, less governmental supervision and regulation, unavailability of currency hedging techniques, differences in auditing and financial reporting standards, less stringent investor protection and disclosure standards, less developed public health systems, and less developed legal systems. There is also the potential for unfavorable action such as expropriation, nationalization, embargo, and acts of war. The securities of emerging market companies may trade less frequently and in smaller volumes than more widely held securities. Market disruptions or substantial market corrections may limit very significantly the liquidity of securities of certain companies in a particular country or geographic region, or of all companies in the country or region. The Fund may be unable to liquidate its positions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. These risks are generally greater for investments in frontier market countries, which typically have smaller economies or less developed capital markets than traditional emerging market countries.

Management Risk: The Fund is actively managed. The Sub-Adviser's judgments about the attractiveness, relative value, or potential appreciation of a particular sector, security, commodity or investment strategy may prove to be incorrect, and may cause the Fund to incur losses. There can be no assurance that the Sub-Adviser's investment techniques and decisions will produce the desired results.

Modeling Risk: The Sub-Adviser uses quantitative models in an effort to enhance returns and manage risk. Any imperfections, errors or limitations in these models could limit any benefit to the Fund from the use of the models, or could result in incorrect outputs or in investment outcomes different from or opposite to those expected or desired by

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the Sub-Adviser. There can be no assurance that the models will behave as expected in all market conditions. In addition, computer programming used to create quantitative models, or the data on which such models operate, might contain one or more errors.

Non-Diversification Risk: As a “non-diversified” mutual fund, the Fund may hold a smaller number of portfolio securities than many other funds. To the extent the Fund invests in a relatively small number of issuers, a decline in the market value of a particular security held by the Fund may affect its value more than if it invested in a larger number of issuers. The value of Fund Shares may be more volatile than the values of shares of more diversified funds.

Risk of Investment in Other Pools: If the Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected and is exposed indirectly to all of the risks applicable to an investment in such other pool. The investment policies of the other pool may not be the same as those of the Fund; as a result, an investment in the other pool may be subject to additional or different risks than those to which the Fund is typically subject. The Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Sub-Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. It is possible that other clients of the Sub-Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Sub-Adviser or its affiliates at prices and at times more favorable than those at which the Fund does so.

Risks Related to Screening: The Fund employs a proprietary screen to identify securities within the Fund's investment universe, based on criteria related to its investment objective. There is a risk that errors are made in the screening process. Errors may include, but are not limited to, incorrect constituents and incorrect assessment of the relevant screening criteria.

Stock Connect Investing Risk: The Fund's ability to achieve its investment objective may depend on its continued ability to invest in China “A Shares.” A Shares are equity securities of issuers incorporated in mainland China that are denominated and currently traded in Renminbi (“RMB”) on the Shanghai or Shenzhen Stock Exchanges. The Fund may invest in A Shares listed and traded on the Shanghai Stock Exchange or Shenzhen Stock Exchange through the Stock Connect program, or on such other stock exchanges in China, which participate in the Stock Connect program from time to time. The Fund's investments in Stock Connect A Shares are generally subject to Chinese securities regulations and listing rules, among other restrictions that may affect the Fund's investments and returns, including daily limits on net purchases and transfer restrictions. Such investments are also subject to heightened tax and settlement risk and the risk of price fluctuations of A Shares during times when the Stock Connect program is not trading. The Stock Connect program is a relatively new program. Further developments are likely and there can be no assurance as to the program's continued existence or whether future developments regarding the program may restrict or adversely affect the Fund's investments or returns.

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tions in such securities at any time, or at a favorable price, in order to meet the Fund's obligations. Returns on investments in securities of small-, mid- and micro-capitalization companies could trail the returns on investments in securities of larger companies.

Value Stock Risk: A “value” style of investing is subject to the risk that the returns on “value” equity securities are less than returns on other styles of investing or the overall stock market. Value stocks present the risk that they may decline in price or never reach their expected full market value, either because the market fails to recognize a stock's intrinsic worth or the Sub-Adviser overestimates the stock's expected value.

Performance

The bar chart and table below provide some indication of the risks of investing in the International Value Spotlight Fund by illustrating the variability of the Fund's returns from year-to-year and by showing how the Fund's average annual returns for the periods indicated compared with those of the Index. The bar chart shows how the Class K shares' returns have varied for each full calendar year shown. Except for differences in returns resulting from differences in fees and expenses, all share classes would have substantially similar returns because all share classes invest in the same portfolio of securities. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (800) 997-7327 or by visiting our website at www.ssga.com.

Annual Total Return (years ended 12/31)

Highest Quarterly Return: 19.54% (Q4, 2020)
Lowest Quarterly Return: -26.00% (Q1, 2020)

Average Annual Total Returns (for periods ended 12/31/21)

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	One Year	Five Years	Since Inception	Inception Date
Class K				7/13/2016
Return Before Taxes	3.90%	6.39%	8.49%
Return After Taxes on Distributions	3.16%	3.78%	5.90%
Return After Taxes on Distributions and Sale of Fund Shares	2.48%	4.00%	5.69%
MSCI ACWI ex USA Index (reflects no deduction for fees, expenses or taxes other than withholding taxes on reinvested dividends)	7.82%	9.61%	9.34%

The Fund will make updated performance information, including its current net asset value, available at the Fund's website: www.ssga.com.

Investment Adviser and Sub-Adviser

SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), serves as the investment adviser to the Fund. SSGA Europe, an affiliate of the Adviser, serves as investment sub-adviser to the Fund, subject to supervision by the Adviser and oversight by the Trust's Board of Trustees. To the extent that a reference in this Prospectus refers to the Adviser, with respect to the Fund, such reference should also be read to refer to SSGA Europe, where the context requires.

The professional primarily responsible for the day-to-day management of the Fund is Barry Glavin who has been portfolio manager for the Fund since inception in 2016.

Barry Glavin, CFA, is a Senior Managing Director of SSGA Europe and Chief Investment Officer of SSGA Europe's Dublin-based Fundamental Value Team. He joined SSGA Europe in 2006.

Purchase and Sale of Fund Shares

Purchase Minimums

Class A
To establish an account	$2,000
To add to an existing account	None
Class I
To establish an account	None
To add to an existing account	None
Class K
To establish an account	None
To add to an existing account	None

You may purchase or redeem Fund Shares on any day the Fund is open for business.

Written Requests and Wire Transfers. You may purchase or redeem Fund Shares by written request or wire transfer.

Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight/Registered, Express, Certified Mail:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

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By Intermediary:

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objective, Principal Strategies and Risks

Investment Objective

Principal Investment Strategies

Additional Information About Risks

The Fund is subject to the following principal risks. The risks are described in alphabetical order and not in the order of importance or potential exposure.

Convertible Securities Risk. Convertible securities are bonds, debentures, notes, preferred stocks or other securities that may be converted or exchanged (by the holder or by the issuer, depending on the terms of the securities) into shares of the underlying common stock (or cash or securities of equivalent value) at a stated exchange ratio. Convertible securities may be subordinate to other debt securities issued by the same issuer. Issuers of convertible securities are often not as strong financially as issuers with higher credit ratings. Convertible securities typically provide yields lower than comparable non-convertible securities. Their values may be more volatile than those of non-convertible securities, reflecting changes in the values of the securities into which they are convertible.

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Currency Hedging Risk. If a derivative is used as a hedge against a position that the Fund holds, any gain generated by the derivative generally should be substantially offset by losses on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between a derivative and its reference asset. Furthermore, while the Fund may hedge against currency fluctuations, it is possible that a degree of currency exposure may remain even at the time a hedging transaction is implemented. As a result, changes in currency exchange rates may affect Fund returns even when the hedge works as intended. The effectiveness of the Fund's currency hedging strategy will also generally be affected by the volatility of both the securities included in the Index, and the volatility of the U.S. dollar relative to the currencies to be hedged. Increased volatility may reduce the effectiveness of the Fund's currency hedging strategy and may impact the costs associated with hedging transactions. The effectiveness of the Fund's currency hedging strategy and the costs associated with hedging transactions may also in general be affected by interest rates. Significant differences between U.S. dollar interest rates and foreign currency interest rates may further impact the effectiveness of the Fund's currency hedging strategy. There can be no assurance that the Fund's hedging transactions will be effective. The Fund's currency hedging activities will potentially increase or accelerate distributions to shareholders, increase distributions taxed to individuals as ordinary income, result in the re-characterization of prior ordinary income distributions as return of capital, or generate losses that cannot be used to offset income or capital gain in subsequent years. The Fund will bear the costs associated with any such hedging transaction, regardless of any gain or loss experienced on the hedging transaction.

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is denominated in a different currency than its underlying securities, the Fund will be subject to the currency risk of both the investment in the depositary receipt and the underlying security. There may be less publicly available information regarding the issuer of the securities underlying a depositary receipt than if those securities were traded directly in U.S. securities markets. Depositary receipts may or may not be sponsored by the issuers of the underlying securities, and information regarding issuers of securities underlying unsponsored depositary receipts may be more limited than for sponsored depositary receipts. The values of depositary receipts may decline for a number of reasons relating to the issuers or sponsors of the depositary receipts, including, but not limited to, insolvency of the issuer or sponsor. Holders of depositary receipts may have limited or no rights to take action with respect to the underlying securities or to compel the issuer of the receipts to take action. The prices of depositary receipts may differ from the prices of securities upon which they are based.

Derivatives Risk. A derivative is a financial contract the value of which depends on, or is derived from, the value of an underlying asset, interest rate, or index. Derivative transactions typically involve leverage and may have significant volatility. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, that changes in the value of a derivative transaction may not correlate perfectly with the underlying asset, and that the Fund may not be able to close out a derivative transaction at a favorable time or price. Risks associated with derivative instruments include potential changes in value in response to interest rate changes or other market developments or as a result of the counterparty's credit quality; the potential for the derivative transaction not to have the effect the Sub-Adviser anticipated or a different or less favorable effect than the Sub-Adviser anticipated; the failure of the counterparty to the derivative transaction to perform its obligations under the transaction or to settle a trade; possible mispricing or improper valuation of the derivative instrument; imperfect correlation in the value of a derivative with the asset, rate, or index underlying the derivative; the risk that the Fund may be required to post collateral or margin with its counterparty, and will not be able to recover the collateral or margin in the event of the counterparty's insolvency or bankruptcy; the risk that the Fund will experience losses on its derivatives investments and on its other portfolio investments, even when the derivatives investments may be intended in part or entirely to hedge those portfolio investments; the risks specific to the asset underlying the derivative instrument; lack of liquidity for the derivative instrument, including, without limitation, absence of a secondary trading market; the potential for reduced returns to the Fund due to losses on the transaction and an increase in volatility; the potential for the derivative transaction to have the effect of accelerating the recognition of gain; and legal risks arising from the documentation relating to the derivative transaction.

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Forward Currency Contracts Risk. In a forward currency contract, the Fund agrees to buy in the future an amount in one currency in return for another currency, at an exchange rate determined at the time the contract is entered into. If currency exchange rates move against the Fund's position during the term of the contract, the Fund will lose money on the contract. There is no limit on the extent to which exchange rates may move against the Fund's position. The markets for certain currencies may at times become illiquid, and the Fund may be unable to enter into new forward contracts or to close out existing contracts. Forward currency contracts are entered into in the over-the-counter market, and the Fund's ability to profit from a contract will depend on the willingness and ability of its counterparty to perform its obligations under the contract. Use by the Fund of foreign currency forward contracts may give rise to investment leverage.

Futures Contract Risk; Other Exchange-Traded Derivatives Risk. The risk of loss relating to the use of futures contracts and other exchange-traded derivatives is potentially unlimited. The ability to establish and close out positions in futures contracts and other exchange-traded derivatives will be subject to the development and maintenance of a liquid secondary market. There is no assurance that a liquid secondary market on an exchange will exist for any particular futures contract or other exchange-traded derivative or at any particular time. In the event no such market exists for a particular derivative, it might not be possible to effect closing transactions, and the Fund will be unable to terminate the derivative. In using futures contracts and other exchange-traded derivatives, the Fund will be reliant on the ability of the Adviser to predict market and price movements correctly; the skills needed to use such derivatives successfully are different from those needed for traditional portfolio management. If the Fund uses futures contracts or other exchange-traded derivatives for hedging purposes, there is a risk of imperfect correlation between movements in the prices of the derivatives and movements in the securities or index underlying the derivatives or movements in the prices of the Fund's investments that are the subject of such hedge. The prices of futures and other exchange-traded derivatives, for a number of reasons, may not correlate perfectly with movements in the securities or index underlying them. For example, participants in the futures markets and in markets for other exchange-traded derivatives are subject to margin deposit requirements. Such requirements may cause investors to take actions with respect to their derivatives positions that they would not otherwise take. The margin requirements in the derivatives markets may be less onerous than margin requirements in the securities markets in general, and as a result those markets may attract more speculators than the securities markets do. Increased participation by speculators in those markets may cause temporary price distortions. Due to the possibility of price distortion, even a correct forecast of general market trends by the Adviser still may not result in a successful derivatives activity over a very short time period. The risk of a position in a futures contract or other exchange-traded derivative may be very large compared to the relatively low level of margin the Fund is required to deposit. In many cases, a relatively small price movement in a futures contract may result in immediate and substantial loss or gain to the investor relative to the size of a required margin deposit. The Fund will incur brokerage fees in connection with its exchange-traded derivatives transactions. The Fund will typically be required to post margin with its futures commission merchant in connection with its transactions in futures contracts and other exchange-traded derivatives. In the event of an insolvency of the futures commission merchant or a clearing house, the Fund may not be able to recover all (or any) of the margin it has posted with the futures commission merchant, or to realize the value of any increase in the price of its positions, or it may experience a significant delay in doing so. The Fund also may be delayed or prevented from recovering margin or other amounts deposited with a futures commission merchant or futures clearinghouse. The Commodity Futures Trading Commission (the “CFTC”) and the various exchanges have established limits referred to as “speculative position limits” on the maximum net long or net short positions that any person and certain affiliated entities may hold or control in a particular futures contract. Trading limits are imposed on the number of contracts that any person may trade on a particular trading day. An exchange may order the liquidation of positions found to be in violation of these limits and it may impose sanctions or restrictions. In addition, the Dodd-Frank Act requires the CFTC to establish speculative position limits on certain commodity futures contracts and their economically equivalent futures, options and swaps. Regulatory action taken by the CFTC to establish these additional position limits may adversely affect the market liquidity of the futures, options and economically equivalent derivatives in which the Fund may invest. It is possible that, as a result of such limits, the Fund's Adviser will be precluded from taking positions in certain futures contracts or over-the-counter derivatives as a result of positions held by other clients of the Adviser or by the Adviser or its affiliates themselves.

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IPO Risk. The Fund may at times have the opportunity to invest in securities offered in initial public offerings (“IPOs”). IPOs involve companies that have no public operating history and therefore entail more risk than established public companies. The prices of securities offered in IPOs can have significant volatility and the Fund may lose money on an investment in such securities. IPOs may not be available to the Fund at all times, and the Fund may not always invest in IPOs offered to it. Investments in IPOs may have a substantial beneficial effect on the Fund's investment performance. The Fund's investment return earned during a period of substantial investment in IPOs may not be sustained during other periods when the Fund makes more limited, or no, investments in IPOs. There can be no assurance that the Fund will have the opportunity to invest in IPOs that are made available to other clients of the Adviser or any Sub-Adviser.

Large Shareholder Risk. To the extent a large proportion of the shares of the Fund are highly concentrated or held by a small number of shareholders (or a single shareholder), including funds or accounts over which the Adviser has investment discretion, the Fund is subject to the risk that these shareholders will purchase or redeem Fund shares in large amounts rapidly or unexpectedly, including as a result of an asset allocation decision made by the Adviser. These transactions could adversely affect the ability of the Fund to conduct its investment program. For example, they could require the Fund to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to shareholders, or the Fund may be required to sell its more liquid portfolio investments to meet a large redemption, in which case the Fund's remaining assets may be less liquid, more volatile, and more difficult to price. The Fund may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Leveraging Risk. Borrowing transactions, reverse repurchase agreements, certain derivatives transactions, securities lending transactions and other investment transactions such as when-issued, delayed-delivery, or forward commitment transactions may create investment leverage. If the Fund engages in transactions that have a leveraging effect on the Fund's investment portfolio, the value of the Fund will be potentially more volatile and all other risks will tend to be compounded. This is because leverage generally creates investment risk with respect to a larger base of assets than the Fund would otherwise have and so magnifies the effect of any increase or decrease in the value of the Fund's underlying assets. The use of leverage is considered to be a speculative investment practice and may result in losses to the Fund. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The use of leverage may cause the Fund to liquidate positions when it may not be advantageous to do so to satisfy repayment, interest payment, or margin obligations or to meet asset segregation or coverage requirements.

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most LIBOR settings on a representative basis at the end of 2021 and is expected to cease publication of a majority of U.S. dollar LIBOR settings on a representative basis after June 30, 2023. In addition, global regulators have announced that, with limited exceptions, no new LIBOR-based contracts should be entered into after 2021. Actions by regulators have resulted in the establishment of alternative reference rates to LIBOR in most major currencies. Various financial industry groups have been planning for the transition away from LIBOR and markets are developing in response to these new rates, but questions around the liquidity of the new rates and how to appropriately adjust these rates to eliminate any economic value transfer at the time of transition remain a significant concern. The transition away from and eventual elimination of LIBOR may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, particularly insofar as the documentation governing such instruments does not include “fall back” provisions addressing the transition from LIBOR. Uncertainty and volatility arising from the transition may result in a reduction in the value of certain LIBOR-based instruments held by the Fund or reduce the effectiveness of related transactions such as hedges. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Fund.

Management Risk. The Fund is actively managed. The Adviser's and Sub-Adviser's judgments about the attractiveness, relative value, or potential appreciation of a particular sector, security, commodity or investment strategy may prove to be incorrect, and may cause the Fund to incur losses. There can be no assurance that the Adviser's and Sub-Adviser's investment techniques and decisions will produce the desired results.

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ber 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by the Fund. To the extent the Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

Market Volatility; Government Intervention Risk. Market dislocations and other external events, such as the failures or near failures of significant financial institutions, dislocations in investment or currency markets, corporate or governmental defaults or credit downgrades, or poor collateral performance, may subject the Fund to significant risk of substantial volatility and loss. Governmental and regulatory authorities have taken, and may in the future take, actions to provide or arrange credit supports to financial institutions whose operations have been compromised by credit market dislocations and to restore liquidity and stability to financial systems in their jurisdictions; the implementation of such governmental interventions and their impact on both the markets generally and the Fund's investment program in particular can be uncertain. Governmental and non-governmental issuers may default on, or be forced to restructure, their debts, and other issuers may face difficulties obtaining credit. Defaults or restructurings by governments or others of their debts could have substantial adverse effects on economies, financial markets, and asset valuations around the world. Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases or contrary actions by different governments, or investor perception that these efforts are not succeeding, could negatively affect financial markets generally as well as the values and liquidity of certain securities.

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that the models will behave as expected in all market conditions. In addition, computer programming used to create quantitative models, or the data on which such models operate, might contain one or more errors. Such errors might never be detected, or might be detected only after the Fund has sustained a loss (or reduced performance) related to such errors.

Non-Diversification Risk. As a “non-diversified” fund, the Fund may hold a smaller number of portfolio securities than many other mutual funds. To the extent the Fund invests in a relatively small number of issuers, a decline in the market value of a particular security held by the Fund may affect its value more than if it invested in a larger number of issuers. The value of Fund Shares may be more volatile than the values of shares of more diversified funds.

Preferred Securities Risk. Generally, preferred security holders have no or limited voting rights with respect to the issuing company. In addition, preferred securities are subordinated to bonds and other debt instruments in a company's capital structure and therefore will be subject to greater credit risk than those debt instruments. Unlike debt securities, dividend payments on a preferred security typically must be declared by the issuer's board of directors. An issuer's board of directors is generally not under any obligation to pay a dividend (even if such dividends have accrued), and may suspend payment of dividends on preferred securities at any time. Therefore, in the event an issuer of preferred securities experiences economic difficulties, the issuer's preferred securities may lose substantial value due to the reduced likelihood that the issuer's board of directors will declare a dividend and the fact that the preferred security may be subordinated to other securities of the same issuer. Further, because many preferred securities pay dividends at a fixed rate, their market price can be sensitive to changes in interest rates in a manner similar to bonds - that is, as interest rates rise, the value of the preferred securities held by the Fund are likely to decline. Therefore, to the extent that the Fund invests a substantial portion of its assets in fixed rate preferred securities, rising interest rates may cause the value of the Fund's investments to decline significantly. In addition, because many preferred securities allow holders to convert the preferred securities into common stock of the issuer, their market price can be sensitive to changes in the value of the issuer's common stock and, therefore, declining common stock values may also cause the value of the Fund's investments to decline. Preferred securities often have call features, which allow the issuer to redeem the security at its discretion. The redemption of a preferred security having a higher than average yield may cause a decrease in the Fund's yield.

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and (vi) the nature of the security and the nature of marketplace trades. There can be no assurance that a liquid trading market will exist at any time for any particular restricted security. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

Risks Related to Screening. The Fund employs a proprietary screen to identify securities within the Fund's investment universe, based on criteria related to its investment objective. There is a risk that errors are made in the screening process. Errors may include, but are not limited to, incorrect constituents and incorrect assessment of the relevant screening criteria.

Special Risk Considerations of Investing in China . Investing in securities of Chinese issuers, including by investing in A Shares, involves certain risks and considerations not typically associated with investing in securities of U.S. issuers, including, among others, (i) more frequent (and potentially widespread) trading suspensions and U.S. or foreign government interventions or restrictions with respect to Chinese issuers, which could preclude the Fund from making certain investments or result in the Fund selling investments at disadvantageous times and which may also cause reduced liquidity and increased price volatility in such investments, (ii) the nature and extent of intervention by the Chinese government in the Chinese securities markets, whether such intervention will continue and the impact of such intervention or its discontinuation, (iii) the risk of nationalization or expropriation of assets, (iv) the risk that the Chinese government may decide not to continue to support economic reform programs, (v) limitations on the use of brokers, (vi) potentially higher rates of inflation, (vii) the unavailability of consistently-reliable economic data, (viii) the relatively small size and absence of operating history of many Chinese companies, (ix) accounting, auditing and financial reporting standards in China are different from U.S. standards and, therefore, disclosure of certain material information may not be available, (x) greater political, economic, social, legal and tax-related uncertainty, (xi) higher market volatility caused by any potential regional territorial conflicts or natural disasters, (xii) higher dependence on exports and international trade, (xiii) the risk of increased trade tariffs, sanctions, embargoes and other trade limitations, (xiv) restrictions on foreign ownership, and (xv) custody risks associated with investing through programs to access Chinese securities. Significant portions of the Chinese

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securities markets may become rapidly illiquid, as Chinese issuers have the ability to suspend the trading of their equity securities, and have shown a willingness to exercise that option in response to market volatility and other events. The liquidity of Chinese securities may shrink or disappear suddenly and without warning as a result of adverse economic, market or political events, or adverse investor perceptions, whether or not accurate.

Stock Connect Investing Risk . The Fund's ability to achieve its investment objective may depend on its continued ability to invest in China “A Shares.” A Shares are equity securities of issuers incorporated in mainland China that are denominated and currently traded in RMB on the Shanghai or Shenzhen Stock Exchanges. Subject to minor exceptions, under current regulations in China, foreign investors, such as the Fund, can invest in A Shares only (i) through certain institutional investors that have obtained a license and quota from the Chinese regulators or (ii) through the Hong Kong-Shanghai Stock Connect or Shenzhen-Hong Kong Stock Connect programs. The Fund may invest in A Shares listed and traded on the Shanghai Stock Exchange or Shenzhen Stock Exchange through the Stock Connect program, or on such other stock exchanges in China, which participate in the Stock Connect program from time to time. The Fund's investments in Stock Connect A Shares are generally subject to Chinese securities regulations and listing rules, among other restrictions that may affect the Fund's investments and returns, including daily limits on net purchases and transfer restrictions. In addition, the Stock Connect program's trading, clearance and settlement procedures are relatively untested in China, which could pose risks to the Fund. While overseas investors currently are exempt from paying capital gains or value added taxes on income and gains from investments in Stock Connect A Shares, these Chinese tax rules could be changed, which could result in unexpected tax liabilities for the Fund.

The Stock Connect program will only operate on days when both the Chinese and Hong Kong markets are open for trading and when banks in both markets are open on the corresponding settlement days. There may be occasions when the Fund may be subject to the risk of price fluctuations of A Shares during the time when the Stock Connect program is not trading. Because of the way in which China A shares are held in Stock Connect, the Fund may not be able to exercise the rights of a shareholder and may be limited in its ability to pursue claims against the issuer of a security, and may suffer losses in the event the depository of the Shanghai or Shenzhen Stock Exchanges becomes insolvent. Only certain China A shares are eligible to be accessed through the Stock Connect program. Such securities may lose their eligibility at any time, in which case they presumably could be sold but could no longer be purchased through the Stock Connect program. The Stock Connect program is a relatively new program. Further developments are likely and there can be no assurance as to the program's continued existence or whether future developments regarding the program may restrict or adversely affect the Fund's investments or returns. In addition, the application and interpretation of the laws and regulations of Hong Kong and China, and the rules, policies or guidelines published or applied by relevant regulators and exchanges in respect of the Stock Connect program are uncertain, and they may have a detrimental effect on the Fund's investments and returns.

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it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

Value Stock Risk. Value stocks present the risk that they may decline in price or never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the Sub-Adviser overestimates the stock's expected value. Value stocks may underperform growth stocks and stocks in other broad style categories (and the stock market as a whole) over any period of time and may shift in and out of favor with investors generally, sometimes rapidly, depending on changes in market, economic, and other factors. As a result, at times when it holds substantial investments in value stocks the Fund may underperform other investment portfolios that invest more broadly or that favor different investment styles.

Additional Information About Non-Principal Investment Strategies and Risks

The Adviser and its affiliates serve as investment adviser to other clients and may make investment decisions that may be different from those that will be made by the Adviser on behalf of the Fund. For example, the Adviser may provide asset allocation advice to some clients that may include a recommendation to invest in or redeem from particular issuers while not providing that same recommendation to all clients invested in the same or similar issuers. The Adviser may (subject to applicable law) be simultaneously seeking to purchase (or sell) investments for the Fund and to sell (or purchase) the same investment for accounts, funds, or structured products for which it serves as asset manager, or for other clients or affiliates. The Adviser and its affiliates may invest for clients in various securities that are senior, pari passu or junior to, or have interests different from or adverse to, the securities that are owned by the Fund. The Adviser or its affiliates, in connection with its other business activities, may acquire material nonpublic confidential information that may restrict the Adviser from purchasing securities or selling securities for itself or its clients (including the Fund) or otherwise using such information for the benefit of its clients or itself.

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actions, shareholder ownership of Fund Shares, and other data integral to the functioning of the Fund inaccessible or inaccurate or incomplete. The Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. The Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. The Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Fund. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund's investment in such securities to lose value.

Portfolio Turnover Risk. The Fund may engage in frequent trading of its portfolio securities. Fund turnover generally involves a number of direct and indirect costs and expenses to the Fund, including, for example, brokerage commissions, dealer mark-ups and bid/asked spreads, and transaction costs on the sale of securities and reinvestment in other securities. The costs related to increased portfolio turnover have the effect of reducing the Fund's investment return, and the sale of securities by the Fund may result in the realization of taxable capital gains, including short-term capital gains, which are taxed to individuals as ordinary income.

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ment vehicle advised by the Adviser. With respect to index funds, to the extent the collateral provided or investments made with cash collateral differ from securities included in the relevant Index, such collateral or investments may have a greater risk of loss than the securities included in the Index. In addition, the Fund will be subject to the risk that any income generated by reinvesting cash collateral is lower than any fees the Fund has agreed to pay a borrower.

Temporary Defensive Positions. In response to actual or perceived adverse market, economic, political, or other conditions, the Fund may (but will not necessarily), without notice, depart from its principal investment strategies by temporarily investing for defensive purposes. Temporary defensive positions may include, but are not limited to, cash, cash equivalents, U.S. government securities, repurchase agreements collateralized by such securities, money market funds, and high-quality debt investments. While investing defensively, the Fund may maintain a substantial portion of its assets in cash, on which the Fund may earn little if any income. If the Fund invests for defensive purposes, it may not achieve its investment objective. In addition, the defensive strategy may not work as intended.

Portfolio Holdings Disclosure

The Fund's portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

The Fund is a separate, non-diversified series of the State Street Institutional Investment Trust (the “Trust”), which is an open-end management investment company organized as a business trust under the laws of the Commonwealth of Massachusetts.

Investment Adviser

Investment Sub-Adviser. SSGA Europe, 78 Sir John Rogerson's Quay, Dublin 2, Ireland, a wholly-owned subsidiary of State Street Corporation, serves as the investment sub-adviser to SSGA FM with respect to the Fund. As of December 31, 2021, SSGA Europe managed approximately $470.83 billion in assets with differing investment objectives across a variety of investment strategies and product types.

The Fund has entered into an investment advisory agreement with the Adviser, pursuant to which the Adviser will manage the Fund's assets, for compensation paid at an annual rate of 0.75% of the International Value Spotlight Fund's average daily net assets. The Adviser has entered into a sub-advisory agreement with the Sub-Adviser pursuant to which the Sub-Adviser will be responsible for the day-to-day management of any assets of the Fund. The Sub-Adviser receives fees from the Adviser for its services provided to the Fund.

Total Annual Fund Operating Expense Waiver. SSGA FM, as the investment adviser to the Fund, is contractually obligated, through April 30, 2023, (i) to waive up to the full amount of the advisory fee payable by the Fund, and/or (ii) to reimburse the Fund to the extent that Total Annual Fund Operating Expenses (exclusive of non-recurring account fees, interest, taxes, extraordinary expenses, acquired fund fees, any class-specific expenses, such as distribution, shareholder servicing, sub-transfer agency and administration fees) exceed average daily net assets on an annual basis of 0.70% for the Fund. These waiver and/or reimbursement arrangements may not be terminated prior to April 30, 2023 except with approval of the Fund's Board .

A discussion regarding the Board's consideration of the Fund's Investment Advisory Agreement and Sub-Advisory Agreement is provided in the Fund's Annual Report to Shareholders for the period ended June 30, 2021.

SSGA FM, as the investment adviser for the Fund, may hire one or more sub-advisers to oversee the day-to-day investment activities of the Fund. The sub-advisers are subject to oversight by the Adviser. The Adviser and the Trust have received an exemptive order from the SEC that permits the Adviser, with the approval of the Independent Trustees of the Trust to retain, and to amend contractual arrangements with unaffiliated investment sub-advisers for the Fund without a vote of the Fund's shareholders. The Trust will notify shareholders in the event of any change in the identity of a sub-adviser or sub-advisers of any Fund. The Adviser is not required to disclose fees paid to any individual sub-adviser retained pursuant to the order. The Sub-Adviser places all orders for purchases and sales of the Fund's investments.

Portfolio Management

The Adviser and Sub-Adviser manage the fund using one portfolio manager, who is responsible for its performance. The `buy discipline' for portfolio manager is to select stocks from the pool, which they believe have the most upside to our estimate of intrinsic value, in which they share the Adviser and Sub-Adviser's conviction that the assumptions are robust, and which the portfolio manager believes will help construct a well-balanced, diversified portfolio. The portfolio manager is overseen by the SSGA Investment Committee.

The professional primarily responsible for the day-to-day management of the Fund is Barry Glavin.

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Barry Glavin, CFA, is the Chief Investment Officer of SSGA Europe's Dublin-based Fundamental Value Team and the Portfolio Manager responsible for the International Value Spotlight Strategy. He is a member of the SSGA Europe Senior Management Group, a member of the SSGA Investment Committee and sits on the SSGA Executive Management Group. He joined the business in November 2006 as Head of Industrials Research and led the Research Team for six years until his appointment as CIO in July 2013. Prior to joining SSGA Europe, Mr. Glavin spent seven years with the HSBC group in London, as Head of Industrials Research with HSBC Halbis Partners, and in Paris, as a Portfolio Manager with the Multi Asset Class team. Barry began his financial career as a derivatives broker with Cargill Investor Services in Paris. Barry holds a Bachelor of Arts in Politics and Philosophy from University College Dublin and earned the Chartered Financial Analyst (CFA) designation in 2003.

Additional information about the portfolio manager's compensation, other accounts managed by the portfolio manager, and the portfolio manager's ownership of the Fund is available in the SAI.

Other Fund Services

The Administrator, Sub-Administrator and Custodian

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Fund's transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Fund's distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

Additional Information

Shareholder Information

Determination of Net Asset Value

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Fund's Shares. Purchase and redemption orders for Fund Shares are processed, respectively, at the NAV next determined after the Fund accepts a purchase order or receives a redemption request in good form. The Fund values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Fund's Board, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by the Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price the Fund would have received had it sold the investment. To the extent that the Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published NAVs per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

Choosing a Share Class

The Fund offers three classes of shares through this Prospectus: Class A, Class I and Class K, available to you subject to the eligibility requirements set forth below.

When you buy Class A shares, the initial sales load is deducted from the amount you invest, unless you qualify for an initial sales load waiver. This means that less money will be invested in the Fund immediately. Class A shares have a Rule 12b-1 fee of 0.25% per year. A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on redemptions of Class A shares made within 18 months after purchase where no initial sales charge was paid at the time of purchase as part of an investment of $1,000,000 or more.

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	Class A	Class I	Class K
Availability	Available to the general public through certain Financial Intermediaries.	Limited to certain investors serviced through a Financial Intermediary receiving a fee from the applicable Fund for shareholder servicing or similar services.	Limited to certain investors, including certain financial institutions, qualified recordkeepers and employer-sponsored retirement plans.
Minimum Initial Investment	$2,000. The investment minimum may be modified, waived or reduced for certain types of investors (e.g., 401(k) or 403(b) plans) and investments as well as for certain fee-based programs where an agreement is in place.	There is no minimum investment for Class I shares.	There is no minimum investment for Class K shares.
Maximum Investment	None.	None.	None.
Initial (Front-End) Sales Charge	Yes. 5.25% for Equity Funds and 3.75% for Fixed Income Funds, payable at time of purchase. Lower sales charges are available for larger investments. See the chart under “Class A” section of this Prospectus.	No. Entire purchase price is invested in shares of the Fund.	No. Entire purchase price is invested in shares of the Fund.
Deferred (CDSC) Sales Charge	No, except for purchases of $1,000,000 or more that are redeemed within 18 months after purchase.	No.	No.
Distribution and Service (12b-1) Fees	0.25% annual fee.	No.	No.
Redemption Fees	No.	No.	No.

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Class A

Class A shares are available to the general public for investment through qualified recordkeepers with a distribution and/or fund servicing agreement maintained with SSGA FD.

When you buy Class A shares, you pay an initial (or front-end) sales charge at the time of your investment, which is included in the offering price, unless you qualify for a sales charge reduction or waiver. This fee is deducted from the amount you invest, and the remainder of your money is used to buy shares in the Fund. The table below shows the amount of sales charge you would pay at different levels of investment and the commissions paid to Financial Intermediaries at each level of investment. The actual sales charge you pay may vary slightly from the rates disclosed due to rounding.

Amount of Purchase Payment	Sales Charge as a % of Offering Price	Sales Charge as a % of Net Amount Invested	Financial Intermediary Compensation as a % of Offering Price
Less than $50,000	5.25%	5.54%	4.75%
$50,000-$99,999	4.50%	4.71%	4.00%
$100,000-$249,999	3.50%	3.63%	3.25%
$250,000-$499,999	2.50%	2.56%	2.25%
$500,000-$999,999	2.00%	2.04%	1.75%
$1,000,000 or more	None	None	Advanced Commission^{1, 2}

¹	Class A advanced commission for purchases over $1 million:

1.00%	First $3 million
Plus 0.50%	Next $12 million
Plus 0.25%	Over $15 million

Reducing Your Class A Sales Charge

The Fund offers two principal ways for you to qualify for discounts on initial sales charges on Class A share purchases, often referred to as “breakpoint discounts”: Right of Accumulation or a Letter of Intent. Each of these methods is described below. In taking advantage of these methods for reducing the initial sales charge you will pay, you may link purchases of shares of all of the State Street Funds that offer Class A shares in which you invest (as described below) even if such State Street Funds are held in accounts with different Financial Intermediaries, as well as purchases of Class I and Class N shares of all State Street Funds (other than shares of money market funds) to be held in accounts owned by your spouse or domestic partner and children under the age of 21 who share your residential address. It is your responsibility when investing to inform your Financial Intermediary or the State Street Funds that you would like to have one or more of the State Street Funds linked together for purposes of reducing the initial sales charge.

1.	Your account(s);
2.	Account(s) of your spouse or domestic partner;
3.	Account(s) of children under the age of 21 who share your residential address;
4.	Trust accounts established by any of the individuals in items (1) through (3) above. If the person(s) who established the trust is deceased, the trust account may be aggregated with the account(s) of the primary beneficiary of the trust;
5.	Solely controlled business accounts; and
6.	Single-participant retirement plans of any of the individuals in items (1) through (3) above.

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Gifting of Shares. If you make a gift of shares, upon your request, you may combine purchases, if made at the same time, under right of accumulation of Class A, Class I and Class N shares of a State Street Fund (other than any shares of money market funds) at the sales charge discount allowed for the combined purchase. The receiver of the gift may also be entitled to a prospective reduction in sales charges in accordance with the Fund's right of accumulation or other provisions. You or the receiver of the gift must provide certain account information to State Street or their agents at the time of purchase to exercise this right.

Letter of Intent. In order to immediately reduce your Class A sales charge, you may sign a Letter of Intent stating your intention to buy a specified amount of Class A shares of one or more State Street Funds within a 13-month period at the reduced sales charge rates applicable to the aggregate amount of the intended purchases stated in the Letter. Purchases of Class A shares of one or more State Street Funds you make over the 13- month period will be combined and you will pay the same sales charge on the new Class A shares that you would have paid if all shares were purchased at once. The 13-month Letter of Intent period commences on the day that the Letter of Intent is received by the Fund or your Financial Intermediary. Purchases submitted not more than three months prior to the date the Letter of Intent is received are considered in determining the level of sales charge that will be paid pursuant to the Letter of Intent; however, the Letter of Intent will not result in any reduction in the amount of any previously paid sales charge. In addition, investors do not receive credit for shares purchased by the reinvestment of distributions.

Waiver Of The Class A Sales Charge

A sales charge (“load”) may not be imposed on Class A shares of the Fund if the shares were:

1.	Acquired through the reinvestment of dividends and capital gain distributions.
2.	Acquired in exchange for shares of another Class A State Street Fund that were previously assessed a sales charge. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares at the same CDSC rate.
3.	Bought in State Street Funds that do not offer Class N (no load) shares¹ by officers, directors or trustees, retirees and employees and their immediate family members (i.e., spouses, domestic partners, children, grandchildren, parents, grandparents, and any dependent of the person, as defined in Section 152 of the Internal Revenue Code of 1986 (the “Code”)) of:

•	The State Street Funds
•	State Street Corporation and its subsidiaries and affiliates

¹	State Street Funds that offer Class N Shares include: State Street Defensive Emerging Markets Equity Fund (SSEMX), State Street International Stock Selection Fund (SSAIX) and State Street S&P 500 Index Fund (SVSPX).

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4.	Bought by employees of:

•

DST Asset Manager Solutions, Inc. and its subsidiaries and affiliates.

•

5.	Bought by:

•	Authorized retirement plans serviced or sponsored by a Financial Intermediary, provided that such Financial Intermediary has entered into an agreement with SSGA FD or with the Fund with respect to such purchases at NAV.
•	Investors who are directly rolling over or transferring shares from an established State Street Fund or State Street qualified retirement plan. Rolling over or transferring shares involves the transferring of shares (in-kind); there is no cash movement associated with the transaction.
•	Clients of Financial Intermediaries that (i) charge an ongoing fee for advisory, management, consulting or similar services, or (ii) have entered into an agreement with SSGA FD to offer Class A shares through a no-load network or platform, or self-directed brokerage accounts that may or may not charge transaction fees to customers.
•	Insurance company separate accounts.
•	Tuition Programs that qualify under Section 529 of the Code.

6.	Bought with proceeds from the sale of Class A shares of a State Street Fund, but only if the purchase is made within 90 days of the sale or distribution. Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.
7.	Bought in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which the Fund is a party. However, you may pay a CDSC when you sell the Fund Shares you received in connection with the plan of reorganization.

Additional Sales Charge Waiver Disclosure

How the CDSC is Calculated

The State Street Funds calculate the CDSC by treating all purchases made in a given month as though they were made on the first day of the month.

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You should retain any records necessary to substantiate historical costs because SSGA FD, the Fund, the transfer agent and your Financial Intermediary may not maintain such information.

Waiver of the CDSC

In the following situations, no CDSC is imposed on redemptions of Class A shares of the Fund:

1.	If you participate in the Automatic Withdrawal Plan. Redemptions made on a regular periodic basis (e.g. monthly) will not be subject to any applicable CDSC if they are, in the aggregate, less than or equal to 10% annually of the current market value of the account balance. Redemptions made as part of a required minimum distribution are also included in calculating amounts eligible for this waiver. For information on the Automatic Withdrawal Plan, please see Service Options.
2.	If you are a registered participant or beneficial owner of an account and you die or become disabled (as defined in Section 72(m)(7) of the Code). This waiver is only available for accounts open prior to the shareholder's or beneficiary's death or disability, and the redemption must be made within one year of such event. Subsequent purchases into such account are not eligible for the CDSC waiver. In order to qualify for this waiver, SSGA FD must be notified of such death or disability at the time of the redemption order and be provided with satisfactory evidence of such death or disability.
3.	Redemptions that represent a required minimum distribution from your IRA Account or other qualifying retirement plan but only if you are at least age 72 or age 70 ½ if you reached age 70 ½ prior to January 1, 2020. If you maintain more than one IRA, only the assets credited to the IRA that is invested in one or more of the State Street Funds are considered when calculating that portion of your minimum required distribution that qualifies for the waiver.
4.	A distribution from a qualified retirement plan by reason of the participant's retirement.
5.	Redemptions that are involuntary and result from a failure to maintain the required minimum balance in an account.
6.	Exchanges in connection with plans of reorganization of a State Street Fund, such as mergers, asset acquisitions and exchange offers to which the Fund is a party. However, you may pay a sales charge when you redeem the Fund Shares you receive in connection with the plan of reorganization.
7.	Exchanges for shares of the same class of another State Street Fund. However, if your shares are subject to CDSC, the CDSC will continue to apply to your new shares. For purposes of the CDSC, shares will continue to age from the date of the original purchase of the Fund Shares.
8.	Redemption of shares purchased through employer sponsored retirement plans and deferred compensation plans. The CDSC, however, will not be waived if the plan redeems all of the shares that it owns on behalf of participants prior to the applicable CDSC period, as defined above.
9.	Redemptions as part of annual IRA custodial fees.
10.	Acquired through the reinvestment of dividends and capital gains distributions.

Appropriate documentation may be required. Please refer to Class A Account Reinstatement Privileges below.

Class A Account Reinstatement Privileges

Class I

Class I shares are available to the following categories of investors serviced through a Financial Intermediary receiving a fee from a Fund for shareholder servicing or similar services:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) that have entered into agreements with the Fund to purchase Class I shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund “supermarkets”;
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

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2.	Defined contribution, defined benefit and other employer-sponsored employee benefit plans, whether or not qualified under the Code.

There is no minimum investment for Class I shares.

Class K

Class K shares are available to the following categories of investors:

1.	Banks, broker-dealers and other financial institutions (including registered investment advisers and financial planners) purchasing Fund Shares on behalf of their clients in:

•	Discretionary and non-discretionary advisory programs;
•	Fund "supermarkets";
•	Asset allocation programs;
•	Other programs in which the client pays an asset-based fee for advice or for executing transactions in Fund Shares or for otherwise participating in the program; or
•	Certain other investment programs that do not charge an asset-based fee;

2.	Qualified recordkeepers with an applicable agreement maintained with SSGA FD;
3.	Endowments and foundations, and defined contribution, defined benefit, and other employer-sponsored employee benefit plans, whether or not qualified under the Code;
4.	Certain other registered open-end investment companies whose shares are distributed by SSGA FD;
5.	Current or retired Directors or Trustees of the State Street Funds, officers and employees of SSGA, and any of its subsidiaries, such persons' spouses, and children under the age of 21, and trust accounts for which any of such person is a beneficiary;
6.	Qualified state tuition plans described in Section 529 of the Code and donor-advised charitable gift funds (subject to all applicable terms and conditions);
7.	Health Savings Accounts under Section 223 of the Code if such accounts are maintained by the Fund at an omnibus level;
8.	Collective investment trusts.

There is no minimum investment for Class K shares.

How to Initiate a Purchase Request

Investing in the State Street Funds Through a Financial Intermediary

Account Applications and Other Documents. You may find many of the forms necessary to open an account online or by calling or writing to the State Street Funds. See Contacting the State Street Funds.

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Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

How to Pay for a Purchase

By Check. You may send a check to make initial or additional purchases to your fund account. Make your check payable to “State Street Funds” and include the appropriate fund name and account number (e.g., “State Street International Value Spotlight Fund—a/c #xxx”) in the memo section of the check.

Trade Dates-Purchases

If your purchase request is not in good order, it may be rejected.

For further information about purchase transactions, consult our website at www.ssga.com or see Contacting the State Street Funds.

Other Purchase Policies You Should Know

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Redeeming Shares

By Telephone. You may call the State Street Funds to request a redemption of shares. See Contacting the State Street Funds.

By Mail. You may send a written request to the State Street Funds to redeem from the Fund account or to make an exchange. See Contacting the State Street Funds.

Please be sure to check Exchanging Shares and Frequent-Trading Limits below.

Trade Date-Redemptions

The trade date for any redemption request received in good order will depend on the day and time the State Street Funds receive your request in good order and the manner in which you are redeeming.

How to Receive Redemption Proceeds

Regardless of the method the Fund use to make a redemption payment, the Fund typically expect to pay out redemption proceeds on the next business day after a redemption request is received in good order. If you purchased State Street Fund Shares by check or an automatic investment program and you elect to redeem shares within 15 days of the purchase, you may experience delays in receiving redemption proceeds. In this case, the State Street Funds generally will postpone sending redemption proceeds until it can verify that the check or automatic investment program investment has been collected, but in no event will this delay exceed 15 days. There will be no such delay for redemptions following purchases paid by federal funds wire or by bank cashier's check, certified check or treasurer's check. The State Street Funds reserve the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund. The State Street Funds reserve the right to suspend the right of shareholder redemption or postpone the date of payment for more than seven days to the extent permitted by the 1940 Act.

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Other Redemption Policies that You Should Know

Address Changes. If your address of record has been changed within thirty (30) days of the redemption request, the request must be in writing and bear a medallion guarantee.

Significant/Unusual Economic or Market Activity. During periods of significant or unusual economic or market activity, you may encounter delays attempting to give instructions by phone.

Exchanging Shares

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Share Class Conversions

Frequent-Trading Limits

Frequent, short-term trading, abusive trading practices and market timing (together, “Excessive Trading”), often in response to short-term fluctuations in the market, are not knowingly permitted by the State Street Funds. The State Street Funds do not accommodate frequent purchases and redemptions of Fund Shares by Fund shareholders. Excessive Trading into and out of a State Street Fund may harm the Fund's performance by disrupting portfolio management strategies and by increasing expenses. These expenses are borne by all Fund shareholders, including long-term investors who do not generate such costs.

As a means to protect each State Street Fund and its shareholders from Excessive Trading:

•	The State Street Funds' transfer agent compiles, monitors and reports account-level information on omnibus and underlying shareholder/participant activity. Depending on the account type, monitoring will be performed on a daily, monthly, quarterly and/or annual basis;
•	The State Street Funds' distributor has obtained information from each Financial Intermediary holding shares in an omnibus account with the State Street Funds regarding whether the Financial Intermediary has adopted and maintains procedures that are reasonably designed to protect the Fund against harmful short-term trading; and

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•	With respect to State Street Funds that invest in securities that trade on foreign markets, pursuant to the State Street Funds' fair valuation procedures, pricing adjustments may be made based on information received from a third-party, multi-factor fair valuation pricing service.

The State Street Funds' distributor has detailed procedures that document the transparency oversight and monitoring processes performed by the State Street Funds' transfer agent.

Service Options

Dividend and Capital Gain Distribution Option

Please refer to Dividends, Distributions and Tax Considerations below for additional information.

Automatic Withdrawal Plan

Telephone Redemptions and Exchanges

Automatic Investment Plan

Once the initial investment has been accepted, you may make subsequent investments of $100 or more monthly, quarterly or annually by direct deposit by debiting your bank checking or savings account. Once this option has been established, you may call the State Street Funds to make additional automatic purchases, to change the amount of the existing automatic purchase, or to stop it. The State Street Fund reserves the right to cancel your automatic investment plan if any correspondence sent by the Fund is returned by the postal or other delivery service as “undeliverable.”

Additional Shareholder Information

Account Transfers

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Responsibility for Fraud

Right to Change Policies

In addition to the rights expressly stated elsewhere in this Prospectus, the State Street Funds reserve the right, in the future, to:

1.	Alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, service, or privilege at any time;
2.	Accept initial purchases by telephone;
3.	Freeze any account and/or suspend account services if the State Street Funds has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if we reasonably believe a fraudulent transaction may occur or has occurred;
4.	Temporarily freeze any account and/or suspend account services upon initial notification to the State Street Funds of the death of the shareholder until the State Street Funds receive required documentation in good order;
5.	Alter, impose, discontinue, or waive any redemption fee, account service fee, or other fees charged to a group of shareholders; and
6.	Redeem an account or suspend account privileges, without the owner's permission to do so, in cases of threatening conduct or activity the State Street Funds believe to be suspicious, fraudulent, or illegal.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If the Fund's transfer agent identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund).

Dividends, Distributions and Tax Considerations

Distribution Options. You can choose from four different distribution options as indicated on the application:

•	Reinvestment Option—Dividends and capital gain distributions will be automatically reinvested in additional shares of the Fund. If you do not indicate a choice on the application, this option will be automatically assigned.
•	Income-Earned Option—Capital gain distributions will be automatically reinvested, but a check, direct deposit or wire will be sent for each dividend distribution.
•	Cash Option—A check, wire or direct deposit will be sent for each dividend and capital gain distribution.
•	Direct Dividends Option—Dividends and capital gain distributions will be automatically invested in another identically registered State Street Fund of the same share class.

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Delivery of Documents to Accounts Sharing an Address

Tax Considerations

The Fund has elected to be treated as a regulated investment company and intends each year to qualify and to be eligible to be treated as such. A regulated investment company generally is not subject to tax at the corporate level on income and gains that are timely distributed to shareholders. In order to qualify and be eligible for treatment as a regulated investment company, the Fund must, among other things, satisfy diversification, 90% gross income and distribution requirements. The Fund's failure to qualify and be eligible for treatment as a regulated investment company would result in corporate level taxation, and consequently, a reduction in income available for distribution to shareholders.

For U.S. federal income tax purposes, distributions of investment income generally are taxable to you as ordinary income. Taxes on distributions of capital gains generally are determined by how long the Fund owned (or is deemed to have owned) the investments that generated them, rather than how long you have owned your Fund Shares. Distributions of net capital gains (that is, the excess of net long-term capital gains over net short-term capital losses) from the sale of investments that the Fund owned (or is deemed to have owned) for more than one year that are properly reported by the Fund as capital gain dividends generally will be treated as long-term capital gain includible in your net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that the Fund owned (or is deemed to have owned) for one year or less generally will be taxable to you as ordinary income. Distributions of investment income properly reported by the Fund as derived from “qualified dividend income,” which will not include income from the Fund's portfolio securities on loan, are taxed to individuals at the rates applicable to net capital gain, provided holding period and other requirements are met by both the shareholder and the Fund. Distributions are taxable to you even if they are paid from income or gains earned by the Fund before your investment (and thus were included in the price you paid for your shares). Distributions may also be subject to state and local taxes and are taxable whether you receive them in cash or reinvest them in additional shares. Distributions in excess of the Fund's current and accumulated earnings and profits are treated as a return of capital to the extent of your basis in the applicable Fund's shares, and, in general, as capital gain thereafter.

An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by the Fund, including any capital gain dividends, and net gains recognized on the redemption of Fund Shares.

The Fund's income from or proceeds of dispositions of its investments in non-U.S. assets may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. In certain instances, the Fund may be entitled to elect to pass through to its shareholders a credit (or deduction, for a shareholder that itemizes deductions and so chooses) for foreign taxes (if any) borne with respect to foreign securities income earned by the Fund. If the Fund so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the Fund. There can be no assurance that the Fund will make such election, even if it is eligible to do so. If

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the Fund does not qualify for or does not make such election, shareholders will not be entitled separately to claim a credit or deduction with respect to foreign taxes incurred by the Fund; in that case the foreign tax will nonetheless reduce the Fund's taxable income. Shareholders that are not subject to U.S. federal income tax, and those who invest in the Fund through tax-advantaged accounts (including those who invest through IRAs or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit or deduction passed through by the Fund. Under certain circumstances, if a Fund receives a refund of foreign taxes paid in respect of a prior year, the value of Fund Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Fund's foreign taxes for the current year could be reduced.

Certain of the Fund's investment practices, including derivative transactions and investments in debt obligations issued or purchased at a discount, will be subject to special and complex U.S. federal income tax provisions. These special rules may affect the timing, character, and/or amount of the Fund's distributions, and may require the Fund to sell its investments at a time when it is not advantageous to do so.

The U.S. Treasury and the Internal Revenue Service (the “IRS”) generally require the Fund to obtain information sufficient to identify the status of each shareholder under sections 1471-1474 of the Code, and the U.S. Treasury and IRS guidance issued thereunder (collectively, the “Foreign Account Tax Compliance Act” or “FATCA”) or under an applicable intergovernmental agreement between the United States and a foreign government. Please see the SAI for more information on FATCA reporting requirements.

Cost Basis Reporting. U.S. Treasury regulations mandate cost basis reporting to shareholders and the IRS for redemptions of Fund Shares acquired on or after January 1, 2012 (“Post Effective Date Shares”). If you acquire and hold shares directly through the Fund and not through a Financial Intermediary, DST Asset Manager Solutions, Inc. will use a default average cost basis methodology for tracking and reporting your cost basis on Post Effective Date Shares, unless you request, in writing, another cost basis reporting methodology.

Financial Intermediary Arrangements

Distribution Arrangements and Rule 12b-1 Fees

The Fund has adopted a distribution plan pursuant to Rule 12b-1 under the 1940 Act under which the Fund may compensate SSGA FD (or others) for services in connection with the distribution of the Fund's Class A shares and for services provided to shareholders in that class (the “Plan”). The Plan calls for payments at an annual rate (based on average daily net assets) of 0.25% of the Fund's net assets attributable to its Class A shares. Because these fees are paid out of the assets of the Fund attributable to its Class A shares on an ongoing basis, they will increase the cost of your investment and may cost you more over time than paying other types of sales charges.

The Fund may pay distribution fees and other amounts described in this Prospectus at a time when shares of the Fund are unavailable for purchase.

Other Payments to Financial Intermediaries

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The Financial Intermediary is often compensated by SSGA FD or its affiliates for the services it performs and in such cases is typically paid continually over time, during the period when the Financial Intermediary's clients hold investments in the Fund. The amount of continuing compensation paid by SSGA FD or its affiliates to different Financial Intermediaries for distribution and/or shareholder services varies. Any compensation is typically a percentage of the value of the Financial Intermediary's clients' investments in the Fund or a per account fee. The variation in compensation may, but will not necessarily, reflect enhanced or additional services provided by the Financial Intermediary.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide other compensation to Financial Intermediaries in connection with sales of the Fund's shares or the servicing of shareholders or shareholder accounts. Such compensation may include, but is not limited to, financial assistance to Financial Intermediaries in connection with conferences, sales, or training programs for their employees; seminars for the public; advertising or sales campaigns; or other Financial Intermediary-sponsored special events. In some instances, this compensation may be made available only to certain Financial Intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Dealers may not use sales of the Fund's shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA.

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Financial Highlights

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INTERNATIONAL VALUE SPOTLIGHT FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Class K
	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19	Year Ended 12/31/18	Year Ended 12/31/17
Net asset value, beginning of period	$10.15	$9.54	$8.08	$12.56	$11.25
Income (loss) from investment operations:
Net investment income (loss) (a)	0.22	0.15	0.18	0.21	0.24
Net realized and unrealized gain (loss)	0.18	0.57	1.47	(2.66)	2.56
Total from investment operations	0.40	0.72	1.65	(2.45)	2.80
Voluntary contribution from Adviser	—	0.04	—	—	—
Distributions to shareholders from:
Net investment income	(0.23)	(0.15)	(0.19)	(0.22)	(0.24)
Net realized gains	—	—	—	(1.81)	(1.25)
Total distributions	(0.23)	(0.15)	(0.19)	(2.03)	(1.49)
Net asset value, end of period	$10.32	$10.15	$9.54	$8.08	$12.56
Total return (b)	3.90%	8.01%(c)	20.39%	(19.32)%	25.03%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$2,064	$2,031	$1,907	$1,617	$2,512
Ratios to average net assets:
Total expenses	7.18%	11.20%	12.74%	7.58%	7.26%
Net expenses	0.75%	0.75%	0.75%	0.75%	0.75%
Net investment income (loss)	2.04%	1.70%	2.09%	1.76%	1.86%
Portfolio turnover rate	40%	76%	35%	63%	45%

(a)	Net investment income per share is calculated using the average shares method.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	If an affiliate had not made a contribution during the period ended December 31, 2020, the total return would have been 7.59%.

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Contacting the State Street Funds

Online:	www.ssga.com	24 hours a day, 7 days a week
Phone:	(800) 647-7327	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Fund:

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSITVSLSTATPRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

This prospectus is intended for use only by clients of Bancroft Capital, LLC.

State Street Institutional
Investment Trust

State Street ESG Liquid Reserves Fund

Bancroft Capital Class (VTEXX)

State Street Institutional Liquid Reserves Fund

Bancroft Capital Class (VTDXX)

State Street Institutional Treasury Money Market Fund

Bancroft Capital Class (VTTXX)

State Street Institutional Treasury Plus Money Market Fund

Bancroft Capital Class (VTLXX)

State Street Institutional U.S. Government Money Market Fund

Bancroft Capital Class (VTGXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Bancroft Capital Class Shares of the applicable Funds.

State Street ESG Liquid Reserves Fund and State Street Institutional Liquid Reserves Fund are “floating net asset value” money market funds. The share price of these Funds will fluctuate.

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Fund Summaries	1
State Street ESG Liquid Reserves Fund	1
State Street Institutional Liquid Reserves Fund	9
State Street Institutional Treasury Money Market Fund	16
State Street Institutional Treasury Plus Money Market Fund	21
State Street Institutional U.S. Government Money Market Fund	26
Additional Information About Investment Objectives, Principal Strategies and Risks	32
Additional Information About Non-Principal Investment Strategies and Risks	44
Portfolio Holdings Disclosure	46
Management and Organization	47
Shareholder Information	49
Dividends, Distributions and Tax Considerations	56
Financial Intermediary Arrangements	58
Financial Highlights	60

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State Street ESG Liquid Reserves Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.13%
Total Annual Fund Operating Expenses	0.18%
Less Fee Waivers and/or Expense Reimbursements²	(0.03%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

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1 year		3 years		5 years		10 years
$15		$55		$98		$227

Principal Investment Strategies

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Principal Risks

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agement of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

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Performance

The bar chart and table below provide some indication of the risks of investing in the ESG Liquid Reserves Fund by illustrating the variability of the Fund's returns from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Bancroft Capital Class shares are new. Returns of the Bancroft Capital Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Bancroft Capital Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.27% (Q2, 2020)
Lowest Quarterly Return: 0.01% (Q4, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Since Inception		Inception Date
Premier Class		0.07%		0.39%		12/3/2019

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Bancroft Capital Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Bancroft Capital LLC and its affiliates.

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You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Liquid Reserves Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

Principal Investment Strategies

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interest rates, as well as imbalances of supply and demand in the market. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds, which require, among other things, the Fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity.

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

Principal Risks

The Fund is subject to the following principal risks. You could lose money by investing in the Fund. Because the share price of the Fund will fluctuate, when you sell your shares, they may be worth more or less than what you originally paid for them. The Fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares if the Fund's liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is subject to investment risks, including possible loss of principal, is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. Certain risks relating to instruments and strategies used in the management of the Fund are placed first. The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the ILR Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Bancroft Capital Class shares are new. Returns of the Bancroft Capital Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Bancroft Capital Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.65% (Q1, 2019)
Lowest Quarterly Return: 0.00% (Q4, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.04%		1.20%		0.69%		8/12/2004

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Bancroft Capital Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Bancroft Capital LLC and its affiliates.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

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By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

Principal Risks

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Bancroft Capital Class shares are new. Returns of the Bancroft Capital Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Bancroft Capital Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.57% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.01%		1.00%		0.52%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Bancroft Capital Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Bancroft Capital LLC and its affiliates.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

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By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

Principal Risks

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sion, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Bancroft Capital Class shares are new. Returns of the Bancroft Capital Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Bancroft Capital Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.02%		1.01%		0.52%		10/24/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Bancroft Capital Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Bancroft Capital LLC and its affiliates.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Bancroft Capital Class shares are new. Returns of the Bancroft Capital Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Bancroft Capital Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.03%		1.02%		0.54%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Bancroft Capital Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Bancroft Capital LLC and its affiliates.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

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By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the ESG Liquid Reserves Fund, ILR Fund, Treasury Fund, Treasury Plus Fund and U.S. Government Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

ESG Liquid Reserves Fund

Principal Investment Strategies

The Adviser intends to consider ESG criteria at the time of purchase by using an ESG-related metric for each Fund investment. For most Fund investments, the Adviser uses a proprietary scoring system developed by SSGA that assigns an ESG rating, in the form of a “Responsibility” or “R-Factor^TM” score, to the issuer. The amount of the Fund's investments assigned an R-Factor^TM score will vary from time to time and can change significantly. The R-Factor^TM score measures the performance of a company's business operations and governance as related to financially material ESG challenges facing the issuer's industry. For example, for companies in the asset management industry, the R- FactorTM score currently uses metrics based on selling practices and product labeling, employee engagement / diversity and inclusion, product design and lifecycle management, business ethics, and systemic risk management. The R-Factor^TM score for each applicable issuer draws on a number of data sources, including third-party data providers, that provide metrics on a variety of ESG topics.

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ILR Fund

Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in a broad range of money market instruments. These may include, among other things: U.S. government securities, including U.S. Treasury bills, notes and bonds and other securities issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies or instrumentalities; certificates of deposits and time deposits of U.S. and foreign banks (including ECDs, ETDs and YCDs (as defined below), commercial paper and other high quality obligations of U.S. or foreign companies; asset-backed securities, including asset-backed commercial paper; mortgage-related securities, including non-governmental mortgage-related securities; and repurchase agreements. These instruments may bear fixed, variable or floating rates of interest or may be zero-coupon securities. The Fund also may invest in shares of other money market funds, including funds advised by the Adviser. Under normal market conditions, the Fund intends to invest more than 25% of its total assets in bank obligations. A substantial portion of the Fund may be invested in securities that are issued or traded pursuant to exemptions from registration under the federal securities laws.

Treasury Fund

Principal Investment Strategies

The Treasury Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government). The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

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Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

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The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

Counterparty Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund, Treasury Plus Fund and U.S. Government Fund). A Fund will be subject to credit risk with respect to the counterparties with which a Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, a Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Credit Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund, Treasury Plus Fund and U.S. Government Fund). Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by a Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

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Liquidity Risk (principal risk for the ESG Liquid Reserves Fund and ILR Fund). Liquidity risk is the risk that a Fund may not be able to dispose of investments readily at a favorable time or prices (or at all) or at prices approximating those at which a Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Fund may seek to borrow money to meet its obligations (including, among other things, redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity a Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

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Market Disruption and Geopolitical Risk. A Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of a Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU. Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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Money Market Risk (principal risk for the Treasury Fund, Treasury Plus Fund and U.S. Government Fund). An investment in a money market fund is not a deposit of any bank and is not insured or guaranteed by the FDIC or any other government agency. Although a money market fund generally seeks to preserve the value of its shares at $1.00 per share, there can be no assurance that it will do so, and it is possible to lose money by investing in a money market fund. A major or unexpected change in interest rates or a decline in the credit quality of an issuer or entity providing credit support, an inactive trading market for money market instruments, or adverse market, economic, industry, political, regulatory, geopolitical, and other conditions could cause a money market fund's share price to fall below $1.00. It is possible that a money market fund will issue and redeem shares at $1.00 per share at times when the fair value of the money market fund's portfolio per share is more or less than $1.00. A money market fund may be permitted or required to impose redemption fees or to impose limitations on redemptions during periods of high illiquidity in the markets for the investments held by it. None of State Street Corporation, State Street, State Street Global Advisors, SSGA FM or their affiliates (collectively, the “State Street Entities”) guarantee the value of an investment in a money market fund at $1.00 per share. Investors should have no expectation of capital support to a money market fund from the State Street Entities.

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tured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Rapid Changes in Interest Rates. The values of instruments held by a Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause a Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses would negatively affect the NAV per share of the ILR Fund and the ESG Liquid Reserves Fund, in the case of the U.S. Government Fund, Treasury Fund and Treasury Plus Fund, could impair the Fund's ability to maintain a stable share price of $1.00.

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Repurchase Agreement Risk (principal risk for the ESG Liquid Reserves Fund, ILR Fund, Treasury Plus Fund and U.S. Government Fund). A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund, which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

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Stable Share Price Risk (principal risk for the Treasury Fund, Treasury Plus Fund and U.S. Government Fund). If the market value of one or more of the Fund's investments changes substantially, the Fund may not be able to maintain a stable share price of $1.00. This risk typically is higher during periods of rapidly changing interest rates or when issuer credit quality generally is falling, and is made worse when the Fund experiences significant redemption requests.

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Additional Information About Non-Principal Investment Strategies and Risks

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Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Funds, the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

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Risk of Investment in Other Pools (risk for the Treasury Fund and Treasury Plus Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.00% for the ESG Liquid Reserves Portfolio, 0.05% for Money Market Portfolio, 0.05% for Treasury Portfolio, 0.05% for Treasury Plus Portfolio and 0.05% for U.S. Government Portfolio.

In addition to any contractual expense limitation for a Fund, which is described in the Fund Summaries, each of the Adviser and State Street Global Advisors Funds Distributors, LLC (each a “Service Provider”) may voluntarily reduce all or a portion of its fees and/or reimburse expenses for a Fund or a share class to the extent necessary to maintain a certain minimum net yield, which may vary from time to time in SSGA FM's sole discretion (any such waiver or reimbursement of expenses being referred to herein as a “Voluntary Reduction”). The Adviser may, in its sole discretion, implement the Voluntary Reduction for some Funds, or some share classes of a Fund, and not others. The amount of any Voluntary Reduction may differ between Funds and share classes in the Adviser's sole discretion. The business objectives of

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the Adviser and its affiliates and their broader relationships with certain Fund shareholders, Financial Intermediaries or distribution channels could give the Adviser an incentive to implement the Voluntary Reduction for some Funds or share classes and not others, or to implement it to a greater degree for some Funds or share classes than others. Under an agreement with the Service Providers relating to the Voluntary Reduction, the Funds and the Portfolios have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from a Fund.

A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. The Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one-day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement) which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

Additional Information

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Shareholder Information

Determination of Net Asset Value

For the ESG Liquid Reserves Fund and ILR Fund

Each Fund determines its NAV per share three times each day on which the New York Stock Exchange (the “NYSE”), the Federal Reserve banks and State Street are open for business (a “Business Day”) at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The price for Fund shares is the NAV next calculated after the purchase order is accepted by a Fund. Orders accepted before 12:00 p.m. will receive the 12:00 p.m. NAV, orders accepted before 3:00 p.m. will receive the 3:00 p.m. NAV, and orders accepted after 3:00 p.m. will receive 8:00 a.m. NAV calculated on the following Business Day. The Fund calculates its NAV to four decimal places.

The NAV of each class of a Fund's shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding. Each Fund values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board of Trustees, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by a Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent that a Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

For the U.S. Government Fund, Treasury Plus Fund and Treasury Fund

For all Funds

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Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

The Funds offer one class of shares through this Prospectus: Bancroft Capital Class is available to you subject to the eligibility requirements set forth below. The Fund's Bancroft Capital Class is offered only to clients of Bancroft Capital, LLC and its affiliates (collectively, Bancroft Clients). The Bancroft Capital Class may not be purchased directly from the Funds. Instead Bancroft Clients may purchase the Bancroft Capital Class shares through accounts maintained with Bancroft Capital, LLC or its affiliates. Bancroft Capital, LLC may impose policies, limitations and fees, which are different than those described herein. All classes of a Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. You should choose the class with the expense structure that best meets your needs for which you are eligible. In choosing a share class, you should consider the amount you plan to invest. Your investment professional can help you choose the share class that best suits your investment needs.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their family. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

	Bancroft Capital Class
Minimum Initial Investment	$25,000,000
Maximum Investment	None.
Initial Sales Charge	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No.

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	Bancroft Capital Class
Distribution and/or Service (12b-1) Fees	No.
Redemption Fees	No.

Investors pay no sales load to invest in the shares of the Funds. The price for Fund Shares is the NAV per share.

The minimum initial investment in Bancroft Capital Class shares of the Funds is $25 million, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include but are not limited to accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Funds and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below). The Funds require prior notification of subsequent investments in excess of $10 million for the Treasury Fund and $50 million for the Treasury Plus Fund and U.S. Government Fund.

The Funds reserve the right to cease accepting investments at any time or to reject any investment order. In addition, the Treasury Plus Fund and U.S. Government Fund may limit the amount of a purchase order received after 3:00 p.m. ET. The Treasury Fund may limit the amount of a purchase order received after 12:00 p.m. (noon) ET. The ESG Liquid Reserves Fund and ILR Fund each determine its respective NAV at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The 8:00 a.m., 12:00 p.m. and 3:00 p.m. NAV calculation times are intended to facilitate same day settlement.

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How to Purchase Shares

By Mail:

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form.

For the ESG Liquid Reserves Fund and ILR Fund

If a Fund receives a redemption order in good form prior to its last valuation time (generally, 3:00 p.m. ET, unless the Fund closes earlier) on a Business Day, the Fund typically sends payment for redeemed shares on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after the last valuation time (generally, 3:00 p.m. ET, unless the Fund closes earlier) a Fund typically expects to

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pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent). Each Fund reserves the right to pay for redeemed shares within seven days after receiving a redemption order if, in the judgment of the Adviser, an earlier payment could adversely affect the Fund.

Certain special limitations affecting redemptions. The SEC has implemented a number of requirements, including liquidity fees and redemption gates, for money market funds based on the amount of fund assets in “weekly liquid assets,” which generally includes cash, direct obligations of the U.S. government, certain other U.S. government or agency securities, and securities that will mature or are subject to a demand feature that is exercisable and payable within five Business Days. Each Fund will pass through to its investors any liquidity fee or suspension of redemptions imposed by its corresponding Portfolio on the same terms and conditions as imposed by the Portfolio on the Fund.

If a Portfolio's weekly liquid assets fall below 30% of its total assets and the Portfolio's Board of Trustees determines it is in the best interests of the Portfolio, the Portfolio may immediately impose a liquidity fee of no more than 2% and/or temporarily suspend redemptions for up to 10 Business Days in any 90 day period. If a Portfolio's weekly liquid assets fall below 10% of its total assets at the end of any Business Day, the Portfolio will impose a liquidity fee of 1% on all redemptions beginning on the next Business Day, unless the Portfolio's Board determines that imposing such a fee would not be in the best interests of the Portfolio or determines that a lower or higher fee (not to exceed 2%) would be in the best interests of the Portfolio, which would remain in effect until weekly liquid assets return to 30% or the Portfolio's Board determines that the fee is no longer in the best interests of the Portfolio. All liquidity fees payable by a Fund would be passed through to its shareholders, would be payable to its corresponding Portfolio and could offset any losses realized by the Portfolio when seeking to honor redemption requests. If liquidity fees are imposed or redemptions are suspended by a Portfolio, the corresponding Fund will notify shareholders on the Fund's website. Each Fund expects to treat such liquidity fees paid to its corresponding Portfolio as reducing proceeds paid to shareholders in redemption of Fund shares, and not constituting income to the Portfolio or the Fund. There may be circumstances under which a Fund may impose its own liquidity fees and/or suspend redemptions based on the level of the Fund's own weekly liquid assets, in which case the Fund will also provide notice to shareholders.

If a Portfolio's weekly liquid assets fall below 10% of its assets on a Business Day, the Portfolio may cease honoring redemptions and liquidate in the discretion of the Portfolio's Board. If a Fund is notified that its corresponding Portfolio's weekly liquid assets fall below 10% of the Portfolio's assets and the Portfolio has suspended redemptions and intends to liquidate, the Fund may also do so in the discretion of the Fund's Board. There may be circumstances under which a Fund may cease honoring redemptions and liquidate in the discretion of its Board based on the level of the Fund's own weekly liquid assets. If a Fund ceases honoring redemptions and determines to liquidate, each Fund expects that it would notify shareholders on the Fund's website. Distributions to shareholders of liquidation proceeds may occur in one or more disbursements.

For the U.S. Government Fund, Treasury Fund and the Treasury Plus Fund

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;

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c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

The U.S. Government Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. Although the Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

For the ESG Liquid Reserves Fund, ILR Fund, Treasury Fund and Treasury Plus Fund

Each of the Treasury Fund and Treasury Plus Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. With respect to the ESG Liquid Reserves Fund, ILR Fund, Treasury Fund and Treasury Plus Fund, the right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed beyond 7 days in accordance with Section 22(e) of the 1940 Act and the rules thereunder, including during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or if an emergency exists as a result of which disposal by the Fund of securities owned by it is not reasonably practicable or it is not reasonably practicable for the Fund fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of shareholders of the Funds. Although each of the Treasury Fund and the Treasury Plus Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption. The ESG Liquid Reserves Fund also may permanently suspend redemptions and liquidate if, among other reasons, (i) the ESG Liquid Reserves Fund, at the end of a business day, has invested less than 10% of its total assets in weekly liquid assets and (ii) the Board, including the Independent Trustees, irrevocably has approved the liquidation of the ESG Liquid Reserves Fund.

For All Funds

A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Funds reserve the right to modify minimum account requirements at any time with or without prior notice. The Funds also reserve the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Funds will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Funds calculate their NAVs earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Funds may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of a Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Currently, exchanging shares is allowed from/to the Treasury Plus Fund, U.S. Government Fund, and Treasury Fund. Exchanges may be made between different Funds within the same class (i.e. Bancroft Capital Class shares for Bancroft Capital Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

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An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

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Financial Intermediary Arrangements

Payments to Financial Intermediaries

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Third-Party Transactions. The State Street Funds have authorized certain Financial Intermediaries to accept purchase, redemption and exchange orders on the State Street Funds' behalf. Orders received for a State Street Fund by a Financial Intermediary that has been authorized to accept orders on the Fund's behalf (or other Financial Intermediaries designated by the Financial Intermediary) will be deemed accepted by the Fund at the time they are received by the Financial Intermediary and will be priced based on the Fund's next NAV determination as long as the Financial Intermediary transmits the order in good form and in a timely manner to the applicable State Street Fund(s). For the ESG Liquid Reserves Fund and ILR Fund, the State Street Funds will be the sole party to determine if a trade is received in good order. The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to a Fund.

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Financial Highlights

The financial highlight tables are intended to help you understand each Fund's financial performance. Certain information reflects the performance results for a single Fund Share. The total returns in the tables represent the rate that an investor would have earned (or lost) on an investment in each Fund (assuming reinvestment of all dividends and distributions). This information has been audited by Ernst & Young LLP, the Trust's independent registered public accounting firm, whose report, along with each Fund's financial highlights and financial statements, is included in the annual report to shareholders, which is available upon request.

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET ESG LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Bancroft Capital Class (a)
	For the Period 10/13/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)
Net realized and unrealized gain (loss)	—
Total from investment operations	0.0000(b)
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$0.9999
Total return (c)	(0.00)%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.18%(e)
Net expenses	0.12%(e)
Net investment income (loss)	0.04%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Bancroft Capital Class (a)
	For the Period 10/13/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)
Net realized and unrealized gain (loss)	(0.0001)
Total from investment operations	(0.0001)
Distributions to shareholders from:
Net investment income	(0.0000)(b)
Net asset value, end of period	$0.9999
Total return (c)	(0.01)%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(d)
Net expenses	0.15%(d)
Net investment income (loss)	0.01%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Bancroft Capital Class (a)
	For the Period 10/13/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0001
Total from investment operations	0.0002
Distributions to shareholders from:
Net investment income	(0.0001)
Net realized gains	(0.0001)
Total distributions	(0.0002)
Net asset value, end of period	$1.0000
Total return (b)	0.00%(c)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(d)
Net expenses	0.05%(d)
Net investment income (loss)	0.01%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Amount is less than 0.005%.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Bancroft Capital Class (a)
	For the Period 10/13/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.00%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(e)
Net expenses	0.05%(e)
Net investment income (loss)	0.02%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Bancroft Capital Class (a)
	For the Period 10/13/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.01%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$100
Ratios to Average Net Assets:
Total expenses	0.14%(d)
Net expenses	0.04%(d)
Net investment income (loss)	0.03%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSIITBANCROFT PRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

This prospectus is intended for use only by clients of Blaylock Van, LLC.

State Street Institutional
Investment Trust

State Street Institutional Treasury Plus Money Market Fund

Blaylock Van Class (BVYXX)

State Street Institutional U.S. Government Money Market Fund

Blaylock Van Class (BUYXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Blaylock Van Class Shares of the applicable Funds.

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Fund Summaries	4
State Street Institutional Treasury Plus Money Market Fund	4
State Street Institutional U.S. Government Money Market Fund	9
Additional Information About Investment Objectives, Principal Strategies and Risks	15
Additional Information About Non-Principal Investment Strategies and Risks	21
Portfolio Holdings Disclosure	23
Management and Organization	24
Shareholder Information	26
Dividends, Distributions and Tax Considerations	31
Financial Intermediary Arrangements	33
Financial Highlights	35

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Blaylock Van Class shares are new. Returns of the Blaylock Van Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Blaylock Van Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.02%		1.01%		0.52%		10/24/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Blaylock Van Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Blaylock Van, LLC and its affiliates.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Blaylock Van Class shares are new. Returns of the Blaylock Van Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Blaylock Van Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2013)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.03%		1.02%		0.54%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Blaylock Van Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Blaylock Van, LLC and its affiliates.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

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By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the Treasury Plus Fund and U.S. Government Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•

Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;

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•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

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Repurchase Agreement Risk. A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund, which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

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U.S. Treasury Obligations Risk. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of a Fund's U.S. Treasury obligations to decline. The total public debt of the United States as a percent of gross domestic product grew rapidly after the financial crisis of 2008 and has remained at a historically high level. Although high debt levels do not necessarily indicate or cause economic problems, they may create certain systemic risks if sound debt management practices are not implemented. A high national debt level may increase market pressures to meet government funding needs, which may drive debt cost higher and cause a country to sell additional debt, thereby increasing refinancing risk. A high national debt also raises concerns that a government will not be able to make principal or interest payments when they are due. In the worst case, unsustainable debt levels can cause a decline in the value of the dollar (which may lead to inflation), and can prevent the U.S. government from implementing effective counter-cyclical fiscal policy in economic downturns. On August 5, 2011, Standard & Poor's Ratings Services downgraded U.S. Treasury securities from AAA rating to AA+ rating. Standard & Poor's Ratings Services stated that its decision was prompted by its view on the rising public debt burden and its perception of greater policymaking uncertainty. A downgrade of the ratings of U.S. government debt obligations, which are often used as a benchmark for other borrowing arrangements, could result in higher interest rates for individual and corporate borrowers, cause disruptions in the international bond markets and have a substantial negative effect on the U.S. economy. A downgrade of U.S. Treasury securities from another ratings agency or a further downgrade below AA+ rating by Standard & Poor's Ratings Services may cause the value of the Fund's U.S. Treasury obligations to decline. In recent years, impasses in Congress regarding the federal budget have caused repeated temporary Federal government shutdowns. While Congress has temporarily suspended the debt limit from time to time, the risks that the U.S. government will not adopt a long-term budget or deficit reduction plan, of one or more additional Federal government shutdowns or of future failures to not increase the Federal government's debt limit, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

Additional Information About Non-Principal Investment Strategies and Risks

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Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Funds, the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such third-party service providers may have limited indemnification obligations to the Adviser or the Funds. Similar types of cybersecurity risks or technical malfunctions also are present for issuers of securities in which each Fund invests, which could result in material adverse consequences for such issuers, and may cause a Fund's investment in such securities to lose value.

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Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.05% for Treasury Plus Portfolio and 0.05% for U.S. Government Portfolio.

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distribution channels could give the Adviser an incentive to implement the Voluntary Reduction for some Funds or share classes and not others, or to implement it to a greater degree for some Funds or share classes than others. Under an agreement with the Service Providers relating to the Voluntary Reduction, the Funds and the Portfolios have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from a Fund.

A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one-day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement), which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class. Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

Additional Information

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Shareholder Information

Determination of Net Asset Value

The Treasury Plus Fund and the U.S. Government Fund each determines its NAV per share once each Business Day at 5:00 p.m. ET except for days when the NYSE closes earlier than its regular closing time, in which event those Funds will determines their NAVs at the earlier closing time. The Funds seek to maintain a $1.00 per share NAV and, accordingly, uses the amortized cost valuation method, in compliance with the risk limiting conditions of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”), to value its portfolio instruments. The amortized cost valuation method initially prices an instrument at its cost and thereafter assumes a constant amortization to maturity of any discount or premium, regardless of the impact of fluctuating interest rates on the market value of the instrument.

Investing in State Street Institutional Investment Trust Shares

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Purchasing Shares

The Funds offer one class of shares through this Prospectus: Blaylock Van Class is available to you subject to the eligibility requirements set forth below. The Fund's Blaylock Van Class is offered only to clients of Blaylock Van, LLC and its affiliates (collectively, Blaylock Clients). The Blaylock Van Class may not be purchased directly from the Funds. Instead Blaylock Clients may purchase the Blaylock Van Class shares through accounts maintained with Blaylock Van, LLC or its affiliates. Blaylock Van, LLC may impose policies, limitations and fees, which are different than those described herein. All classes of a Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. You should choose the class with the expense structure that best meets your needs for which you are eligible. In choosing a share class, you should consider the amount you plan to invest. Your investment professional can help you choose the share class that best suits your investment needs.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their family. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

	Blaylock Van Class
Minimum Initial Investment	$25,000,000
Maximum Investment	None.
Initial Sales Charge	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No.
Distribution and/or Service (12b-1) Fees	No.
Redemption Fees	No.

Investors pay no sales load to invest in the shares of the Funds. The price for Fund Shares is the NAV per share.

The minimum initial investment in Blaylock Van Class shares of the Funds is $25 million, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include but are not limited to accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Funds and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below). The Funds require prior notification of subsequent investments in excess of $50 million.

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How to Purchase Shares

By Mail:

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form.

For the U.S. Government Fund, and the Treasury Plus Fund

If the Treasury Plus Fund or the U.S. Government Fund receives a redemption order in good form prior to 5:00 p.m. ET on a Business Day, the Fund typically expects to pay out redemption proceeds on that day, but no later than the next Business Day if redemption proceeds are sent by wire or ACH. If redemption proceeds are sent by check, the Fund typically expects to pay out redemption proceeds on the next Business Day. No dividends will be paid on shares that are redeemed and wired the same day.

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If redemption proceeds are sent by check, the Fund pays out redemption proceeds on the next Business Day. If a full redemption order is requested, no dividends will accrue with respect to shares on the day the redemption proceeds are sent. If a redemption order is placed after 5:00 p.m. ET, the Fund typically expects to pay out redemption proceeds on the next Business Day (and dividends will accrue up to, but not including, the day that redemption proceeds are sent), but no later than the following Business Day. The Fund may postpone and/or suspend redemption and payment beyond the foregoing time periods only as follows:

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;
c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

The Treasury Plus Fund and the U.S. Government Fund are government money market funds that have not elected to be subject to the fees and gates provisions of Rule 2a-7. Although the Funds attempts to maintain their NAV at $1.00 per share, there can be no assurance that they will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption.

For Each Fund

A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Funds reserve the right to modify minimum account requirements at any time with or without prior notice. The Funds also reserve the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Funds will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Funds calculate their NAVs earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Funds may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of a Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Currently, exchanging shares is allowed from/to the Treasury Plus Fund and U.S. Government Fund. Exchanges may be made between different Funds within the same class (i.e. Blaylock Van Class shares for Blaylock Van Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

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An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

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Financial Intermediary Arrangements

Payments to Financial Intermediaries

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Third-Party Transactions. The State Street Funds have authorized certain Financial Intermediaries to accept purchase, redemption and exchange orders on the State Street Funds' behalf. Orders received for a State Street Fund by a Financial Intermediary that has been authorized to accept orders on the Fund's behalf (or other Financial Intermediaries designated by the Financial Intermediary) will be deemed accepted by the Fund at the time they are received by the Financial Intermediary and will be priced based on the Fund's next NAV determination as long as the Financial Intermediary transmits the order in good form and in a timely manner to the applicable State Street Fund(s). The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to a Fund.

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Financial Highlights

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Blaylock Van Class (a)
	For the Period 10/20/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.00%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$500
Ratios to Average Net Assets:
Total expenses	0.15%(e)
Net expenses	0.05%(e)
Net investment income (loss)	0.01%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Blaylock Van Class (a)
	For the Period 10/20/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.01%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$500
Ratios to Average Net Assets:
Total expenses	0.14%(d)
Net expenses	0.04%(d)
Net investment income (loss)	0.03%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of their respective Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSIITBLAYLOCK PRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

Prospectus

April 30, 2022

This prospectus is intended for use only by clients of Cabrera Capital Markets, LLC.

State Street Institutional
Investment Trust

State Street ESG Liquid Reserves Fund

Cabrera Capital Markets Class (CLFXX)

State Street Institutional Treasury Money Market Fund

Cabrera Capital Markets Class (CSJXX)

State Street Institutional Treasury Plus Money Market Fund

Cabrera Capital Markets Class (CAJXX)

State Street Institutional U.S. Government Money Market Fund

Cabrera Capital Markets Class (CAHXX)

The U.S. Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

An investment in any of the Funds offered by this Prospectus is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Each Fund may offer multiple classes of shares. This Prospectus covers only the Cabrera Capital Markets Class Shares of the applicable Funds.

State Street ESG Liquid Reserves Fund is a “floating net asset value” money market fund. The share price of this Fund will fluctuate.

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Fund Summaries	1
State Street ESG Liquid Reserves Fund	1
State Street Institutional Treasury Money Market Fund	9
State Street Institutional Treasury Plus Money Market Fund	14
State Street Institutional U.S. Government Money Market Fund	19
Additional Information About Investment Objectives, Principal Strategies and Risks	25
Additional Information About Non-Principal Investment Strategies and Risks	37
Portfolio Holdings Disclosure	38
Management and Organization	39
Shareholder Information	41
Dividends, Distributions and Tax Considerations	48
Financial Intermediary Arrangements	50
Financial Highlights	52

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State Street ESG Liquid Reserves Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.13%
Total Annual Fund Operating Expenses	0.18%
Less Fee Waivers and/or Expense Reimbursements²	(0.03%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

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account the effect of any current contractual fee waivers and/or reimbursements; and the calculation of costs for the remaining periods takes such fee waivers and/or reimbursements into account only for the first year of each such period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 year		3 years		5 years		10 years
$15		$55		$98		$227

Principal Investment Strategies

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Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Non-U.S. Securities Risk: Non-U.S. securities (including depositary receipts) are subject to political, regulatory, and economic risks not present in domestic investments. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, legal and financial report standards comparable to those in the United States. Further, such entities and/or their securities may be subject to risks associated with currency controls; expropriation; changes in tax policy; greater market volatility; differing securities market structures; higher transaction costs; and various administrative difficulties, such as delays in clearing and settling portfolio transactions or in receiving payment of dividends. Securities traded on foreign markets may be less liquid (harder to sell) than securities traded domestically. Foreign governments may impose restrictions on the repatriation of capital to the U.S. In addition, to the extent investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Investments in depositary receipts may be less liquid and more volatile than the underlying shares in their primary trading market.

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Performance

The bar chart and table below provide some indication of the risks of investing in the ESG Liquid Reserves Fund by illustrating the variability of the Fund's returns from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Cabrera Capital Markets Class shares are new. Returns of the Cabrera Capital Markets Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Cabrera Capital Markets Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.27% (Q2, 2020)
Lowest Quarterly Return: 0.01% (Q4, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Since Inception		Inception Date
Premier Class		0.07%		0.39%		12/3/2019

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Cabrera Capital Markets Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Cabrera Capital Markets, LLC and its affiliates.

To open an account with the Fund, contact Cabrera Capital Markets LLC by telephone (312-236-8888) or by e-mail at mminfo@cabreracapital.com.

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You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

Principal Risks

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Cabrera Capital Markets Class shares are new. Returns of the Cabrera Capital Markets Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Cabrera Capital Markets Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.57% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q1, 2012)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.01%		1.00%		0.52%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Cabrera Capital Markets Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Cabrera Capital Markets, LLC and its affiliates.

To open an account with the Fund, contact Cabrera Capital Markets LLC by telephone (312-236-8888) or by e-mail at mminfo@cabreracapital.com.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional Treasury Plus Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

Principal Risks

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Performance

The bar chart and table below provide some indication of the risks of investing in the Treasury Plus Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Cabrera Capital Markets Class shares are new. Returns of the Cabrera Capital Markets Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Cabrera Capital Markets Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2021)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.02%		1.01%		0.52%		10/24/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Cabrera Capital Markets Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Cabrera Capital Markets, LLC and its affiliates.

To open an account with the Fund, contact Cabrera Capital Markets LLC by telephone (312-236-8888) or by e-mail at mminfo@cabreracapital.com.

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You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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State Street Institutional U.S. Government Money Market Fund

Investment Objective

Fees and Expenses of the Fund

Shareholder Fees (fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the sale proceeds or the original offering price)	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fee	0.05%
Distribution and/or Shareholder Service (12b-1) Fees	0.00%
Other Expenses¹	0.10%
Total Annual Fund Operating Expenses²	0.15%

¹	Other Expenses are based on estimates for the current fiscal year.

Example:

1 year		3 years		5 years		10 years
$15		$48		$85		$192

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Principal Investment Strategies

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Principal Risks

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Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors, including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

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Performance

The bar chart and table below provide some indication of the risks of investing in the U.S. Government Fund by illustrating the variability of the Fund's returns for Premier Class shares from year-to-year. The historical returns of Premier Class shares, which are not offered in this prospectus, are shown since Cabrera Capital Markets Class shares are new. Returns of the Cabrera Capital Markets Class shares would have been similar to the returns shown for Premier Class because each share class is invested in the same portfolio of securities. Returns would differ only to the extent that the new share class does not have the same expenses as Premier Class shares. Cabrera Capital Markets Class shares are expected to incur higher expenses, and have lower returns, than Premier Class shares. The Fund's past performance does not necessarily indicate how the Fund will perform in the future. Current performance information for the Fund is available toll free by calling (877) 521-4083 or by visiting our website at www.ssga.com/cash.

Annual Total Returns (years ended 12/31)

Highest Quarterly Return: 0.58% (Q2, 2019)
Lowest Quarterly Return: 0.00% (Q3, 2013)

Average Annual Total Returns (for periods ended 12/31/21)

		One Year		Five Years		Ten Years		Inception Date
Premier Class		0.03%		1.02%		0.54%		10/25/2007

To obtain the Fund's current yield, please call (877) 521-4083.

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Purchase and Sale of Fund Shares

Purchase Minimums

Cabrera Capital Markets Class
To establish an account	$25,000,000
To add to an existing account	No minimum

You may purchase or redeem Fund Shares on any day the Fund is open for business.

This prospectus is intended for use only by clients of Cabrera Capital Markets, LLC and its affiliates.

To open an account with the Fund, contact Cabrera Capital Markets LLC by telephone (312-236-8888) or by e-mail at mminfo@cabreracapital.com.

You may purchase or redeem Fund Shares by written request or wire transfer. Written requests should be sent to:

By Mail:

State Street Funds
P.O. Box 219737
Kansas City, MO 64121-9737

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By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone:

By Intermediary:

Financial Intermediaries may contact DST Asset Manager Solutions, Inc. at (877) 332-6207 or via email at nsccresearch@dstsystems.com with questions.

Tax Information

Payments to Broker-Dealers and Other Financial Intermediaries

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Additional Information About Investment Objectives, Principal Strategies and Risks

Investment Objective

The investment objective of each of the ESG Liquid Reserves Fund, Treasury Fund, Treasury Plus Fund and U.S. Government Fund, as stated in each Fund's Summary, may be changed without shareholder approval.

ESG Liquid Reserves Fund

Principal Investment Strategies

The Adviser intends to consider ESG criteria at the time of purchase by using an ESG-related metric for each Fund investment. For most Fund investments, the Adviser uses a proprietary scoring system developed by SSGA that assigns an ESG rating, in the form of a “Responsibility” or “R-Factor^TM” score, to the issuer. The amount of the Fund's investments assigned an R-Factor^TM score will vary from time to time and can change significantly. The R-Factor^TM score measures the performance of a company's business operations and governance as related to financially material ESG challenges facing the issuer's industry. For example, for companies in the asset management industry, the R- FactorTM score currently uses metrics based on selling practices and product labeling, employee engagement / diversity and inclusion, product design and lifecycle management, business ethics, and systemic risk management. The R-Factor^TM score for each applicable issuer draws on a number of data sources, including third-party data providers, that provide metrics on a variety of ESG topics.

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Treasury Fund

Principal Investment Strategies

The Treasury Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government). The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

Treasury Plus Fund

Principal Investment Strategies

The Treasury Plus Fund is a government money market fund and attempts to meet its investment objective by investing only in U.S. Treasury bills, notes and bonds (which are direct obligations of the U.S. government) and repurchase agreements collateralized by these obligations. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

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U.S. Government Fund

Principal Investment Strategies

The U.S. Government Fund is a government money market fund and invests only in obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, as well as repurchase agreements secured by such instruments. The Fund will provide shareholders with at least 60 days' prior notice of any change in this investment policy. The Fund may hold a portion of its assets in cash pending investment, to satisfy redemption requests or to meet the Fund's other cash management needs.

The Fund follows a disciplined investment process that attempts to provide stability of principal, liquidity and current income, by investing in U.S. government securities. Among other things, SSGA FM conducts its own credit analyses of potential investments and portfolio holdings, and relies substantially on a dedicated short-term credit research team. The Fund invests in accordance with regulatory requirements applicable to money market funds. Regulations require, among other things, a money market fund to invest only in short-term, high quality debt obligations (generally, securities that have remaining maturities of 397 calendar days or less, with the exception of certain floating rate securities that may have final maturities longer than 397 days but use maturity shortening provisions to meet the 397 day requirement, and that the Fund believes present minimal credit risk), to maintain a maximum dollar-weighted average maturity and dollar-weighted average life of sixty (60) days or less and 120 days or less, respectively, and to meet requirements as to portfolio diversification and liquidity. All securities held by the Fund are U.S. dollar-denominated, and they may have fixed, variable or floating interest rates.

The Fund attempts to meet its investment objective by investing in:

•	Obligations issued or guaranteed as to principal and/or interest, as applicable, by the U.S. government or its agencies and instrumentalities, such as U.S. Treasury securities and securities issued by the Government National Mortgage Association (“GNMA”), which are backed by the full faith and credit of the United States;
•	Obligations issued or guaranteed by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and U.S. government-sponsored entities such as the Federal Home Loan Bank, and the Federal Farm Credit Banks Funding Corporation, which are not backed by the full faith and credit of the United States; and
•	Repurchase agreements collateralized by U.S. government securities.

Additional Information About Risks

Banking Companies Risk (principal risk for the ESG Liquid Reserves Fund). The performance of bank stocks may be affected by extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, and the interest rates and fees they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds, and can fluctuate significantly when interest rates change. Credit losses resulting from financial difficulties of borrowers can negatively impact the banking companies. Banks may also be subject to severe price competition. Competition among banking companies is high and failure to maintain or increase market share may result in lost market value.

Call/Prepayment Risk (principal risk for the ESG Liquid Reserves Fund). Call/prepayment risk is the risk that an issuer will exercise its right to pay principal on an obligation held by a Fund earlier than expected or required. This may occur, for example, when there is a decline in interest rates, and an issuer of bonds or preferred stock redeems the bonds or stock in order to replace them with obligations on which it is required to pay a lower interest or dividend rate. It may also

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occur when there is an unanticipated increase in the rate at which mortgages or other receivables underlying mortgage- or asset-backed securities held by a Fund are prepaid. In any such case, a Fund may be forced to invest the prepaid amounts in lower-yielding investments, resulting in a decline in the Fund's income.

Counterparty Risk (principal risk for the ESG Liquid Reserves Fund, Treasury Plus Fund and U.S. Government Fund). A Fund will be subject to credit risk with respect to the counterparties with which a Fund enters into repurchase agreements and other transactions. If a counterparty fails to meet its contractual obligations, a Fund may be unable to terminate the transaction, and it may be delayed or prevented from realizing on any collateral in the event of a bankruptcy or insolvency proceeding relating to the counterparty.

Credit Risk (principal risk for the ESG Liquid Reserves Fund, Treasury Plus Fund). Credit risk is the risk that an issuer, guarantor or liquidity provider of a fixed-income security held by a Fund may be unable or unwilling, or may be perceived (whether by market participants, ratings agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. It includes the risk that the security will be downgraded by a credit rating agency; generally, lower credit quality issuers present higher credit risks. An actual or perceived decline in creditworthiness of an issuer of a fixed-income security held by a Fund may result in a decrease in the value of the security. It is possible that the ability of an issuer to meet its obligations will decline substantially during the period when a Fund owns securities of the issuer or that the issuer will default on its obligations or that the obligations of the issuer will be limited or restructured.

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for other funds. The Fund will seek to identify companies that it believes meet its ESG criteria based on the data provided by third parties. The data provided by third parties may be incomplete, inaccurate or unavailable, which could cause the Adviser to incorrectly assess a company's ESG practices. The Fund may invest in companies that do not reflect the beliefs and values of any particular investor.

Extension Risk (principal risk for the ESG Liquid Reserves Fund). During periods of rising interest rates, the average life of certain types of securities may be extended because of slower-than-expected principal payments. This may increase the period of time during which an investment earns a below-market interest rate, increase the security's duration and reduce the value of the security. Extension risk may be heightened during periods of adverse economic conditions generally, as payment rates decline due to higher unemployment levels and other factors.

Financial Institutions Risk (principal risk for the ESG Liquid Reserves Fund). Some instruments are issued or guaranteed by financial institutions, such as banks and brokers, or are collateralized by securities issued or guaranteed by financial institutions. Changes in the creditworthiness of any of these institutions may adversely affect the values of instruments of issuers in financial industries. Financial institutions may be particularly sensitive to certain economic factors such as interest rate changes, adverse developments in the real estate market, fiscal and monetary policy and general economic cycles. Adverse developments in banking and other financial industries may cause a Fund to underperform relative to other funds that invest more broadly across different industries or have a smaller exposure to financial institutions. Changes in governmental regulation and oversight of financial institutions may have an adverse effect on the financial condition or the earnings or operations of a financial institution and on the types and amounts of businesses in which a financial institution may engage. An investor may be delayed or prevented from exercising certain remedies against a financial institution. The amount of a Fund's assets that may be invested in any financial institution, or financial institutions generally, may be limited by applicable law.

Income Risk (principal risk for the ESG Liquid Reserves Fund, and U.S. Government Fund). A Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by a Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by a Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates. A reduction in the income earned by a Fund may limit the Fund's ability to achieve its objective.

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could adversely affect the ability of a Portfolio to conduct its investment program. For example, they could require a Portfolio to sell portfolio securities or purchase portfolio securities unexpectedly and incur substantial transaction costs and/or accelerate the realization of taxable income and/or gains to investors, or a Portfolio may be required to sell its more liquid portfolio investments to meet a large redemption, in which case a Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. A Portfolio may hold a relatively large proportion of its assets in cash in anticipation of large redemptions, diluting its investment returns.

Liquidity Risk (principal risk for the ESG Liquid Reserves Fund). Liquidity risk is the risk that a Fund may not be able to dispose of investments readily at a favorable time or prices (or at all) or at prices approximating those at which a Fund currently values them. For example, certain investments may be subject to restrictions on resale, may trade in the over-the-counter market or in limited volume, or may not have an active trading market. Illiquid investments may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. It may be difficult for a Fund to value illiquid investments accurately. The market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Disposal of illiquid investments may entail registration expenses and other transaction costs that are higher than those for liquid investments. A Fund may seek to borrow money to meet its obligations (including, among other things, redemption obligations) if it is unable to dispose of illiquid investments, resulting in borrowing expenses and possible leveraging of the Fund. In some cases, due to unanticipated levels of illiquidity a Fund may choose to meet its redemption obligations wholly or in part by distributions of assets in-kind.

Market Disruption and Geopolitical Risk. A Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. War, terrorism, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, natural and environmental disasters, pandemics and epidemics, and systemic market dislocations may be highly disruptive to economies and markets. Those events, as well as other changes in foreign and domestic economic and political conditions, also could adversely affect individual issuers or related groups of issuers, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of a Fund's investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region might adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any partial or complete dissolution of the Economic and Monetary Union of the European Union, or any increased uncertainty as to its status, could have significant adverse effects on currency and financial markets, and on the values of a Fund's investments. At a referendum in June 2016, the United Kingdom (the “U.K.”) voted to leave the European Union (“EU”) thereby initiating the British exit from the EU (commonly known as “Brexit”). In March 2017, the U.K. formally notified the European Council of the U.K.'s intention to withdraw from the EU pursuant to Article 50 of the Treaty on European Union. This formal notification began a multi-year period of negotiations regarding the terms of the U.K.'s exit from the EU, which formally occurred on January 31, 2020. The U.K. entered into a transition period where it remained subject to EU rules but had no role in the EU law-making process. During this transition period, U.K. and EU representatives negotiated the terms of their future relationship. The transition period concluded on December 31, 2020 and the U.K. left the EU single market and customs union under the terms of a new trade agreement. The agreement governs the new relationship between the U.K. and EU with respect to trading goods and services but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. There is still considerable uncertainty relating to the potential consequences associated with the exit including whether the U.K.'s exit will increase the likelihood of other countries also departing the EU. Brexit may have a significant impact on the U.K., Europe, and global economies, which may result in increased volatility and illiquidity, new legal and regulatory uncertainties and potentially lower economic growth for these economies that could potentially have an adverse effect on the value of the Portfolios' investments. Securities and financial markets may be susceptible to market manipulation or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the values of investments traded in these markets, including investments held by a Fund. To the extent a Fund has focused its investments in the market or index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

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Money Market Risk-Floating NAV (principal risk for the ESG Liquid Reserves Fund). The Fund does not maintain a constant net asset value per share. The value of the Fund's Shares is calculated to four decimal places and will vary reflecting the value of the portfolio of investments held by the Fund. It is possible to lose money by investing in the Fund.

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Mortgage-Related and Other Asset-Backed Securities Risk (principal risk for the ESG Liquid Reserves Fund and U.S. Government Fund). Investments in mortgage-related and other asset-backed securities are subject to the risk of significant credit downgrades, illiquidity, and defaults to a greater extent than many other types of fixed income investments. The liquidity of mortgage-related and asset-backed securities may change over time. Mortgage-related securities represent a participation in, or are secured by, mortgage loans. Other asset-backed securities are typically structured like mortgage-related securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include, for example, items such as motor vehicle installment sales or installment loan contracts, leases on various types of real and personal property, and receivables from credit card agreements. During periods of falling interest rates, mortgage-related and other asset-backed securities, which typically provide the issuer with the right to prepay the security prior to maturity, may be prepaid, which may result in a Fund having to reinvest the proceeds in other investments at lower interest rates. During periods of rising interest rates, the average life of mortgage-related and other asset-backed securities may extend because of slower-than expected principal payments. This may lock in a below market interest rate, increase the security's duration and interest rate sensitivity, and reduce the value of the security. As a result, mortgage-related and other asset-backed securities may have less potential for capital appreciation during periods of declining interest rates than other debt securities of comparable maturities, although they may have a similar risk of decline in market values during periods of rising interest rates. Prepayment rates are difficult to predict and the potential impact of prepayments on the value of a mortgage-related or other asset-backed security depends on the terms of the instrument and can result in significant volatility. The price of a mortgage-related or other asset-backed security also depends on the credit quality and adequacy of the underlying assets or collateral. Mortgage-related or other asset-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) will generally entail greater credit risk than obligations guaranteed by the U.S. government. Defaults on the underlying assets, if any, may impair the value of a mortgage-related or other asset-backed security. For some asset-backed securities in which a Fund invests, such as those backed by credit card receivables, the underlying cash flows may not be supported by a security interest in a related asset. Moreover, the values of mortgage-related and other asset-backed securities may be substantially dependent on the servicing of the underlying asset pools, and are therefore subject to risks associated with the negligence or malfeasance by their servicers and to the credit risk of their servicers. In certain situations, the mishandling of related documentation may also affect the rights of securities holders in and to the underlying collateral. There may be legal and practical limitations on the enforceability of any security interest granted with respect to underlying assets, or the value of the underlying assets, if any, may be insufficient if the issuer defaults.

Non-U.S. Securities Risk (principal risk for the ESG Liquid Reserves Fund). Investments in securities of non-U.S. issuers (including depositary receipts) entail risks not typically associated with investing in securities of U.S. issuers. Similar risks may apply to securities traded on a U.S. securities exchange that are issued by entities with significant exposure to non-U.S. countries. In certain countries, legal remedies available to investors may be more limited than those available

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with regard to U.S. investments. Income and gains with respect to investments in certain countries may be subject to withholding and other taxes. There may be less information publicly available about a non-U.S. entity than about a U.S. entity, and many non-U.S. entities are not subject to accounting, auditing, and financial reporting standards, regulatory framework and practices comparable to those in the United States. The securities of some non-U.S. entities are less liquid and at times more volatile than securities of comparable U.S. entities, and could become subject to sanctions or embargoes that adversely affect a Fund's investment. Non-U.S. transaction costs, such as brokerage commissions and custody costs may be higher than in the U.S. In addition, there may be a possibility of nationalization or expropriation of assets, imposition of currency exchange controls, confiscatory taxation, and diplomatic developments that could adversely affect the values of a Fund's investments in certain non-U.S. countries. Investments in securities of non-U.S. issuers also are subject to foreign political and economic risk not associated with U.S. investments, meaning that political events (civil unrest, national elections, changes in political conditions and foreign relations, imposition of exchange controls and repatriation restrictions), social and economic events (labor strikes, rising inflation) and natural disasters occurring in a country where a Fund invests could cause the Fund's investments in that country to experience gains or losses.

Rapid Changes in Interest Rates. The values of instruments held by a Fund may be adversely affected by rapid changes in interest rates. Rapid changes in interest rates may cause significant requests to redeem Fund Shares, and possibly cause a Fund to sell portfolio securities at a loss to satisfy those requests. Significant losses would negatively affect the NAV per share of the ESG Liquid Reserves Fund and, in the case of the U.S. Government Fund, Treasury Fund and Treasury Plus Fund, could impair the Fund's ability to maintain a stable share price of $1.00.

Reinvestment Risk (principal risk for the ESG Liquid Reserves Fund and U.S. Government Fund). Income from a Fund's portfolio may decline when the Fund invests the proceeds from investment income, sales of portfolio securities or matured, traded or called debt obligations. For instance, during periods of declining interest rates, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, forcing a Fund to reinvest the proceeds in lower-yielding securities. A decline in income received by a Fund from its investments is likely to have a negative effect on the yield and total return of the Fund Shares.

Repurchase Agreement Risk (principal risk for the ESG Liquid Reserves Fund, Treasury Plus Fund and U.S. Government Fund). A repurchase agreement is an agreement to buy a security from a seller at one price and a simultaneous agreement to sell it back to the original seller at an agreed-upon price, typically representing the purchase price plus interest. Repurchase agreements may be viewed as loans made by a Fund, which are collateralized by the securities subject to repurchase. A Fund's investment return on such transactions will depend on the counterparty's willingness and ability to perform its obligations under a repurchase agreement. If a Fund's counterparty should default on its obligations and a Fund is delayed or prevented from recovering the collateral, or if the value of the collateral is insufficient, a Fund may realize a loss.

Restricted Securities Risk (principal risk for the ESG Liquid Reserves Fund). A Fund may hold securities that have not been registered for sale to the public under the U.S. federal securities laws pursuant to an exemption from registration. These securities may be less liquid than securities registered for sale to the general public. The liquidity of a restricted security may be affected by a number of factors, including, among others: (i) the creditworthiness of the issuer; (ii) the frequency of trades and quotes for the security; (iii) the number of dealers willing to purchase or sell the security and the number of other potential purchasers; (iv) dealer undertakings to make a market in the security; (v) the nature of any legal restrictions governing trading in the security; and (vi) the nature of the security and the nature of marketplace trades. There can be no assurance that a liquid trading market will exist at any time for any particular restricted security. Also, restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility.

Risk of Investment in Other Pools (principal risk for the ESG Liquid Reserves Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as

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investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Risks Related to ECDs, ETDs and YCDs (principal risk for the ESG Liquid Reserves Fund). Banks issuing ECDs, ETDs and YCDs are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of foreign issuers also involve risks such as future unfavorable political and economic developments, withholding or other tax, seizures of foreign deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

Section 4(a)(2) Commercial Paper and Rule 144A Securities Risk (principal risk for the ESG Liquid Reserves Fund). A Fund may invest in commercial paper issued in reliance on the private placement exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the “1933 Act”). This commercial paper is commonly called “Section 4(a)(2) paper.” A Fund may also invest in securities that may be offered and sold only to “qualified institutional buyers” under Rule 144A of the 1933 Act (“Rule 144A securities”).

U.S. Government Securities Risk (principal risk for the ESG Liquid Reserves Fund and U.S. Government Fund). U.S. government securities, such as Treasury bills, notes and bonds and mortgage-backed securities guaranteed by the Government National Mortgage Association (“Ginnie Mae”), are supported by the full faith and credit of the United States; others are supported by the right of the issuer to borrow from the U.S. Treasury; others are supported by the discretionary authority of the U.S. government to purchase the agency's obligations; and still others are supported only by the credit of the issuing agency, instrumentality, or enterprise. Although U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and the Federal National Mortgage Association (“Fannie

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Mae”) may be chartered or sponsored by Congress, they are not funded by Congressional appropriations, and their securities are not issued by the U.S. Treasury nor supported by the full faith and credit of the U.S. government. There is no assurance that the U.S. government would provide financial support to its agencies and instrumentalities if not required to do so. In addition, certain governmental entities have been subject to regulatory scrutiny regarding their accounting policies and practices and other concerns that may result in legislation, changes in regulatory oversight and/or other consequences that could adversely affect the credit quality, availability, or investment character of securities issued by these entities. The value and liquidity of U.S. government securities may be affected adversely by changes in the ratings of those securities. Securities issued by the U.S. Treasury historically have been considered to present minimal credit risk. The downgrade in the long-term U.S. credit rating by at least one major rating agency has introduced greater uncertainty about the ability of the U.S. to repay its obligations. A further credit rating downgrade or a U.S. credit default could decrease the value and increase the volatility of a Fund's investments.

Zero-Coupon Bond Risk (principal risk for the ESG Liquid Reserves Fund). Zero-coupon bonds are debt obligations that are generally issued at a discount and payable in full at maturity, and that do not provide for current payments of interest prior to maturity. Zero-coupon bonds usually trade at a deep discount from their face or par values and are subject to greater market value fluctuations from changing interest rates than debt obligations of comparable maturities that make current distributions of interest. When interest rates rise, the values of zero-coupon bonds fall more rapidly than securities paying interest on a current basis, because a Fund is unable to reinvest interest payments at the higher rates.

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Additional Information About Non-Principal Investment Strategies and Risks

Cybersecurity Risk. With the increased use of technologies such as the Internet and the dependence on computer systems to perform business and operational functions, funds (such as the Funds) and their service providers (including the Adviser) may be prone to operational and information security risks resulting from cyber-attacks and/or technological malfunctions. In addition, the global spread of COVID-19 has caused the Funds, the Portfolios and their service providers to implement business continuity plans, including widespread use of work-from-home arrangements. In general, cyber-attacks are deliberate, but unintentional events may have similar effects. Cyber-attacks include, among others, stealing or corrupting data maintained online or digitally, preventing legitimate users from accessing information or services on a website, releasing confidential information without authorization, and causing operational disruption. Successful cyber-attacks against, or security breakdowns of, a Fund, a Portfolio, the Adviser or a custodian, transfer agent, or other affiliated or third-party service provider may adversely affect a Fund or its shareholders. For instance, cyber-attacks or technical malfunctions may interfere with the processing of shareholder or other transactions, affect a Fund's ability to calculate its NAV, cause the release of private shareholder information or confidential Fund information, impede trading, cause reputational damage, and subject a Fund to regulatory fines, penalties or financial losses, reimbursement or other compensation costs, and additional compliance costs. Cyber-attacks or technical malfunctions may render records of Fund assets and transactions, shareholder ownership of Fund Shares, and other data integral to the functioning of a Fund inaccessible or inaccurate or incomplete. A Fund may also incur substantial costs for cybersecurity risk management in order to prevent cyber incidents in the future. A Fund and its shareholders could be negatively impacted as a result. While the Adviser has established business continuity plans and systems designed to minimize the risk of cyber-attacks through the use of technology, processes and controls, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified, given the evolving nature of this threat. Each Fund relies on third-party service providers for many of its day-to-day operations, and will be subject to the risk that the protections and protocols implemented by those service providers will be ineffective to protect the Fund from cyber-attack. The Adviser does not control the cybersecurity plans and systems put in place by third-party service providers, and such

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Risk of Investment in Other Pools (risk for the Treasury Fund, Treasury Plus Fund and U.S. Government Fund). If a Fund invests in another pooled investment vehicle, it is exposed to the risk that the other pool will not perform as expected. A Fund is exposed indirectly to all of the risks applicable to an investment in such other pool. In addition, lack of liquidity in the underlying pool could result in its value being more volatile than the underlying portfolio of securities, and may limit the ability of a Fund to sell or redeem its interest in the pool at a time or at a price it might consider desirable. The investment policies and limitations of the other pool may not be the same as those of the Fund; as a result, the Fund may be subject to additional or different risks, or may achieve a reduced investment return, as a result of its investment in another pool. If a pool is an exchange-traded fund or other product traded on a securities exchange or otherwise actively traded, its shares may trade at a premium or discount to their NAV, an effect that might be more pronounced in less liquid markets. A Fund bears its proportionate share of the fees and expenses of any pool in which it invests. The Adviser or an affiliate may serve as investment adviser to a pool in which the Fund may invest, leading to potential conflicts of interest. For example, the Adviser or its affiliates may receive fees based on the amount of assets invested in the pool. Investment by a Fund in the pool may be beneficial to the Adviser or an affiliate in the management of the pool, by helping to achieve economies of scale or enhancing cash flows. Due to this and other factors, the Adviser may have an incentive to invest a Fund's assets in a pool sponsored or managed by the Adviser or its affiliates in lieu of investments by the Fund directly in portfolio securities, or may have an incentive to invest in the pool over a pool sponsored or managed by others. Similarly, the Adviser may have an incentive to delay or decide against the sale of interests held by a Fund in a pool sponsored or managed by the Adviser or its affiliates. It is possible that other clients of the Adviser or its affiliates will purchase or sell interests in a pool sponsored or managed by the Adviser or its affiliates at prices and at times more favorable than those at which a Fund does so.

Portfolio Holdings Disclosure

The Funds' portfolio holdings disclosure policy is described in the Statement of Additional Information (“SAI”).

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Management and Organization

Investment Adviser

Each Fund has entered into an investment advisory agreement with the Adviser pursuant to which the Adviser will manage the Fund's assets directly, for compensation paid at an annual rate of 0.05% of the Fund's average daily net assets, in the event that the Fund were to cease investing substantially all of its assets in its corresponding Portfolio or another investment company with essentially the same investment objectives and policies as the Fund. The Adviser does not receive any management fees from a Fund under that agreement so long as the Fund continues to invest substantially all of its assets in the corresponding Portfolio or in another investment company with essentially the same investment objectives and policies as the Fund. The Adviser places all orders for purchases and sales of the Portfolios' investments. For the year ended December 31, 2021, the effective management fee paid, reflecting certain fee waivers and expense reimbursements of the Adviser, was 0.00% for the ESG Liquid Reserves Portfolio, 0.05% for Money Market Portfolio, 0.05% for Treasury Portfolio, 0.05% for Treasury Plus Portfolio and 0.05% for U.S. Government Portfolio.

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the Voluntary Reduction for some Funds, or some share classes of a Fund, and not others. The amount of any Voluntary Reduction may differ between Funds and share classes in the Adviser's sole discretion. The business objectives of the Adviser and its affiliates and their broader relationships with certain Fund shareholders, Financial Intermediaries or distribution channels could give the Adviser an incentive to implement the Voluntary Reduction for some Funds or share classes and not others, or to implement it to a greater degree for some Funds or share classes than others. Under an agreement with the Service Providers relating to the Voluntary Reduction, the Funds and the Portfolios have agreed to reimburse the Service Providers for the full dollar amount of any Voluntary Reduction beginning on May 1, 2020, subject to certain limitations. Each Service Provider may, in its sole discretion, irrevocably waive receipt of any or all reimbursement amounts due from a Fund.

A reimbursement to the Service Provider would increase fund expenses and may negatively impact a Fund's yield during such period. There is no guarantee that the Voluntary Reduction will be in effect at any given time or that a Fund will be able to avoid a negative yield. The Funds have agreed, subject to certain limitations, to reimburse the applicable Service Provider for the full dollar amount of any Voluntary Reduction incurred after May 1, 2020. A Fund is not obligated to reimburse a Service Provider: (1) more than three years after the end of the fiscal year of the Fund in which the Service Provider provided a Voluntary Reduction; (2) in respect of any business day for which the net annualized one-day yield of the Fund or applicable Class is less than 0.00%; (3) to the extent that the amount of the reimbursement to all Service Providers on any day exceeds fifty percent of the yield (net of all expenses, exclusive of the reimbursement) of the Fund or the applicable class on that day; (4) to the extent that the amount of such reimbursement would cause the Fund's or applicable class's net yield to fall below the Fund's or applicable class's minimum yield; (5) in respect of any such fee waivers and/or expense reimbursements that are necessary to maintain the Fund's Contractual Total Expense Limit (as defined in the Reimbursement Agreement), which is effective at the time of such fee waivers and/or expense reimbursements; or (6) in any manner that would result in a class bearing the cost of a reimbursement to the Service Provider for any class-specific expense (including, without limitation, fees payable in accordance with a plan authorized pursuant to Rule 12b-1 under the 1940 Act, or Shareholder Servicing Agreement or similar arrangement) that was waived or reimbursed to the Fund with respect to a different Class.

Any such future reimbursement of an applicable Service Provider may result in the total annual operating expenses with respect to a share class of a Fund exceeding the amount of the expense cap under the contractual expense limitation agreement because the expense is not covered by the agreement.

A discussion regarding the Board's consideration of the Funds' Investment Advisory Agreement is provided in the Funds' Semi-Annual Report to Shareholders for the period ended June 30, 2021.

The Administrator, Sub-Administrator and Custodian

The Adviser serves as administrator of each Fund. The amount of the fee paid to the Adviser for administrative services may vary by share class. Each Fund currently pays the Adviser an administrative fee at the annual rate of 0.05% in respect of the class of shares in this Prospectus. State Street Bank and Trust Company (“State Street”), a subsidiary of State Street Corporation, serves as the sub-administrator for the Funds for a fee that is paid by the Adviser. State Street also serves as custodian of the Funds for a separate fee that is paid by the Funds. SSGA FM serves as administrator of the Portfolios and State Street serves as sub-administrator and custodian of the Portfolios.

The Transfer Agent and Dividend Disbursing Agent

DST Asset Manager Solutions, Inc. is the Funds' transfer agent and dividend disbursing agent (the “Transfer Agent”).

The Distributor

State Street Global Advisors Funds Distributors, LLC serves as the Funds' distributor (“SSGA FD”) pursuant to the Distribution Agreement between SSGA FD and the Trust.

The Shareholder Servicing Agent

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Additional Information

Shareholder Information

Determination of Net Asset Value

For the ESG Liquid Reserves Fund

The NAV of each class of a Fund's shares is calculated by dividing the value of the assets of the Fund attributable to that class less the liabilities of the Fund attributable to that class by the number of shares in the class outstanding. Each Fund values each security or other investment pursuant to guidelines adopted by the Board. Securities or other investments may be valued at fair value, as determined in good faith and pursuant to procedures approved by the Portfolio's Board, under certain limited circumstances. For example, fair value pricing may be used when market quotations are not readily available or reliable, such as when (i) trading for a security is restricted; or (ii) a significant event, as determined by the Adviser, that may affect the value of one or more securities or other investments held by a Fund occurs after the close of a related exchange but before the determination of the Fund's NAV. Attempts to determine the fair value of securities or other investments introduce an element of subjectivity to the pricing of securities or other investments. As a result, the price of a security or other investment determined through fair valuation techniques may differ from the price quoted or published by other sources and may not accurately reflect the price a Fund would have received had it sold the investment. To the extent that a Fund invests in the shares of other registered open-end investment companies that are not traded on an exchange (mutual funds), such shares are valued at their published net asset values per share as reported by the funds. The prospectuses of these funds explain the circumstances under which the funds will use fair value pricing and the effects of using fair value pricing.

For the U.S. Government Fund, Treasury Plus Fund and Treasury Fund

For all Funds

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Investing in State Street Institutional Investment Trust Shares

Purchasing Shares

The Funds offer one class of shares through this Prospectus: Cabrera Capital Markets Class is available to you subject to the eligibility requirements set forth below. The Fund's Cabrera Capital Markets Class is offered only to clients of Cabrera Capital Markets, LLC and its affiliates (collectively, Cabrera Clients). The Cabrera Capital Markets Class may not be purchased directly from the Funds. Instead Cabrera Clients may purchase the Cabrera Capital Markets Class shares through accounts maintained with Cabrera Capital Markets, LLC or its affiliates. Cabrera Capital Markets, LLC may impose policies, limitations and fees, which are different than those described herein. All classes of a Fund share the same investment objective and investments, but the different share classes have different expense structures and eligibility requirements. You should choose the class with the expense structure that best meets your needs for which you are eligible. In choosing a share class, you should consider the amount you plan to invest. Your investment professional can help you choose the share class that best suits your investment needs.

The minimum purchase amount may be waived for specific investors or types of investors, including, without limitation, retirement plans, employees of State Street Corporation and its affiliates and their family. In the case of shareholders purchasing shares through a Financial Intermediary, the minimum purchase amount may be applied at the level of the Financial Intermediary.

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	Cabrera Capital Markets Class
Minimum Initial Investment	$25,000,000
Maximum Investment	None.
Initial Sales Charge	No. Entire purchase price is invested in shares of a Fund.
Deferred (CDSC) Sales Charge	No.
Distribution and/or Service (12b-1) Fees	No.
Redemption Fees	No.

Investors pay no sales load to invest in the shares of the Funds. The price for Fund Shares is the NAV per share.

The minimum initial investment in Cabrera Capital Markets Class shares of the Funds is $25 million, although the Adviser may waive the minimum in its discretion. Holdings of related customer accounts may be aggregated for purposes of determining the minimum investment amount. “Related customer accounts” may include but are not limited to accounts held by the same investment or retirement plan, financial institution, broker, dealer or intermediary. The Funds and the Adviser reserve the right to increase or decrease the minimum amount required to open or maintain an account. There is no minimum subsequent investment, except in relation to maintaining certain minimum account balances (See “Redeeming Shares” below). The Funds require prior notification of subsequent investments in excess of $10 million for the Treasury Fund and $50 million for the Treasury Plus Fund and U.S. Government Fund.

The Funds reserve the right to cease accepting investments at any time or to reject any investment order. In addition, the Treasury Plus Fund and U.S. Government Fund may limit the amount of a purchase order received after 3:00 p.m. ET. The Treasury Fund may limit the amount of a purchase order received after 12:00 p.m. (noon) ET. The ESG Liquid Reserves Fund determines its NAV at 8:00 a.m., 12:00 p.m. and 3:00 p.m. ET. The 8:00 a.m., 12:00 p.m. and 3:00 p.m. NAV calculation times are intended to facilitate same day settlement.

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How to Purchase Shares

By Mail:

By Overnight:

State Street Funds
430 W 7^th Street Suite 219737
Kansas City, MO 64105-1407

By Telephone/Fax:

For your initial investment, send the original, signed Institutional Account Application Form to the address above.

Wire Instructions:

Instruct your bank to transfer money by Federal Funds wire to:
State Street Bank and Trust Company
1 Iron Street
Boston, MA 02210

ABA# 011000028
DDA# 9904-631-0
State Street Institutional Investment Trust
Fund Name
Class Name
Account Number
Account Registration

The Funds and the Funds' agents are not responsible for transfer errors by the sending or receiving bank and will not be liable for any loss incurred due to a wire transfer not having been received.

Redeeming Shares

An investor may redeem all or any portion of its investment. Redemption orders are processed at the NAV next determined after a Fund receives a redemption order in good form.

For the ESG Liquid Reserves Fund

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Certain special limitations affecting redemptions. The SEC has implemented a number of requirements, including liquidity fees and redemption gates, for money market funds based on the amount of fund assets in “weekly liquid assets,” which generally includes cash, direct obligations of the U.S. government, certain other U.S. government or agency securities, and securities that will mature or are subject to a demand feature that is exercisable and payable within five Business Days. Each Fund will pass through to its investors any liquidity fee or suspension of redemptions imposed by its corresponding Portfolio on the same terms and conditions as imposed by the Portfolio on the Fund.

If a Portfolio's weekly liquid assets fall below 30% of its total assets and the Portfolio's Board determines it is in the best interests of the Portfolio, the Portfolio may immediately impose a liquidity fee of no more than 2% and/or temporarily suspend redemptions for up to 10 Business Days in any 90 day period. If a Portfolio's weekly liquid assets fall below 10% of its total assets at the end of any Business Day, the Portfolio will impose a liquidity fee of 1% on all redemptions beginning on the next Business Day, unless the Portfolio's Board determines that imposing such a fee would not be in the best interests of the Portfolio or determines that a lower or higher fee (not to exceed 2%) would be in the best interests of the Portfolio, which would remain in effect until weekly liquid assets return to 30% or the Portfolio's Board determines that the fee is no longer in the best interests of the Portfolio. All liquidity fees payable by a Fund would be passed through to its shareholders, would be payable to its corresponding Portfolio and could offset any losses realized by the Portfolio when seeking to honor redemption requests. If liquidity fees are imposed or redemptions are suspended by a Portfolio, the corresponding Fund will notify shareholders on the Fund's website. Each Fund expects to treat such liquidity fees paid to its corresponding Portfolio as reducing proceeds paid to shareholders in redemption of Fund shares, and not constituting income to the Portfolio or the Fund. There may be circumstances under which a Fund may impose its own liquidity fees and/or suspend redemptions based on the level of the Fund's own weekly liquid assets, in which case the Fund will also provide notice to shareholders.

If a Portfolio's weekly liquid assets fall below 10% of its assets on a Business Day, the Portfolio may cease honoring redemptions and liquidate in the discretion of the Portfolio's Board. If a Fund is notified that its corresponding Portfolio's weekly liquid assets fall below 10% of the Portfolio's assets and the Portfolio has suspended redemptions and intends to liquidate, the Fund may also do so in the discretion of the Fund's Board. There may be circumstances under which a Fund may cease honoring redemptions and liquidate in the discretion of its Board based on the level of the Fund's own weekly liquid assets. If a Fund ceases honoring redemptions and determines to liquidate, each Fund expects that it would notify shareholders on the Fund's website. Distributions to shareholders of liquidation proceeds may occur in one or more disbursements.

For the U.S. Government Fund, Treasury Fund and the Treasury Plus Fund

a)	For any period during which there is a non-routine closure of the Fedwire or applicable Federal Reserve Banks;
b)	For any period (1) during which the NYSE is closed other than customary week-end and holiday closings or (2) during which trading on the NYSE is restricted;

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c)	For any period during which an emergency exists as a result of which (1) disposal of securities owned by the Fund is not reasonably practicable or (2) it is not reasonably practicable for the Fund to fairly determine the net asset value of shares of the Fund;
d)	For any period during which the SEC has, by rule or regulation, deemed that (1) trading shall be restricted or (2) an emergency exists;
e)	For any period that the SEC, may by order permit for your protection; or
f)	For any period during which the Fund as part of a necessary liquidation of the fund, has properly postponed and/or suspended redemption of shares and payment in accordance with federal securities laws.

For the ESG Liquid Reserves Fund, Treasury Fund and Treasury Plus Fund

Each of the Treasury Fund and Treasury Plus Fund is a government money market fund that has not elected to be subject to the fees and gates provisions of Rule 2a-7. With respect to the ESG Liquid Reserves Fund, Treasury Fund and Treasury Plus Fund, the right of any investor to receive payment with respect to any redemption may be suspended or the payment of the redemption proceeds postponed beyond 7 days in accordance with Section 22(e) of the 1940 Act and the rules thereunder, including during any period in which the NYSE is closed (other than weekends or holidays) or trading on the NYSE is restricted or if an emergency exists as a result of which disposal by the Fund of securities owned by it is not reasonably practicable or it is not reasonably practicable for the Fund fairly to determine the value of its net assets. In addition, the SEC may by order permit suspension of redemptions for the protection of shareholders of the Funds. Although each of the Treasury Fund and the Treasury Plus Fund attempts to maintain its NAV at $1.00 per share, there can be no assurance that it will be successful, and there can be no assurance that a shareholder will receive $1.00 per share upon any redemption. The ESG Liquid Reserves Fund also may permanently suspend redemptions and liquidate if, among other reasons, (i) the ESG Liquid Reserves Fund, at the end of a business day, has invested less than 10% of its total assets in weekly liquid assets and (ii) the Board, including the Independent Trustees, irrevocably has approved the liquidation of the ESG Liquid Reserves Fund.

For All Funds

A Fund may pay all or a portion of your redemption proceeds by giving you securities (for example, if the Fund reasonably believes that a cash redemption may have a substantial impact on the Fund and its remaining shareholders). You may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of the redemption. In addition, you will be subject to the market risks associated with such securities until such time as you choose to dispose of the security.

A request for a partial redemption by an investor whose account balance is below the minimum amount or a request for partial redemption by an investor that would bring the account below the minimum amount may be treated as a request for a complete redemption of the account. These minimums may be different for investments made through certain financial intermediaries as determined by their policies and may be waived in the Adviser's discretion. The Funds reserve the right to modify minimum account requirements at any time with or without prior notice. The Funds also reserve the right to involuntarily redeem an investor's account if the investor's account balance falls below the applicable minimum amount due to transaction activity.

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How to Redeem Shares


By Mail:	Send a signed letter to: State Street Institutional Investment Trust Funds P.O. Box 219737 Kansas City, MO 64121-9737
	The letter should include information necessary to process your request as described below. The Fund may require a medallion guarantee in certain circumstances. See “Medallion Guarantees” below.
By Overnight:	State Street Institutional Investment Trust Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407
By Telephone:	Please call (866) 392-0869 between the hours of 7:00 a.m. and 5:00 p.m. ET.
The Funds will need the following information to process your redemption request:
➣ name(s) of account owners; ➣ account number(s); ➣ the name of the Fund; ➣ your daytime telephone number; and ➣ the dollar amount or number of shares being redeemed.

On any day that the Funds calculate their NAVs earlier than normal, the Funds reserve the right to adjust the times noted above for purchasing and redeeming shares.

Medallion Guarantees. Certain redemption requests must include a medallion guarantee for each registered account owner if any of the following apply:

•	Your account address has changed within the last 10 Business Days.
•	Redemption proceeds are being transferred to an account with a different registration.
•	A wire is being sent to a financial institution other than the one that has been established on your Fund account.
•	Other unusual situations as determined by the Transfer Agent.

The Funds may terminate the receipt of redemption orders by telephone at any time, in which case you may redeem shares by other means.

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If you choose to purchase or redeem shares by sending instructions by regular mail, they will not be deemed received in good order until they are released by the post office and redelivered to the Transfer Agent's physical location at 430 W 7th Street Suite 219737 in Kansas City, MO 64105-1407. There will be a time lag, which may be one or more days, between regular mail receipt at the post office box and redelivery to such physical location in Kansas City, and a Fund's NAV may change over those days. You might consider using express rather than regular mail if you believe the time of receipt of your transaction request to be sensitive.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of a Fund in the State Street Institutional Investment Trust to simultaneously purchase shares of a different Fund in the State Street Institutional Investment Trust. Currently, exchanging shares is allowed from/to the Treasury Plus Fund, U.S. Government Fund, and Treasury Fund. Exchanges may be made between different Funds within the same class (i.e. Cabrera Capital Markets Class shares for Cabrera Capital Markets Class shares). The account holding the original shares must be registered in the same name as the account holding the new shares received in the exchange. You may make exchange requests by telephone, or by mail. See Purchasing Shares and Redeeming Shares. Exchanges are subject to the terms applicable to the purchases of the fund into which you are exchanging. Exchange privileges may not be available for mutual funds advised by SSGA FM (the “State Street Funds”) and may be suspended or rejected.

Excessive Trading

Delivery of Documents to Accounts Sharing an Address

To reduce expenses, we may mail only one copy of the Funds' Prospectus and each annual and semi-annual report to those addresses shared by two or more accounts. If you wish to receive individual copies of these documents, please call us at (866) 392-0869, or contact your financial institution. We will begin sending you individual copies thirty (30) days after receiving your request.

Unclaimed Property

Many states have unclaimed property rules that provide for transfer to the state (also known as “escheatment”) of unclaimed property under various circumstances. These circumstances include inactivity (e.g., no owner-initiated contact for a certain period), returned mail (e.g., when mail sent to a shareholder is returned by the post office as undeliverable), or a combination of both inactivity and returned mail. If a State Street Fund identifies property as unclaimed, it will attempt to contact the shareholder, but if that attempt is unsuccessful, the account may be considered abandoned and escheated to the state after the passage of a certain period of time (as required by applicable state law).

If you are a resident of the state of Texas, you may designate a representative to receive escheatment notifications by completing and submitting a designation form, which you can find on the website of the Texas Comptroller. Designating such a representative may be beneficial, since Texas law provides that the escheatment period will cease if the representative, after receiving an escheatment notification regarding your account, communicates knowledge of your location and confirms that you have not abandoned your account. You can mail a completed designation form to the Fund (if you hold shares directly with the Fund) or to your financial intermediary (if you do not hold shares directly with the Fund) .

Dividends, Distributions and Tax Considerations

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An additional 3.8% Medicare contribution tax is imposed on the “net investment income” of individuals, estates and trusts to the extent their income exceeds certain threshold amounts. Net investment income generally includes for this purpose dividends paid by a Fund and net gains recognized on the redemption of Fund Shares.

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Financial Intermediary Arrangements

Payments to Financial Intermediaries

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Third-Party Transactions. The State Street Funds have authorized certain Financial Intermediaries to accept purchase, redemption and exchange orders on the State Street Funds' behalf. Orders received for a State Street Fund by a Financial Intermediary that has been authorized to accept orders on the Fund's behalf (or other Financial Intermediaries designated by the Financial Intermediary) will be deemed accepted by the Fund at the time they are received by the Financial Intermediary and will be priced based on the Fund's next NAV determination as long as the Financial Intermediary transmits the order in good form and in a timely manner to the applicable State Street Fund(s). For the ESG Liquid Reserves Fund, the State Street Funds will be the sole party to determine if a trade is received in good order. The Financial Intermediary is responsible for transmitting your orders and associated funds in good form and in a timely manner to the applicable State Street Fund(s). The State Street Funds will not be responsible for delays by the Financial Intermediary in transmitting your orders, including timely transfer of payment, to a Fund.

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Financial Highlights

STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET ESG LIQUID RESERVES FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Cabrera Capital Markets Class (a)
	For the Period 10/20/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0000(b)
Net realized and unrealized gain (loss)	—
Total from investment operations	0.0000(b)
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$0.9999
Total return (c)	(0.00)%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.18%(e)
Net expenses	0.12%(e)
Net investment income (loss)	0.05%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Cabrera Capital Markets Class (a)
	For the Period 10/20/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0001
Total from investment operations	0.0002
Distributions to shareholders from:
Net investment income	(0.0001)
Net realized gains	(0.0001)
Total distributions	(0.0002)
Net asset value, end of period	$1.0000
Total return (b)	0.00%(c)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.15%(d)
Net expenses	0.05%(d)
Net investment income (loss)	0.02%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(c)	Amount is less than 0.005%.
(d)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL TREASURY PLUS MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Cabrera Capital Markets Class (a)
	For the Period 10/20/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.00%(d)
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$50
Ratios to Average Net Assets:
Total expenses	0.13%(e)
Net expenses	0.04%(e)
Net investment income (loss)	0.02%(e)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of the affiliated Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Amount is less than 0.005%.
(e)	Annualized.

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STATE STREET INSTITUTIONAL INVESTMENT TRUST

STATE STREET INSTITUTIONAL U.S. GOVERNMENT MONEY MARKET FUND

FINANCIAL HIGHLIGHTS

Selected data for a share outstanding throughout each period

	Cabrera Capital Markets Class (a)
	For the Period 10/20/21*- 12/31/21
Net asset value, beginning of period	$1.0000
Income (loss) from investment operations:
Net investment income (loss)	0.0001
Net realized gain (loss)	0.0000(b)
Total from investment operations	0.0001
Distributions to shareholders from:
Net investment income	(0.0001)
Total distributions	(0.0001)
Net asset value, end of period	$1.0000
Total return (c)	0.01%
Ratios and Supplemental Data:
Net assets, end of period (in 000s)	$100
Ratios to Average Net Assets:
Total expenses	0.14%(d)
Net expenses	0.04%(d)
Net investment income (loss)	0.02%(d)

*	Commencement of operations.
(a)	The per share amounts and percentages include the Fund's proportionate share of income and expenses of their respective Portfolio.
(b)	Amount is less than $0.00005 per share.
(c)	Total return is calculated assuming a purchase of shares at net asset value on the first day and a sale at net asset value on the last day of each period reported. Distributions are assumed, for the purpose of this calculation, to be reinvested at net asset value per share on the respective payment dates of the Fund. Total return for periods of less than one year are not annualized. Results represent past performance and are not indicative of future results.
(d)	Annualized.

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Contacting the State Street Funds

Online:	www.ssga.com/cash	24 hours a day, 7 days a week
Phone:	(877) 521-4083	Monday – Friday 7:00 am – 5:00 pm EST

Written requests should be sent to:

Regular mail	Overnight/ Registered, Express, Certified Mail
State Street Funds P.O. Box 219737 Kansas City, MO 64121-9737	State Street Funds 430 W 7^th Street Suite 219737 Kansas City, MO 64105-1407

Regular mail / Overnight Registered, Express, Certified Mail

Cabrera Capital Markets
10 S LaSalle Street Suite 1050
Chicago, IL, 60603

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For more information about the Funds:

The Funds' SAI includes additional information about the Funds and is incorporated by reference into this document. Additional information about the Funds' investments is available in the Funds' most recent annual and semi-annual reports to shareholders. The Funds' SAI is available, without charge, upon request. The Funds' annual and semi-annual reports are available, without charge, upon request. Shareholders in the Funds may make inquiries to the Funds to receive such information by calling (877) 521-4083 or the customer service center at the telephone number shown in the accompanying contract prospectus, if applicable. Each Fund's Prospectus and SAI are available, and the annual and semi-annual reports to shareholders are available, free of charge, on the Funds' website at www.ssga.com/cash.

SSGA Funds Management, Inc.

ONE IRON STREET

BOSTON, MASSACHUSETTS 02210

SSIITCABRERA PRO

The State Street Institutional Investment Trust's Investment Company Act File Number is 811-09819.

The SAI is not a prospectus and should be read in conjunction with the Prospectuses. A copy of each Prospectus can be obtained free of charge by calling (877) 521-4083 or by written request to the Trust at the address listed above.

The Trust was organized as a business trust under the laws of The Commonwealth of Massachusetts on February 16, 2000.

The Trust is an open-end management investment company. The Trust includes the following diversified series:

Trust Class shares of the ILR Fund are issued only to former shareholders of SSGA Prime Money Market Fund and SSGA Money Market Fund, each a series of SSGA Funds. Trust Class shares of the Treasury Plus Fund are issued only to former shareholders of SSGA U.S. Treasury Money Market Fund, a series of SSGA Funds.

Each Fund’s Prospectus contains information about the investment objective and policies of that Fund. This SAI should only be read in conjunction with the Prospectus of the Fund or Funds in which you intend to invest.

In addition to the principal investment strategies and the principal risks of the Funds and Portfolios described in each Fund’s Prospectus, a Fund or Portfolio may employ other investment practices and may be subject to additional risks, which are described below. In reviewing these practices of the Feeder Funds, you should assume that the practices of the corresponding Portfolio are the same in all material respects.

To the extent consistent with its investment objective and restrictions, each Fund or Portfolio may invest in the following instruments and use the following techniques, and is subject to the following additional risks.

Auction rate municipal securities permit the holder to sell the securities in an auction at par value at specified intervals. The dividend or interest is typically reset by “Dutch” auction in which bids are made by broker-dealers and other institutions for a certain amount of securities at a specified minimum yield. The rate set by the auction is the lowest interest or dividend rate that covers all securities offered for sale. While this process is designed to permit auction rate securities to be traded at par value, there is the risk that an auction will fail due to insufficient demand for the securities. A Portfolio will take the time remaining until the next scheduled auction date into account for purposes of determining the securities’ duration.

term debt securities rated at the time of purchase Aa or higher by Moody’s Investors Service, Inc. (“Moody’s”) or AA or higher by Standard & Poor’s Rating Group (“S&P”) or, if unrated, of comparable quality in the opinion of SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”); (iii) commercial paper; (iv) bank obligations, including negotiable certificates of deposit, time deposits and bankers’ acceptances; and (v) repurchase agreements.

Counterparty risk with respect to derivatives has been and will continue to be affected by new rules and regulations relating to the derivatives market. With respect to a centrally cleared transaction, a party is subject to the credit risk of the clearing house and the clearing member through which it holds its cleared position. Credit risk of market participants with respect to centrally cleared derivatives is concentrated in a few clearing houses, and it is not clear how an insolvency proceeding of a clearing house would be conducted and what impact an insolvency of a clearing house would have on the financial system. A clearing member is obligated by contract and regulation to segregate all funds received from customers with respect to cleared derivatives positions from the clearing member’s proprietary assets. However, all funds and other property received by a clearing member from its customers with respect to cleared derivatives are generally held by the clearing member on a commingled basis in an omnibus account (which can be invested in instruments permitted under the regulations). Therefore, a Portfolio might not be fully protected in the event of the bankruptcy of the Portfolio’s clearing member because the Portfolio would be limited to recovering only a pro rata share of the funds held by the clearing member on behalf of customers, with a claim against the clearing member for any deficiency. Also, the clearing member is required to transfer to the clearing house the amount of margin required by the clearing house for cleared derivatives, which amount is generally held in an omnibus account at the clearing house for all customers of the clearing member. Regulations promulgated by the Commodity Futures Trading Commission (the “CFTC”) require that the clearing member notify the clearing house of the initial margin provided by the clearing member to the clearing house that is attributable to each customer. However, if the clearing member does not accurately report the Portfolio’s initial margin, the Portfolio is subject to the risk that a clearing house will use the assets attributable to it in the clearing house’s omnibus account to satisfy payment obligations a defaulting customer of the clearing member has to the clearing house. In addition, clearing members generally provide the clearing house the net amount of variation margin required for cleared swaps for all of its customers, rather than individually for each customer. A Portfolio is therefore subject to the risk that a clearing house will not make variation margin payments owed to the Portfolio if another customer of the clearing member has suffered a loss and is in default, and the risk that the Portfolio will be required to provide additional variation margin to the clearing house before the clearing house will move the Portfolio’s cleared derivatives positions to another clearing member. In addition, if a clearing member does not comply with the applicable regulations or its agreement with the Portfolio, or in the event of fraud or misappropriation of customer assets by a clearing member, the Portfolio could have only an unsecured creditor claim in an insolvency of the clearing member with respect to the margin held by the clearing member.

Certain derivatives contracts are required to be executed through swap execution facilities (“SEFs”). A SEF is a trading platform where multiple market participants can execute derivatives by accepting bids and offers made by multiple other participants in the platform. Such requirements may make it more difficult and costly for investment funds, such as a Portfolio, to enter into highly tailored or customized transactions. Trading swaps on a SEF may offer certain advantages over traditional bilateral over-the-counter trading, such as ease of execution, price transparency, increased liquidity and/or favorable pricing. Execution through a SEF is not, however, without additional costs and risks, as parties are required to comply with SEF and CFTC rules and regulations, including disclosure and recordkeeping obligations, and SEF rights of inspection, among others. SEFs typically charge fees, and if a Portfolio executes derivatives on a SEF through a broker intermediary, the intermediary may impose fees as well. A Portfolio also may be required to indemnify a SEF, or a broker intermediary who executes swaps on a SEF on the Portfolio’s behalf, against any losses or costs that may be incurred as a result of the Portfolio’s transactions on the SEF. In addition, a Portfolio may be subject to execution risk if it enters into a derivatives transaction that is required to be cleared, and no clearing member is willing to clear the transaction on the Portfolio’s behalf. In that case, the transaction might have to be terminated, and the Portfolio could lose some or all of the benefit of any increase in the value of the transaction after the time of the trade.

There are risks involved in dealing with the custodians or brokers who hold a Portfolio’s investments or settle a Portfolio’s trades. It is possible that, in the event of the insolvency or bankruptcy of a custodian or broker, a Portfolio would be delayed or prevented from recovering its assets from the custodian or broker, or its estate, and may have only a general unsecured claim against the custodian or broker for those assets. In recent insolvencies of brokers or other financial institutions, the ability of certain customers to recover their assets from the insolvent’s estate has been delayed, limited, or prevented, often unpredictably, and there is no assurance that any assets held by a Portfolio with a custodian or broker will be readily recoverable by the Portfolio. In addition, there may be limited recourse against non-U.S. sub-custodians in those situations in which a Portfolio invests in markets where custodial and/or settlement systems and regulations are not fully developed, including emerging markets, and the assets of the Portfolio have been entrusted to such sub-custodians. SSGA FM or an affiliate may serve as the custodian of the Portfolios.

Eurodollar Certificates of Deposit (“ECDs”), Eurodollar Time Deposits (“ETDs”) and Yankee Certificates of Deposit (“YCDs”)

Different risks than those associated with the obligations of domestic banks may exist for ECDs, ETDs and YCDs because the banks issuing these instruments, or their domestic or non-U.S. branches, are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations, and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of non-U.S. issuers also involve risks such as future unfavorable political and economic developments, withholding tax, seizures of non-U.S. deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

The Government National Mortgage Association (“GNMA” or “Ginnie Mae”) is the principal federal government guarantor of mortgage-related securities. GNMA is a wholly owned U.S. Government corporation within the Department of Housing and Urban Development. It guarantees, with the full faith and credit of the United States, full and timely payment of all monthly principal and interest on its mortgage-related securities. GNMA pass-through securities are considered to have a relatively low risk of default in that (1) the underlying mortgage loan portfolio is comprised entirely of government-backed loans and (2) the timely payment of both principal and interest on the securities is guaranteed by the full faith and credit of the U.S. Government, regardless of whether they

have been collected. GNMA pass-through securities are, however, subject to the same interest rate risk as comparable privately issued mortgage-related securities. Therefore, the effective maturity and market value of a Portfolio’s GNMA securities can be expected to fluctuate in response to changes in interest rate levels.

Residential mortgage loans are also pooled by the Federal Home Loan Mortgage Corporation (“FHLMC” or “Freddie Mac”), a corporate instrumentality of the U.S. Government. The mortgage loans in FHLMC’s portfolio are not government backed; FHLMC, not the U.S. Government, guarantees the timely payment of interest and ultimate collection of principal on FHLMC securities. FHLMC also issues guaranteed mortgage certificates, on which it guarantees semiannual interest payments and a specified minimum annual payment of principal.

The Federal National Mortgage Association (“FNMA” or “Fannie Mae”) is a government-sponsored corporation owned entirely by private stockholders. It is subject to general regulation by the Secretary of Housing and Urban Development. FNMA purchases residential mortgages from a list of approved seller/servicers, which include savings and loan associations, savings banks, commercial banks, credit unions and mortgage bankers. Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest only by FNMA, not the U.S. Government.

Each Portfolio may invest in illiquid securities. The absence of a regular trading market for illiquid securities imposes additional risks on investments in these securities. Illiquid securities may be difficult to value and may often be disposed of only after considerable expense and delay.

Each Money Market Portfolio (and Money Market Fund) is managed in accordance with Rule 2a-7 under the Investment Company Act of 1940, as amended (the “1940 Act”). As a result, each Money Market Portfolio (and Money Market Fund) has adopted the following liquidity policies (except as noted):

Under Rule 2a-7, “illiquid security” means a security that cannot be sold or disposed of in the ordinary course of business within seven calendar days at approximately the value ascribed to it by the seller.

Industrial development bonds are issued to finance a wide variety of capital projects including: electric, gas, water and sewer systems; ports and airport facilities; colleges and universities; and hospitals. The principal security for these bonds is generally the net revenues derived from a particular facility, group of facilities, or in some cases, the proceeds of a special excise tax or other specific revenue sources. Although the principal security behind these bonds may vary, many provide additional security in the form of a debt service reserve fund whose money may be used to make principal and interest payments on the issuer’s obligations. Some authorities provide further security in the form of a state’s ability without obligation to make up deficiencies in the debt service reserve fund.

Insured municipal securities are those for which scheduled payments of interest and principal are guaranteed by a private (non-governmental) insurance company. The insurance entitles a fund to receive only the face or par value of the securities held by the fund, but the ability to be paid is limited to the claims paying ability of the insurer. The insurance does not guarantee the market value of the municipal securities or the net asset value of a Portfolio’s shares. Insurers are selected based upon the diversification of their portfolios and the strength of the management team which contributes to the claims paying ability of the entity. However, the Adviser selects securities based upon the underlying credit, with bond insurance viewed as an enhancement only. The Adviser’s objective is to have an enhancement that provides additional liquidity to insulate against volatility in changing markets.

Securities markets may be susceptible to market manipulation (e.g., the potential manipulation of the London Interbank Offered Rate (“LIBOR”)) or other fraudulent trade practices, which could disrupt the orderly functioning of these markets or adversely affect the value of investments traded in these markets, including investments of a Fund.

The effect of any changes to, or discontinuation of, LIBOR on the Funds will vary depending, among other things, on (1) existing fallback or termination provisions in individual contracts and (2) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. Accordingly, it is difficult to predict the full impact of the transition away from LIBOR on the Funds until new reference rates and fallbacks for both legacy and new products, instruments and contracts are commercially accepted.

Recent political activity in the U.S. has increased the risk that the U.S. could default on some or any of its obligations. While it is impossible to predict the consequences of such an unprecedented event, it is likely that a default by the U.S. would be highly disruptive to the U.S. and global securities markets and could significantly impair the value of the Funds’ investments. Similarly, political events within the U.S. at times have resulted, and may in the future result, in a shutdown of government services, which could negatively affect the U.S. economy, decrease the value of many Fund investments, and increase uncertainty in or impair the operation of the U.S. or other securities markets. To the extent a Fund has focused its investments in the stock market index of a particular region, adverse geopolitical and other events could have a disproportionate impact on the Fund.

The Portfolios, except for the Treasury Portfolios, may invest in mortgage-related securities. Mortgage-related securities represent an interest in a pool of, or are secured by, mortgage loans. Mortgage-related securities may be issued or guaranteed by (i) U.S. Government agencies or instrumentalities such as GNMA, FNMA and FHLMC or (ii) other issuers, including private companies.

Many mortgage-related securities provide regular payments which consist of interest and, in most cases, principal. In contrast, other forms of debt securities normally provide for periodic payment of interest in fixed amounts with principal payments at maturity or specified call dates. In effect, payments on many mortgage-related securities are a “pass-through” of the payments made by the individual borrowers on their mortgage loans, net of any fees paid to the issuer or guarantor of such securities.

of the mortgage, and other social and demographic conditions. During periods of falling interest rates, the rate of mortgage prepayments tends to increase, thereby tending to decrease the life of mortgage-related securities. During periods of rising interest rates, the rate of mortgage prepayments usually decreases, thereby tending to increase the life of mortgage-related securities.

Because of the possibility of prepayments (and due to scheduled repayments of principal), mortgage-related securities are less effective than other types of securities as a means of “locking in” attractive long-term interest rates. Prepayments would have to be reinvested at lower rates. As a result, these securities may have less potential for capital appreciation during periods of declining interest rates than other securities of comparable maturities, although they may have a similar risk of decline in market value during periods of rising interest rates. Prepayments may also significantly shorten the effective maturities of these securities, especially during periods of declining interest rates. Conversely, during periods of rising interest rates, a reduction in prepayments may increase the effective maturities of these securities, subjecting them to a greater risk of decline in market value in response to rising interest rates than traditional debt securities, and, therefore, potentially increasing the volatility of the Portfolios.

Collateralized mortgage obligations (“CMOs”) may be issued by a U.S. Government agency or instrumentality or by a private issuer. CMOs are typically structured with classes or series that have different maturities and are generally retired in sequence. Each class of obligations receives periodic interest payments according to its terms. However, monthly principal payments and any prepayments from the collateral pool are generally paid first to the holders of the most senior class. Thereafter, payments of principal are generally allocated to the next most senior class of obligations until that class of obligations has been fully repaid. Any or all classes of obligations of a CMO may be paid off sooner than expected because of an increase in the payoff speed of the pool. Changes in prepayment rates may have significant effects on the values and the volatility of the various classes and series of a CMO. Payment of interest or principal on some classes or series of a CMO may be subject to contingencies or some classes or series may bear some or all of the risk of default on the underlying mortgages. Stripped mortgage-related securities are usually structured with two classes that receive different portions of the interest and principal distributions on a pool of mortgage loans. The yield to maturity on an interest only or “IO” class of stripped mortgage-related securities is extremely sensitive not only to changes in prevailing interest rates but also to the rate of principal payments (including prepayments) on the underlying assets. A rapid rate of principal prepayments may have a measurable adverse effect on a Fund’s yield to maturity to the extent it invests in IOs. If the assets underlying the IO experience greater than anticipated prepayments of principal, the Fund may fail to recoup fully, or at all, its initial investment in these securities. Conversely, principal only securities or “POs” tend to increase in value if prepayments are greater than anticipated and decline if prepayments are slower than anticipated. The secondary market for stripped mortgage-related securities may be more volatile and less liquid than that for other mortgage-related securities, potentially limiting a Portfolio’s ability to buy or sell those securities at any particular time.

The Portfolios may invest in municipal and municipal-related securities. Municipal securities may bear fixed, floating or variable rates of interest or may be zero coupon securities. Municipal securities are generally of two types: general obligations and revenue obligations. General obligations are backed by the full faith and credit of the issuer. These securities include tax anticipation notes, bond anticipation notes, general obligation bonds and commercial paper. Revenue obligations are backed by the revenues generated from a specific project or facility and include industrial development bonds and private activity bonds. Tax anticipation notes are issued to finance working capital needs of municipalities and are generally issued in anticipation of future tax revenues. Bond anticipation notes are issued in expectation of the issuer obtaining longer-term financing.

Municipal obligations are affected by economic, business or political developments. These securities may be subject to provisions of litigation, bankruptcy and other laws affecting the rights and remedies of creditors, or may become subject to future laws extending the time for payment of principal and/or interest, or limiting the rights of municipalities to levy taxes. The Portfolio may be more adversely impacted by changes in tax rates and policies than other funds. Because interest income from municipal securities is normally not subject to regular federal income taxation, the attractiveness of municipal securities in relation to other investment alternatives is affected by changes in federal income tax rates applicable to, or the continuing federal income tax-exempt status of, such interest income. Any proposed or actual changes in such rates or exempt status, therefore, can significantly affect the demand for and supply, liquidity and marketability of municipal securities. This could in turn affect a Portfolio’s ability to acquire and dispose of municipal securities at desirable yield and price levels. Concentration of a Portfolio’s investments in these municipal obligations will subject the Portfolio, to a greater extent than if such investment was not so concentrated, to the risks of adverse economic, business or political developments affecting the particular state, industry or other area of concentration. Issuers, including governmental issuers, of municipal securities may be unable to pay their obligations as they become due. Recent declines in tax revenues, and increases in liabilities, such as pension and health care liabilities, may increase the actual or perceived risk of default on such securities.

The Portfolios may purchase participation interests in municipal obligations, including municipal lease/purchase agreements. Municipal leases are an undivided interest in a portion of an obligation in the form of a lease or installment purchase issued by a state or local government to acquire equipment or facilities. These instruments may have fixed, floating or variable rates of interest, with remaining maturities of 13 months or less. Certain participation interests may permit a Portfolio to demand payment on not more than seven days’ notice, for all or any part of the Portfolio’s interest, plus accrued interest.

Municipal leases frequently have special risks not normally associated with general obligation or revenue bonds. Some leases or contracts include “non-appropriation” clauses, which provide that the governmental issuer has no obligation to make future payments under the lease or contract unless money is appropriated for such purpose by the appropriate legislative body on a yearly or other periodic basis. To reduce these risks, the Portfolios will only purchase municipal leases subject to a non-appropriation clause when the payment of principal and accrued interest is backed by a letter of credit or guarantee of a bank.

Whether a municipal lease agreement will be considered illiquid for the purpose of a Portfolio’s restriction on investments in illiquid securities will be determined in accordance with procedures established by the Board of Trustees.

In addition to the mortgage related securities discussed above, the Portfolios, except for the Treasury Portfolios and the U.S. Government Portfolio, may invest in asset-backed securities that are not mortgage-related. Asset-backed securities other than mortgage-related securities represent undivided fractional interests in pools of instruments, such as consumer loans, and are typically similar in structure to mortgage-related pass-through securities. Payments of principal and interest are passed through to holders of the securities and are typically supported by some form of credit enhancement, such as a letter of credit, surety bond, limited guarantee by another entity, or by priority to certain of the borrower’s other securities. The degree of credit-enhancement, if any, varies, applying only until exhausted and generally covering only a fraction of the security’s par value.

The value of such asset-backed securities is affected by changes in the market’s perception of the asset backing the security, changes in the creditworthiness of the servicing agent for the instrument pool, the originator of the instruments, or the financial institution providing any credit enhancement and the expenditure of any portion of any credit enhancement. The risks of investing in asset-backed securities are ultimately dependent upon payment of the underlying instruments by the obligors, and a Fund would generally have no recourse against the obligee of the instruments in the event of default by an obligor. The underlying instruments are subject to prepayments which shorten the duration of asset-backed securities and may lower their return, in generally the same manner as described above for prepayments of pools of mortgage loans underlying mortgage-related securities.

The interest and principal payments on pre-refunded municipal securities are typically paid from the cash flow generated from an escrow fund consisting of U.S. Government securities. These payments have been “pre-refunded” using the escrow fund.

Each Portfolio, except for the U.S. Government Portfolio and the Treasury Portfolios, may invest in securities that are purchased in private placements and, accordingly, are subject to restrictions on resale as a matter of contract or under federal securities laws. While such private placements may offer attractive opportunities for investment not otherwise available on the open market, the securities so purchased are often “restricted securities,” i.e., securities which cannot be sold to the public without registration under the Securities Act of 1933 (the “Securities Act”) or the availability of an exemption from registration (such as Rules 144 or 144A), or which are not readily marketable because they are subject to other legal or contractual delays in or restrictions on resale. Generally speaking, restricted securities may be sold only to qualified institutional buyers, or in a privately negotiated transaction to a limited number of purchasers, or in limited quantities after they have been held for a specified period of time and other conditions are met pursuant to an exemption from registration, or in a public offering for which a registration statement is in effect under the Securities Act. Because there may be relatively few potential purchasers for such investments, especially under adverse market or economic conditions or in the event of adverse changes in the financial condition of the issuer, the Portfolio could find it more difficult to sell such securities when the Adviser believes it advisable to do so or may be able to sell such securities only at prices lower than if such securities were more widely held. Market quotations for such securities are generally less readily available than for publicly traded securities. The absence of a trading market can make it difficult to ascertain a market value for such securities for purposes of computing the Portfolio’s net asset value, and the judgment of the Adviser may at times play a greater role in valuing these securities than in the case of publicly traded securities. Disposing of such securities, which may be illiquid investments, can involve time-consuming negotiation and legal expenses, and it may be difficult or impossible for the Portfolio to sell them promptly at an acceptable price. The Portfolio may have to bear the extra expense of registering such securities for resale and the risk of substantial delay in effecting such registration.

A Portfolio may be deemed to be an “underwriter” for purposes of the Securities Act when selling restricted securities to the public, and in such event the Fund may be liable to purchasers of such securities if the registration statement prepared by the issuer, or the prospectus forming a part of it, is materially inaccurate or misleading.

A tender option is a municipal obligation (generally held pursuant to a custodial arrangement) having a relatively long maturity and bearing interest at a fixed rate substantially higher than prevailing short-term tax exempt rates, that has been coupled with the agreement of a third party, such as a bank, broker-dealer or other financial institution, pursuant to which such institution grants the security holders the option, at periodic intervals, to tender their securities to the institution and receive the face value thereof. As consideration for providing the option, the financial institution receives periodic fees equal to the difference between the municipal obligation’s fixed coupon rate and the rate, as determined by a remarketing or similar agent at or near the commencement of such period, that would cause the securities, coupled with the tender option, to trade at par on the date of such determination. Thus, after

The Portfolios may invest in Inflation-Protection Securities (“TIPSs”), a type of inflation-indexed Treasury security. TIPSs typically provide for semiannual payments of interest and a payment of principal at maturity. In general, each payment will be adjusted to take into account any inflation or deflation that occurs between the issue date of the security and the payment date based on the Consumer Price Index for All Urban Consumers (“CPI-U”).

Each semiannual payment of interest will be determined by multiplying a single fixed rate of interest by the inflation-adjusted principal amount of the security for the date of the interest payment. Thus, although the interest rate will be fixed, the amount of each interest payment will vary with changes in the principal of the security as adjusted for inflation and deflation.

TIPSs also provide for an additional payment (a “minimum guarantee payment”) at maturity if the security’s inflation-adjusted principal amount for the maturity date is less than the security’s principal amount at issuance. The amount of the additional payment will equal the excess of the security’s principal amount at issuance over the security’s inflation-adjusted principal amount for the maturity date.

Each Portfolio may purchase U.S. Government securities. With respect to U.S. Government securities, the Treasury Portfolio will invest exclusively in direct obligations of the U.S. Treasury, such as U.S. Treasury bills, notes and bonds generally maturing within 397 days, and other mutual funds, subject to regulatory limitations, that invest exclusively in such obligations. The Treasury Plus Portfolio will invest only in direct obligations of the U.S. Treasury (U.S. Treasury bills, notes and bonds) and repurchase agreements collateralized by these obligations. The types of U.S. Government obligations in which each other Portfolio may at times invest include: (1) U.S. Treasury obligations and (2) obligations issued or guaranteed by U.S. Government agencies and instrumentalities which are supported by any of the following: (a) the full faith and credit of the U.S. Treasury, (b) the right of the issuer to borrow an amount limited to a specific line of credit from the U.S. Treasury, (c) discretionary authority of the U.S. Government agency or instrumentality, or (d) the credit of the instrumentality (examples of agencies and instrumentalities are: Federal Land Banks, Federal Housing Administration, Federal Farm Credit Bank, Farmers Home Administration, Export-Import Bank of the United States, Central Bank for Cooperatives, Federal Intermediate Credit Banks, Federal Home Loan Banks, General Services Administration, Maritime Administration, Tennessee Development Bank, Asian-American Development Bank, International Bank for Reconstruction and Development and Federal National Mortgage Association (“Fannie Mae” or “FNMA”). No assurance can be given that in the future the U.S. Government will provide financial support to U.S. Government securities it is not obligated to support.

The Portfolios may purchase U.S. Government obligations on a forward commitment basis.

The Portfolios, except for the Treasury Portfolios and the U.S. Government Portfolio, may invest in variable amount master demand notes which are unsecured obligations that are redeemable upon demand and are typically unrated. These instruments are issued pursuant to written agreements between their issuers and holders. The agreements permit the holders to increase (subject to an agreed maximum) and the holders and issuers to decrease the principal amount of the notes, and specify that the rate of interest payable on the principal fluctuates according to an agreed formula. Generally, changes in interest rates will have a smaller effect on the market value of these securities than on the market value of comparable fixed income obligations. Thus, investing in these securities generally allows less opportunity for capital appreciation and depreciation than investing in comparable fixed income securities. There may be no active secondary market with respect to a particular variable rate instrument.

provides for the automatic establishment of a new interest rate on set dates. Interest rates on these securities are ordinarily tied to widely recognized market rates, which are typically set once a day. Generally, changes in interest rates will have a smaller effect on the market value of variable and floating rate securities than on the market value of comparable fixed income obligations. Variable rate obligations will be deemed to have a maturity equal to the period remaining until the next readjustment of the interest rate.

Each Portfolio may purchase securities on a when-issued basis. Delivery of and payment for these securities may take place as long as a month or more after the date of the purchase commitment. The value of these securities is subject to market fluctuation during this period, and no income accrues to the Portfolio until settlement takes place. When entering into a when-issued transaction, the Portfolio will rely on the other party to consummate the transaction; if the other party fails to do so, the Portfolio may be disadvantaged. The Portfolios will not invest more than 25% of their respective net assets in when-issued securities.

Securities purchased on a when-issued basis and held by a Portfolio are subject to changes in market value based upon actual or perceived changes in the level of interest rates. Generally, the value of such securities will fluctuate inversely to changes in interest rates — i.e., they will appreciate in value when interest rates decline and decrease in value when interest rates rise. Therefore, if in order to achieve higher interest income a Portfolio remains substantially fully invested at the same time that it has purchased securities on a “when-issued” basis, there will be a greater possibility of fluctuation in the Portfolio’s NAV.

The Portfolios may invest in zero coupon securities. Zero coupon securities are notes, bonds and debentures that: (1) do not pay current interest and are issued at a substantial discount from par value; (2) have been stripped of their unmatured interest coupons and receipts; or (3) pay no interest until a stated date one or more years into the future. These securities also include certificates representing interests in such stripped coupons and receipts. Generally, changes in interest rates will have a greater impact on the market value of a zero coupon security than on the market value of the comparable securities that pay interest periodically during the life of the instrument. In the case of any zero-coupon debt obligations with a fixed maturity date of more than one year from the date of issuance that are treated as issued originally at a discount, a Portfolio will be required to accrue original issue discount (“OID”) for U.S. federal income tax purposes and, in the case of a Portfolio treated as a regulated investment company (“RIC”), may as a result be required to pay out as an income distribution an amount which is greater than the total amount of cash interest the Portfolio actually received. To generate sufficient cash to make the requisite distributions to maintain its qualification for treatment as a RIC under the Internal Revenue Code of 1986, as amended (the “Code”), a Portfolio that is taxed as a RIC may be required to sell investments, including at a time when it may not be advantageous to do so.

The Portfolios may invest no more than 25% of their respective total assets in stripped securities that have been stripped by their holder, typically a custodian bank or investment brokerage firm. Privately-issued stripped securities are not themselves guaranteed by the U.S. Government, but the future payment of principal or interest on U.S. Treasury obligations which they represent is so guaranteed.

A Portfolio may be required to earmark or otherwise segregate liquid assets in respect of its obligations under derivatives transactions that involve contractual obligations to pay in the future, or a Portfolio may engage in other measures to “cover” its obligations with respect to such transactions. The amounts that are earmarked or otherwise segregated may be based on the notional value of the derivative or on the daily mark-to-market obligation under the derivatives contract and may be reduced by amounts on deposit with the applicable broker or counterparty to the derivatives transaction. In certain circumstances, a Portfolio may enter into an offsetting position rather than earmarking or segregating liquid assets. A Portfolio may modify its asset segregation and coverage policies from time to time. Although earmarking or segregating may in certain cases have the effect of limiting a Portfolio’s ability to engage in derivatives transactions, the extent of any such limitation will depend on a variety of factors, including the method by which the Fund determines the nature and amount of assets to be earmarked or segregated.

The Portfolios in which the Funds invest each have substantially the same investment restrictions as their corresponding Funds. In reviewing the description of a Fund’s investment restrictions below, you should assume that the investment restrictions of the corresponding Portfolio are the same in all material respects as those of the Fund.

The Trust has adopted the following restrictions applicable to the Funds, which may not be changed without the affirmative vote of a “majority of the outstanding voting securities” of a Fund, which is defined in the 1940 Act to mean the affirmative vote of the lesser of (1) more than 50% of the outstanding shares of the Fund and (2) 67% or more of the shares present at a meeting if more than 50% of the outstanding shares are present at the meeting in person or by proxy.

With respect to investment policy on concentration (#6 above), a Money Market Fund may concentrate in bankers’ acceptances, certificates of deposit and similar instruments when, in the opinion of the Adviser, the yield, marketability and availability of investments meeting the Fund’s quality standards in the banking industry justify any additional risks associated with the concentration of the Fund’s assets in such industry.

For purposes of the above investment limitation number 6, in the case of a tax-exempt bond issued by a non-governmental user, where the tax-exempt bond is backed only by the assets and revenues of the non-governmental user, then such non-governmental user would be deemed to be the sole issuer. For each Fund, all percentage limitations (except the limitation to borrowings) on investments will apply at the time of the making of an investment and shall not be considered violated unless an excess or deficiency occurs or exists immediately after and as a result of such investment. Except for the investment restrictions expressly identified as fundamental, or to the extent designated as such in the Prospectus with respect to a Fund, the other investment policies described in this SAI or in the Prospectus are not fundamental and may be changed by approval of the Trustees without shareholder approval.

To the extent a Fund is subject to Rule 35d-1 under the 1940 Act, the Fund has an investment policy, described in the Fund’s prospectus, to, under normal circumstances, invest at least 80% of its assets in the particular types of investments suggested by the Fund’s name (a “Name Policy”). “Assets” for the purposes of a Name Policy are net assets plus the amount of any borrowings for investment purposes. The percentage limitation applies at the time of purchase of an investment. A Fund’s Name Policy may be changed by the Board of Trustees without shareholder approval. However, to the extent required by SEC regulations, shareholders will be provided with at least sixty (60) days’ notice prior to any change in a Fund’s Name Policy.

Fundamental Investment Restrictions (1) through (5), as numbered above limit a Fund’s ability to engage in certain investment practices and purchase securities or other instruments to the extent consistent with applicable law as that law changes from time to time. Applicable law includes the 1940 Act, the rules or regulations thereunder and applicable orders of SEC as are currently in place. In addition, interpretations and guidance provided by the SEC staff may be taken into account, where deemed appropriate by a Fund, to determine if an investment practice or the purchase of securities or other instruments is permitted by applicable law. As such, the effects of these limitations will change as the statute, rules, regulations or orders (or, if applicable, interpretations) change, and no shareholder vote will be required or sought when such changes permit or require a resulting change in practice.

The policies set forth below to be followed by State Street Bank and Trust Company (“State Street”) and SSGA FM ( collectively, the “Service Providers”) for the disclosure of information about the portfolio holdings of the SSGA Funds, State Street Master Funds, and State Street Institutional Investment Trust (each, a “Trust”). These disclosure policies are intended to ensure compliance by the Service Providers and the Trust with applicable regulations of the federal securities laws, including the 1940 Act and the Investment Advisers Act of 1940, as amended. The Board of Trustees must approve all material amendments to the policy.

It is the policy of the Service Providers to protect the confidentiality of client holdings and prevent the selective disclosure of non-public information concerning the Trust.

No information concerning the portfolio holdings of the Trust may be disclosed to any party (including shareholders) except as provided below. The Service Providers are not permitted to receive compensation or other consideration in connection with disclosing information about a Fund’s portfolio to third parties. In order to address potential conflicts between the interest of Fund shareholders, on the one hand, and those of the Service Providers or any affiliated person of those entities or of the Fund, on the other hand, the Fund’s policies require that non-public disclosures of information regarding the Fund’s portfolio may be made only if there is a legitimate business purpose consistent with fiduciary duties to all shareholders of the Fund.

The Board of Trustees exercises continuing oversight over the disclosure of each Fund’s holdings by (i) overseeing the implementation and enforcement of the portfolio holding disclosure policy, Codes of Ethics and other relevant policies of each Fund and its service providers by the Trust’s Chief Compliance Officer (“CCO”) and (2) considering reports and recommendations by the Trust’s CCO concerning any material compliance matters (as defined in Rule 38a-1 under the 1940 Act). The Board reserves the right to amend the policy at any time without prior notice in its sole discretion.

Publicly Available Information. Any party may disclose portfolio holdings information after the holdings are publicly available.

Information about each Fund’s 10 largest holdings generally is posted on the Funds’ website at SSGA.com within 30 days following the end of each month.

Portfolio managers and other senior officers or spokespersons of the Service Providers or the Trust may disclose or confirm the ownership of any individual portfolio holding position to reporters, brokers, shareholders, consultants or other interested persons only if such information has been previously publicly disclosed in accordance with these disclosure policies. For example, a portfolio manager discussing the Trust may indicate that he owns XYZ Company for the Trust only if the Trust’s ownership of such company has previously been publicly disclosed.

State Street Global Advisors’ (“SSGA”) trading desk may periodically distribute lists of investments held by its clients (including the Trust) for general analytical research purposes. In no case may such lists identify individual clients or individual client position sizes. Furthermore, in the case of equity securities, such lists shall not show aggregate client position sizes.

Confidentiality Agreement. No non-public disclosure of the Funds’ portfolio holdings will be made to any party unless such party has signed a written Confidentiality Agreement. For purposes of the disclosure policies, any Confidentiality Agreement must be in a form and substance acceptable to, and approved by, the Trust’s officers.

Evaluation Service Providers. There are numerous mutual fund evaluation services (such as Morningstar, Inc. and Broadridge Financial Solutions, Inc., formerly, Lipper, Inc.) and due diligence departments of broker-dealers and wirehouses that regularly analyze the portfolio holdings of mutual funds in order to monitor and report on various attributes. These services and departments then distribute the results of their analysis to the public, paid subscribers and/or in-house brokers. In order to facilitate the review of the Trust by these services and departments, the Trust may distribute (or authorize the Service Providers and the Trust’s custodian or fund accountants to distribute) month-end portfolio holdings to such services and departments only if such entity has executed a confidentiality agreement.

Additional Restrictions. Notwithstanding anything herein to the contrary, the Board of Trustees, State Street and SSGA FM may, on a case-by-case basis, impose additional restrictions on the dissemination of portfolio information beyond those found in these disclosure policies.

Waivers of Restrictions. These disclosure policies may not be waived, or exceptions made, without the consent of the Trust’s officers. All waivers and exceptions involving the Trust will be disclosed to the Board of Trustees no later than its next regularly scheduled quarterly meeting.

Disclosures Required by Law. Nothing contained herein is intended to prevent the disclosure of portfolio holdings information as may be required by applicable law. For example, SSGA FM, State Street, the Trust or any of its affiliates or service providers may file any report required by applicable law (such as Schedules 13D, 13G and 13F or Form N-MFP), respond to requests from regulators and comply with valid subpoenas.

The following lists the principal officers for the Trust and State Street Master Funds, as well as their mailing addresses and ages, positions with the Trusts and length of time served, and present and principal occupations:

The By-Laws of the Trust provide that the Trust shall indemnify each person who is or was a Trustee of the Trust against all expenses, judgments, fines, settlements and other amounts actually and reasonably incurred in connection with any proceedings if the person in good faith and reasonably believes that his or her conduct was in the Trust’s best interest. The Trust, at its expense, provides liability insurance for the benefit of its Trustees and officers.

Following is a summary of the experience, attributes and skills which qualify each Trustee to serve on the Boards of Trustees of the Trust and State Street Master Funds.

Mr. Costantino serves as a Trustee of the State Street Institutional Investment Trust, State Street Master Funds, Navigator Trust, SSGA Funds, Elfun Funds, State Street Institutional Funds (independent chairperson through 2016) and State Street Variable Insurance Funds, Inc. (independent chairperson through 2016).

The Board of Trustees has established various committees to facilitate the timely and efficient consideration of various matters of importance to Independent Trustees, the Trust, and the Trust’s shareholders and to facilitate compliance with legal and regulatory requirements. Currently, the Board has created an Audit Committee, Governance Committee, Valuation Committee, Nominating Committee and Qualified Legal Compliance Committee (the “QLCC”).

The Board has delegated management of the Trust to service providers who are responsible for the day-to-day management of risks applicable to the Trust. The Board oversees risk management for the Trust in several ways. The Board receives regular reports from both the CCO and administrator for the Trust, detailing the results of the Trust’s compliance with its Board-adopted policies and procedures, the investment policies and limitations of the Funds, and applicable provisions of the federal securities laws and the Code. As needed, the Adviser discusses management issues regarding the Trust with the Board, soliciting the Board’s input on many aspects of management, including potential risks to the Funds. The Board’s Audit Committee also receives reports on various aspects of risk that might affect the Trust and offers advice to management, as appropriate. The Trustees also meet in executive session with the independent counsel to the Independent Trustees, the independent registered public accounting firm, counsel to the Trust, the CCO and representatives of management, as needed. Through these regular reports and interactions, the Board oversees the risk management parameters for the Trust, which are effected on a day-to-day basis by service providers to the Trust.

The Trust has adopted proxy voting procedures pursuant to which the Trust delegates the responsibility for voting proxies relating to portfolio securities held by the Portfolios to the Adviser as part of the Adviser’s general management of the Portfolios, subject to the Board’s continuing oversight. A copy of the Trust’s proxy voting procedures is located in Appendix B and a copy of the Adviser’s proxy voting procedures is located in Appendix C.

Shareholders may receive information regarding how the Funds voted proxies relating to portfolio securities during the most recent 12-month period ending June 30 (i) by calling (877) 521-4083 or (ii) on the SEC’s website at www.sec.gov.

Persons or organizations owning 25% or more of the outstanding shares of a Fund may be presumed to “control” (as that term is defined in the 1940 Act) a Fund. As a result, these persons or organizations could have the ability to approve or reject those matters submitted to the shareholders of such Fund for their approval.

The Adviser is responsible for the investment management of the Funds pursuant to the Amended and Restated Investment Advisory Agreement dated November 17, 2015 as amended from time to time (the “Advisory Agreement”), by and between the Adviser and the Trust. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation, a publicly held financial holding company. State Street is a wholly-owned subsidiary of State Street Corporation.

The Advisory Agreement will continue from year to year provided that such continuance is specifically approved at least annually by (a) the Trustees or by the vote of a majority of the outstanding voting securities of a Fund, and (b) vote of a majority of the Independent Trustees, cast in person at a meeting called for the purpose of voting on such approval. The Advisory Agreement may be terminated by the Adviser or the Trust without penalty upon sixty days’ notice and will terminate automatically upon its assignment. The Adviser and its affiliates may have deposit, loan and other commercial banking relationships with the issuers of obligations that may be purchased on behalf of the Funds, including outstanding loans to such issuers that could be repaid in whole or in part with the proceeds of securities so purchased. Such affiliates deal, trade and invest for their own accounts in such obligations and are among the leading dealers of various types of such obligations. The Adviser has informed the Funds that, in making its investment decisions, it will not obtain or use material non-public information in its possession or in the possession of any of its affiliates. In making investment recommendations for a Fund, the Adviser will not inquire or take into consideration whether an issuer of securities proposed for purchase or sale by the Fund is a customer of the Adviser, its parent or its subsidiaries or affiliates and, in dealing with its customers, the Adviser, its parent, subsidiaries and affiliates will not inquire or take into consideration whether securities of such customers were held by any fund managed by the Adviser or any such affiliate.

Investment decisions for the Trust and for the Adviser’s other clients are made with a view to achieving their respective investment objectives. It may develop that a particular security is bought or sold for only one client even though it might be held by, or bought or sold for, other clients. Likewise, a particular security may be bought for one or more clients when one or more clients are selling that same security. Some simultaneous transactions are inevitable when several clients receive investment advice from the same investment adviser, particularly when the same security is suitable for the investment objectives of more than one client. When two or more clients are simultaneously engaged in the purchase or sale of the same security, the securities are allocated among clients in a manner believed to be equitable to each. The Trust recognizes that in some cases this system could have a detrimental effect on the price or volume of the security as far as a Fund is concerned. However, it is believed that the ability of each Fund to participate in volume transactions will produce better executions for the Funds.

The Adviser is also the investment adviser to each of the related Portfolios pursuant to an investment advisory agreement (the “Portfolio Advisory Agreement”) between the Adviser and State Street Master Funds, on behalf of the Portfolios. The Adviser receives an investment advisory fee with respect to each related Portfolio. The Portfolio Advisory Agreement is the same in all material respects as the Advisory Agreement between the Trust on behalf of the Funds and the Adviser. Each Fund that invests in a related Portfolio bears a proportionate part of the management fees paid by the Portfolio (based on the percentage of the Portfolio’s assets attributable to the Fund).

For the services provided under the Advisory Agreement and the Portfolio Advisory Agreement, each Fund pays the Adviser a fee at an annual rate set forth below of the Fund’s average daily net assets.

From time to time, the Adviser may contractually agree to waive the advisory fee and/or reimburse certain Fund expenses in excess of a certain percentage of average daily net assets on an annual basis (an “expense limitation”). The amount of advisory fees waived and/or reimbursed during the past fiscal year is shown below.

The administration fees paid to SSGA FM for the last three fiscal years are set forth in the table below.

State Street serves as the sub-administrator for the Trust, pursuant to a sub-administration agreement dated June 1, 2015 (the “Sub-Administration Agreement”). State Street serves as the custodian for the Trust, pursuant to a custody agreement dated April 11, 2012 (the “Custody Agreement”). Under the Sub-Administration Agreement, State Street is obligated to provide certain sub-administrative services to the Trust. Under the Custody Agreement, State Street is obligated to provide certain custody services to the Trust, as well as basic portfolio recordkeeping required by the Trust for regulatory and financial reporting purposes. State Street is a wholly owned subsidiary of State Street Corporation, a publicly held financial holding company, and is affiliated with the Adviser. State Street’s mailing address is State Street Financial Center, One Lincoln Street, Boston, Massachusetts 02111-2900.

As consideration for sub-administration services, State Street receives an annual fee from the Adviser (payable monthly). As consideration for custody and fund accounting services, each Fund pays State Street an annual fee (payable monthly) based on the average monthly net assets of each Fund. Each Fund also pays State Street transaction and service fees for these services and reimburses State Street for out-of-pocket expenses.

The sub-administration, custodian and fund accounting fees paid by the Funds to State Street for the last three fiscal years are set forth in the table below.

DST Asset Manager Solutions, Inc. serves as the Transfer and Dividend Paying Agent. DST Asset Manager Solutions, Inc. is paid for the following annual account services and activities including but not limited to: establishment and maintenance of each shareholder’s account; closing an account; acceptance and processing of trade orders; preparation and transmission of payments for dividends and distributions declared by each Fund; customer service support including receipt of correspondence and responding to shareholder and financial intermediary inquiries; investigation services; tax related support; financial intermediary fee payment processing; and charges related to compliance and regulatory services.

Portfolio fees are allocated to each Fund based on the average net asset value of each Fund and are billable on a monthly basis at the rate of 1/12 of the annual fee. DST Asset Manager Solutions, Inc. is reimbursed by each Fund for supplying certain out-of-pocket expenses including confirmation statements, investor statements, banking fees, postage, forms, audio response, telephone, records retention, customized programming/enhancements, reports, transcripts, microfilm, microfiche, and expenses incurred at the specific direction of the Fund. DST Asset Manager Solutions, Inc. principal business address is 2000 Crown Colony Drive, Quincy, MA 02169.

The Trust, the Adviser and SSGA FD have each adopted a code of ethics (together, the “Codes of Ethics”) pursuant to Rule 17j-1 under the 1940 Act as required by applicable law, which is designed to prevent affiliated persons of the Trust, the Adviser and SSGA FD from engaging in deceptive, manipulative or fraudulent activities in connection with securities held or to be acquired by the Funds (which may also be held by persons subject to the Codes of Ethics). The Codes of Ethics permit personnel, subject to the Codes of Ethics and their provisions, to invest in securities for their personal investment accounts, subject to certain limitations, including securities that may be purchased or held by the Trust, Adviser, State Street or SSGA FD.

SSGA FD serves as the distributor of the Funds pursuant to the Distribution Agreement by and between SSGA FD and the Trust. Pursuant to the Distribution Agreement, the Funds, except for the Treasury Obligations Fund, pay SSGA FD fees under the Rule 12b-1 Plan in effect for the Funds. For a description of the fees paid to SSGA FD under the Rule 12b-1 Plan, see “Distribution Plans,” below. SSGA FD is an indirect wholly-owned subsidiary of State Street Corporation. SSGA FD’s mailing address is One Iron Street, Boston, MA 02210.

To compensate SSGA FD for the services it provides and for the expenses it bears in connection with the distribution of shares of the Funds, SSGA FD will be entitled to receive any front-end sales load applicable to the sale of shares of the Fund. Each Fund, except for the Treasury Obligations Fund, may make payments (“Rule 12b-1 Fees”) from the assets attributable to certain classes of its shares to SSGA FD under a distribution plan adopted pursuant to Rule 12b-1 under the 1940 Act (the “Distribution Plan”). The Distribution Plan is a compensation plan that provides for payments at annual rates (based on average daily net assets) set out below. Because Rule 12b-1 Fees are paid on an ongoing basis, they will increase the cost of your investment and may cost you more than paying other types of sales loads. The principal business address of SSGA FD is One Iron Street, Boston, MA 02210.

The Distribution Plan may benefit the Funds by increasing sales of shares and reducing redemptions of shares, resulting potentially, for example, in economies of scale and more predictable flows of cash into and out of the Funds. Because Rule 12b-1 fees are paid out of a Fund’s assets, all shareholders share in that expense; however, because shareholders hold their shares through varying arrangements (for example, directly or through financial intermediaries), they may not share equally in the benefits of the Distribution Plan.

maintaining shareholder account registrations; sub-accounting with respect to shares held in omnibus accounts; receiving and processing purchase and redemption orders, including aggregated orders, and delivering orders to the Fund’s transfer agent; processing and delivering trade confirmations, periodic statements, prospectuses, annual reports, semi-annual reports, shareholder notices, and other SEC-required communications; processing dividend and distribution payments and issuing related documentation; providing shareholder tax reporting and processing tax data; receiving, tabulating, and transmitting proxies for proxy solicitations; and responding to inquiries from shareholders. Shareholder servicing fees paid for the last fiscal year included amounts paid to affiliates of the Adviser and SSGA FD including State Street Bank (on behalf of all of its North America business units) and State Street Global Markets, LLC and Global Services divisions of State Street Bank and Trust Company. These affiliates of the Adviser are also among the financial intermediaries that may receive fees from the Distribution Plan.

The Shareholder Servicing Agreement calls for payments by the ILR Fund, Treasury Fund, Treasury Plus Fund and U.S. Government Fund at an annual rate (based on average net assets) as follows:

Financial intermediaries are firms that sell shares of mutual funds, including the Funds, and/or provide certain administrative and account maintenance services to mutual fund shareholders. Financial intermediaries may include, among others, brokers, financial planners or advisors, banks, retirement plan recordkeepers, and insurance companies. In some cases, a financial intermediary may hold its clients’ Fund shares in nominee or street name and may utilize omnibus accounts. Shareholder services provided by a financial intermediary may (though they will not necessarily) include, among other things: establishing and maintaining shareholder account registrations; sub-accounting with respect to shares held in omnibus accounts; receiving and processing purchase and redemption orders, including aggregated orders, and delivering orders to the Fund’s transfer agent; processing and delivering trade confirmations, periodic statements, prospectuses, annual reports, semi-annual reports, shareholder notices, and other SEC-required communications; processing dividend and distribution payments and issuing related documentation; providing shareholder tax reporting and processing tax data; receiving, tabulating, and transmitting proxies for proxy solicitations; and responding to inquiries from shareholders.

Some portion of SSGA FD’s payments to financial intermediaries will be made out of amounts received by SSGA FD under the Distribution Plans and pursuant to the Shareholder Servicing Agreement. In addition, the Funds may reimburse SSGA FD for payments SSGA FD makes to financial intermediaries that provide recordkeeping, shareholder servicing, sub-transfer agency, administrative and/or account maintenance services (collectively, “servicing”). The amount of the reimbursement for servicing compensation and the manner in which it is calculated are reviewed by the Trustees periodically.

If you invest through a Financial Intermediary and meet the eligibility criteria for more than one share class, you should discuss with your Financial Intermediary which share class is appropriate for you. Your financial adviser and the Financial Intermediary employing him or her may have an incentive to recommend one share class over another, when you are eligible to invest in more than one share class. Please speak with your financial adviser to learn more about the total amounts paid to your financial adviser and his or her firm by the Fund or its affiliates with respect to the different share classes offered by the Fund.

SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide compensation to financial intermediaries in connection with sales of the Funds’ shares or servicing of shareholders or shareholder accounts by financial intermediaries. Such compensation may include, but is not limited to, ongoing payments, financial assistance to financial intermediaries in connection with conferences, sales, or training programs for their employees, seminars for the public, advertising or sales campaigns, or other financial intermediary-sponsored special events. In some instances, this compensation may be made available only to certain financial intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Financial intermediaries may not use sales of the Funds’ shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA. The level of payments made to a financial intermediary in any given year will vary and, in the case of most financial intermediaries, will not exceed 0.05% of the value of assets attributable to the financial intermediary invested in shares of funds in the SSGA FM-fund complex. In certain cases, the payments described in the preceding sentence are subject to minimum payment levels.

If payments to financial intermediaries by the distributor or adviser for a particular mutual fund complex exceed payments by other mutual fund complexes, your financial advisor and the financial intermediary employing him or her may have an incentive to recommend that fund complex over others. Please speak with your financial advisor to learn more about the total amounts paid to your financial advisor and his or her firm by SSGA FD and its affiliates, and by sponsors of other mutual funds he or she may recommend to you. You should also consult disclosures made by your financial intermediary at the time of purchase. Because the Funds pay distribution, service and other fees for the sale of their shares and for services provided to shareholders out of the Funds’ assets on an ongoing basis, over time those fees will increase the cost of an investment in a Fund.

A Fund may pay distribution fees, service fees and other amounts described above at a time when shares of the Fund are not being actively promoted to new investors generally, or when shares of that Fund are unavailable for purchase.

Ropes & Gray LLP serves as counsel to the Trust. The principal business address of Ropes & Gray LLP is 800 Boylston Street, Boston, Massachusetts 02199. Sullivan & Worcester LLP, located at One Post Office Square, Boston, Massachusetts 02109, serves as independent counsel to the Independent Trustees.

In placing a portfolio transaction, the Adviser seeks to achieve best execution. The Adviser’s duty to seek best execution requires the Adviser to take reasonable steps to obtain for the client as favorable an overall result as possible for Fund portfolio transactions under the circumstances, taking into account various factors that are relevant to the particular transaction.

The Adviser refers to and selects from the list of approved trading counterparties maintained by the Adviser’s Credit Risk Management team. In selecting a trading counterparty for a particular trade, the Adviser seeks to weigh relevant factors including, but not limited to the following:

In selecting a trading counterparty, the price of the transaction and costs related to the execution of the transaction typically merit a high relative importance, depending on the circumstances. The Adviser does not necessarily select a trading counterparty based upon price and costs but may take other relevant factors into account if it believes that these are important in taking reasonable steps to obtain the best possible result for a Fund under the circumstances. Consequently, the Adviser may cause a client to pay a trading counterparty more than another trading counterparty might have charged for the same transaction in recognition of the value and quality of the brokerage services provided. The following matters may influence the relative importance that the Adviser places upon the relevant factors:

(i) The nature and characteristics of the order or transaction. For example, size of order, market impact of order, limits, or other instructions relating to the order;

(ii) The characteristics of the financial instrument(s) or other assets which are the subject of that order. For example, whether the order pertains to an equity, fixed income, derivative or convertible instrument;

(iii) The characteristics of the execution venues to which that order can be directed, if relevant. For example, availability and capabilities of electronic trading systems;

The process by which trading counterparties are selected to effect transactions is designed to exclude consideration of the sales efforts conducted by broker-dealers in relation to the Funds.

Under the Declaration of Trust, the Trustees are authorized to issue an unlimited number of shares of each Fund. Upon liquidation or dissolution of a Fund, investors are entitled to share pro rata in the Fund’s net assets available for distribution to its investors. Investments in a Fund have no preference, preemptive, conversion or similar rights, except as determined by the Trustees or as set forth in the Bylaws, and are fully paid and non-assessable, except as set forth below.

The Declarations of Trust of the Trust and the Master Trust each provide that a Trust may redeem shares of a Fund at the redemption price that would apply if the share redemption were initiated by a shareholder. It is the policy of each Trust that, except upon such conditions as may from time to time be set forth in the then current prospectus of a Fund or to facilitate a Trust’s or a Fund’s compliance with applicable law or regulation, a Trust would not initiate a redemption of shares unless it were to determine that failing to do so may have a substantial adverse consequence for a Fund or the Trust.

Each Trust’s Declaration of Trust provides that a Trustee who is not an “interested person” (as defined in the 1940 Act) of a Trust will be deemed independent and disinterested with respect to any demand made in connection with a derivative action or proceeding. It is the policy of each Trust that it will not assert that provision to preclude a shareholder from claiming that a Trustee is not independent or disinterested with respect to any demand made in connection with a derivative action or proceeding; provided, however, that the foregoing policy will not prevent the Trusts from asserting applicable law (including Section 2B of Chapter 182 of the Massachusetts General Laws) to preclude a shareholder from claiming that a Trustee is not independent or disinterested with respect to any demand made in connection with a derivative action or proceeding.

A Trust will not deviate from the foregoing policies in a manner that adversely affects the rights of shareholders of a Fund without the approval of “a vote of a majority of the outstanding voting securities” (as defined in the 1940 Act) of such Fund.

Each shareholder is entitled to a vote in proportion to the number of Fund shares it owns. Shares do not have cumulative voting rights in the election of Trustees, and shareholders holding more than 50% of the aggregate outstanding shares in the Trust may elect all of the Trustees if they choose to do so. The Trust is not required and has no current intention to hold annual meetings of shareholders but the Trust will hold special meetings of shareholders when in the judgment of the Trustees it is necessary or desirable to submit matters for a shareholder vote.

Treasury Fund, Treasury Plus Fund, Treasury Obligations Fund and U.S. Government Fund

Each Fund seeks to maintain a constant price per share of $1.00 for purposes of sales and redemptions of shares by using the amortized cost valuation method to value its portfolio instruments in accordance with Rule 2a-7 under the 1940 Act. There can be no assurance that the $1.00 NAV per share will be maintained. The amortized cost method involves valuing an instrument at its cost and thereafter assuming a constant amortization to maturity of any discount or premium, even though the portfolio security may increase or decrease in market value, generally in response to changes in interest rates. While this method provides certainty in valuation, it may result in periods during which value, as determined by amortized cost, is higher or lower than the price each Fund would receive if it sold the instrument.

For example, in periods of declining interest rates, the daily yield on each of the Fund’s shares computed by dividing the annualized daily income on the Fund’s portfolio by the NAV based upon the amortized cost valuation technique may tend to be higher than a similar computation made by using a method of valuation based upon market prices and estimates thereof. In periods of rising interest rates, the daily yield on each Fund’s shares computed the same way may tend to be lower than a similar computation made by using a method of calculation based upon market prices and estimates.

The Trustees have established procedures reasonably designed to stabilize each Fund’s price per share at $1.00. These procedures include: (1) the determination of the deviation from $1.00, if any, of each Fund’s NAV using market values; (2) periodic review by the Trustees of the amount of and the methods used to calculate the deviation; and (3) maintenance of records of such determination. The Trustees will promptly consider what action, if any, should be taken if such deviation exceeds 1/2 of one percent.

The following discussion of U.S. federal income tax consequences of an investment in the Funds is based on the Code, U.S. Treasury regulations, and other applicable authority, as of the date of this SAI. These authorities are subject to change by legislative or administrative action, possibly with retroactive effect. The following discussion is only a summary of some of the important U.S. federal income tax considerations generally applicable to investments in the Funds. There may be other tax considerations applicable to particular shareholders. Shareholders should consult their own tax advisors regarding their particular situation and the possible application of foreign, state and local tax laws.

Each Fund invests substantially all of its assets in a corresponding Portfolio (which may be a series of State Street Master Funds) (in each case, a “Portfolio”), and so substantially all of each such Fund’s income will result from distributions or deemed distributions, or allocations, as the case may be, from the corresponding Portfolio. Therefore, as applicable, references to the U.S. federal income tax treatment of the Funds, including to the assets owned and the income earned by the Funds, will be to or will include such treatment of the corresponding Portfolio, and, as applicable, the assets owned and the income earned by the corresponding Portfolio. See “Tax Considerations Applicable to Funds Investing in Portfolios Treated as Partnerships” and “Tax Considerations Applicable to Funds Investing in Portfolios Treated as RICs” below for further information.

Special tax rules apply to investments through defined contribution plans and other tax-qualified plans or tax-advantaged arrangements. Shareholders should consult their tax advisers to determine the suitability of shares of a Fund as an investment through such plans and arrangements and the precise effect of an investment on their particular tax situations.

Each Fund has elected or intends to elect to be treated as a RIC under Subchapter M of the Code and intends each year to qualify and be eligible to be treated as such. In order to qualify for the special tax treatment accorded RICs and their shareholders, each Fund must, among other things, (a) derive at least 90% of its gross income for each taxable year from (i) dividends, interest, payments with respect to certain securities loans, gains from the sale of securities or foreign currencies, or other income (including but not limited to gains from options, futures or forward contracts) derived with respect to its business of investing in such stock, securities or currencies and (ii) net income derived from interests in “qualified publicly traded partnerships” (as defined below); (b) diversify its holdings so that, at the end of each quarter of the Fund’s taxable year, (i) at least 50% of the value of the Fund’s total assets consists of cash and cash items, U.S. Government securities, securities of other RICs, and other securities limited in respect of any one issuer to a value not greater than 5% of the value of the Fund’s total assets and no more than 10% of the outstanding voting securities of such issuer, and (ii) no more than 25% of its assets are invested, including through corporations in which the Fund owns a 20% or more voting stock interest, (x) in the securities (other than those of the U.S. Government or other RICs) of any one issuer or of two or more issuers which the Fund controls and which are engaged in the same, similar or related trades and businesses, or (y) in the securities of one or more qualified publicly traded partnerships (as defined below); and (c) distribute with respect to each taxable year at least 90% of the sum of its investment company taxable income (as that term is defined in the Code without regard to the deduction for dividends paid – generally taxable ordinary income and the excess, if any, of net short-term capital gains over net long-term capital losses) and net tax-exempt income, for such year.

In general, for purposes of the 90% gross income requirement described in (a) above, income derived from a partnership will be treated as qualifying income only to the extent such income is attributable to items of income of the partnership which would be qualifying income if realized directly by the RIC.

identification of the issuer (or issuers) is uncertain under current law, and an adverse determination or future guidance by the Internal Revenue Service (“IRS”) with respect to issuer identification for a particular type of investment may adversely affect a Fund’s ability to meet the diversification test in (b) above.

If a Fund qualifies as a RIC that is accorded special tax treatment, the Fund will not be subject to federal income tax on income or gains distributed in a timely manner to its shareholders in the form of dividends (including Capital Gain Dividends, as defined below). If a Fund were to fail to meet the income, diversification or distribution test described above, the Fund could in some cases cure such failure, including by paying a Fund-level tax, paying interest or disposing of certain assets. If such Fund were ineligible to or otherwise did not cure such failure for any year, or if such Fund were otherwise to fail to qualify as a RIC accorded special tax treatment in any taxable year, the Fund would be subject to tax at the Fund level on its taxable income at corporate rates, and all distributions from earnings and profits, including any distributions of net tax-exempt income (if any) and net capital gains (as defined below), would be taxable to shareholders as ordinary income. Some portions of such distributions may be eligible for the dividends-received deduction in the case of corporate shareholders and may be eligible to be treated as “qualified dividend income” in the case of shareholders taxed as individuals, provided, in both cases, the shareholder meets certain holding period and other requirements in respect of a Fund’s shares (each as described below). In addition, a Fund could be required to recognize unrealized gains, pay substantial taxes and interest and make substantial distributions before re-qualifying as a RIC that is accorded special tax treatment.

In determining its net capital gain, including in connection with determining the amount available to support a Capital Gain Dividend (as defined below), its taxable income, and its earnings and profits, a RIC generally may elect to treat part or all of any post-October capital loss (defined as any net capital loss attributable to the portion, if any, of the taxable year after October 31 or, if there is no such loss, the net long-term capital loss or net short-term capital loss attributable to any such portion of the taxable year) or late-year ordinary loss (generally, the sum of its (i) net ordinary loss, if any, from the sale, exchange or other taxable disposition of property, attributable to the portion, if any, of the taxable year after October 31, and its (ii) other net ordinary loss, if any, attributable to the portion, if any, of the taxable year after December 31) as if incurred in the succeeding taxable year.

If a Fund were to fail to distribute in a calendar year at least an amount equal, in general, to the sum of 98% of its ordinary income for such year and 98.2% of its capital gain net income for the one-year period ending October 31 of such year (or November 30 or December 31, if the Fund is eligible to elect and so elects), plus any such amounts retained from the prior year, the Fund would be subject to a nondeductible 4% excise tax on the undistributed amounts. For purposes of the required excise tax distribution, a RIC’s ordinary gains and losses from the sale, exchange or other taxable disposition of property that would otherwise be taken into account after October 31 of a calendar year (or November 30, if the Fund makes the election referred to above) generally are treated as arising on January 1 of the following calendar year; in the case of a Fund with a December 31 year end that makes the election described above, no such gains or losses will be so treated. Also, for these purposes, a Fund will be treated as having distributed any amount on which it is subject to corporate income tax for the taxable year ending within the calendar year. Each Fund intends generally to make distributions sufficient to avoid imposition of the excise tax, although there can be no assurance that it will be able to do so. Distributions declared by a Fund during October, November and December to shareholders of record on a date in any such month and paid by the Fund during the following January will be treated for federal tax purposes as paid by the Fund and received by shareholders on December 31 of the year in which declared.

to one or more subsequent taxable years without expiration; any such carryforward losses will retain their character as short-term or long-term. The Fund must apply such carryforwards first against gains of the same character. See a Fund’s most recent annual shareholder report for the Fund’s available capital loss carryovers as of the end of its most recently ended fiscal year.

For U.S. federal income tax purposes, distributions of investment income are generally taxable to shareholders as ordinary income. Taxes on distributions of capital gains are determined by how long a Fund owned (or is deemed to have owned) the investments that generated them, rather than how long a shareholder has owned his or her Fund shares. In general, a Fund will recognize long-term capital gain or loss on the disposition of assets the Fund has owned (or is deemed to have owned) for more than one year, and short-term capital gain or loss on the disposition of investments the Fund has owned (or is deemed to have owned) for one year or less. Distributions of net-capital gain (that is, the excess of net long-term capital gain over net short-term capital loss) that are properly reported by a Fund as capital gain dividends (“Capital Gain Dividends”) generally will be taxable to a shareholder receiving such distributions as long-term capital gains includible in net capital gain and taxed to individuals at reduced rates relative to ordinary income. Distributions from capital gains are generally made after applying any available capital loss carryovers. The IRS and the Department of the Treasury have issued regulations that impose special rules in respect of Capital Gain Dividends received through partnership interests constituting “applicable partnership interests” under Section 1061 of the Code. The Funds do not expect to distribute Capital Gain Dividends. Distributions of net short-term capital gain (as reduced by any net long-term capital loss for the taxable year) will be taxable to shareholders as ordinary income. Distributions of investment income properly reported by a Fund and, in the case of a Fund investing in a Portfolio treated as a RIC, the Portfolio, as derived from “qualified dividend income” will be taxed in the hands of individuals at the rates applicable to net capital gain, provided holding period and other requirements are met at each of the shareholder, the Portfolio and, in the case of a Fund investing in a Portfolio treated as a RIC, the Fund level. The Funds do not expect Fund distributions to be derived from qualified dividend income.

The Code generally imposes a 3.8% Medicare contribution tax on the net investment income of certain individuals, trusts and estates to the extent their income exceeds certain threshold amounts. For these purposes, “net investment income” generally includes, among other things, (i) distributions paid by a Fund of net investment income and capital gains, and (ii) any net gain from the sale, redemption, exchange or other taxable disposition of Fund shares. Shareholders are advised to consult their tax advisors regarding the possible implications of this additional tax on their investment in a Fund.

If a Fund makes a distribution to a shareholder in excess of the Fund’s current and accumulated earnings and profits in any taxable year, the excess distribution will be treated as a return of capital to the extent of such shareholder’s tax basis in its shares, and thereafter as capital gain. A return of capital is not taxable, but it reduces a shareholder’s tax basis in its shares, thus reducing any loss or increasing any gain on a subsequent taxable disposition by the shareholder of its shares.

Shareholders of a Fund will be subject to federal income taxes as described herein on distributions made by the Fund whether received in cash or reinvested in additional shares of the Fund.

Distributions with respect to a Fund’s shares are generally subject to U.S. federal income tax as described herein to the extent they do not exceed the Fund’s realized income and gains, even though such distributions may economically represent a return of a particular shareholder’s investment. Such distributions are likely to occur in respect of shares purchased at a time when a Fund’s NAV includes either unrealized gains, or realized but undistributed income or gains, that were therefore included in the price the shareholder paid. Such distributions may reduce the fair market value of the Fund’s shares below the shareholder’s cost basis in those shares. As described above, a Fund is required to distribute realized income and gains regardless of whether the Fund’s NAV also reflects unrealized losses.

In order for some portion of the dividends received by a Fund shareholder to be “qualified dividend income,” the corresponding Portfolio must meet holding period and other requirements with respect to the dividend-paying stocks held by the Portfolio, the shareholder must meet holding period and other requirements with respect to the Fund’s shares, and in the case of a Fund investing in a Portfolio treated as a RIC, the Fund must meet holding period and other requirements with respect to its shares in the Portfolio. In general, a dividend will not be treated as qualified dividend income (at any of the Portfolio, Fund or shareholder level, as applicable) (a) if the dividend is received with respect to any share of stock held for fewer than 61 days during the 121-day period beginning on the date which is 60 days before the date on which such share becomes ex-dividend with respect to such dividend (or, in the case of certain preferred stock, 91 days during the 181-day period beginning 90 days before such date), (b) to the extent that the recipient is under an obligation (whether pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property, (c) if the recipient elects to have the dividend income treated as investment income for purposes of the limitation on deductibility of investment interest, or (d) if the dividend is received from a foreign corporation that is (i) not eligible for the benefits of a comprehensive income tax treaty with the United States (with the exception of dividends paid on stock of such a foreign corporation readily tradable on an established securities market in the United States) or (ii) treated as a passive foreign investment company.

In general, distributions of investment income properly reported by a Fund as derived from qualified dividend income will be treated as qualified dividend income in the hands of a shareholder taxed as an individual, provided the shareholder meets the holding period and other requirements described above with respect to the Fund’s shares. If the aggregate qualified dividends (a) allocated to a Fund by a Portfolio that is treated as a partnership or (b) received by a Fund from a Portfolio that is treated as a RIC, during any taxable year are 95% or more of the Fund’s gross income (excluding net long-term capital gain over net short-term capital loss), then 100% of the Fund’s dividends (other than dividends properly reported as Capital Gain Dividends) will be eligible to be treated as qualified dividend income.

In general, dividends of net investment income received by corporate shareholders of a Fund will qualify for the dividends-received deduction generally available to corporations to the extent of the amount of eligible dividends from domestic corporations received by a Portfolio (a) that is treated as a partnership and allocated to the Fund, or (b) that is treated as a RIC and in turn paid by the Portfolio to the Fund for the taxable year. A dividend so allocated or paid to a Fund will not be treated as a dividend eligible for the dividends-received deduction (at any of the Portfolio, Fund or shareholder level, as applicable) (a) if it has been received with respect to any share of stock that the Portfolio has held for less than 46 days (91 days in the case of certain preferred stock) during the 91-day period beginning on the date which is 45 days before the date on which such share becomes ex-dividend with respect to such dividend (during the 181-day period beginning 90 days before such date in the case of certain preferred stock) or (b) to the extent that the Portfolio is under an obligation (pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property. Moreover, a Fund that invests in a corresponding Portfolio that is treated as a RIC must meet similar requirements with respect to its shares of the corresponding Portfolio. Finally, the dividends-received deduction may otherwise be disallowed or reduced (x) if the corporate shareholder fails to satisfy the foregoing requirements with respect to its shares of the Fund or (y) by application of various provisions of the Code (for instance, the dividends-received deduction is reduced in the case of a dividend received on debt-financed portfolio stock (generally, stock acquired with borrowed funds)). The Funds do not expect Fund distributions to be eligible for the dividends-received deduction.

Any distribution of income that is attributable to (a) income received by a Fund in lieu of dividends with respect to securities on loan pursuant to a securities lending transaction or (b) dividend income received by a Fund on securities it temporarily purchased from a counterparty pursuant to a repurchase agreement that is treated for U.S. federal income tax purposes as a loan by the Fund, will not constitute qualified dividend income to individual shareholders and will not be eligible for the dividends-received deduction for corporate shareholders.

If a Fund holds, directly or indirectly, one or more “tax credit bonds” issued on or before December 31, 2017, on one or more applicable dates during a taxable year, the Fund may elect to permit its shareholders to claim a tax credit on their income tax returns equal to each shareholder’s proportionate share of tax credits from the bond otherwise allowed to the Fund. In such a case, a shareholder will be deemed to receive a distribution of money with respect to its Fund shares equal to the shareholder’s proportionate share of the amount of such credits and be allowed a credit against the shareholder’s U.S. federal income tax equal to the amount of such deemed distribution. A shareholder’s ability to claim a tax credit associated with one or more tax credit bonds may be subject to certain limitations imposed by the Code, and the amount of the tax credits may not exceed the amount reported by the Fund in a written notice to shareholders. Even if a Fund is eligible to pass through tax credits to shareholders, the Fund may choose not to do so.

Tax Considerations Applicable to Funds Investing in Portfolios Treated as Partnerships

Certain Funds invest substantially all of their investable assets in a corresponding Portfolio that is treated as a partnership for U.S. federal income tax purposes. In such cases the nature and character of each such Fund’s income, gains, losses and deductions will generally be determined at the Portfolio level and each such Fund will be allocated its share of Portfolio income and gains. As applicable, references to income, gains, losses and deductions of a Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of a Fund will be to the Fund’s allocable share of the assets of the corresponding Portfolio.

Such a Fund may be required to redeem a portion of its interest in a Portfolio in order to obtain sufficient cash to make the requisite distributions to maintain its qualification for treatment as a RIC. The Portfolio in turn may be required to sell investments in order to meet such redemption requests, including at a time when it may not be advantageous to do so.

In addition, in certain circumstances, the “wash sale” rules under Section 1091 of the Code may apply to the Funds’ sales of the corresponding Portfolio interests that have generated losses. A wash sale occurs if equity interests of an issuer are sold by a Fund at a loss and the Fund acquires additional interests of that same issuer 30 days before or after the date of the sale. The wash sale rules could defer losses in a Fund’s hands on corresponding interests in a Portfolio (to the extent such sales are wash sales) for extended (and, in certain cases, potentially indefinite) periods of time.

The following considerations are relevant to shareholders of Funds that invest substantially all of their assets in a corresponding Portfolio that has elected or intends to elect to be treated and to qualify and be eligible to be treated each year as a RIC.

Substantially all of such a Fund’s income will result from distributions or deemed distributions from the corresponding Portfolio. Additionally, whether a Fund will meet the asset diversification test described above will depend on whether the corresponding Portfolio meets each of the income, diversification and distribution tests. If a Portfolio were to fail to meet any such test and were ineligible to or otherwise were not to cure such failure, the corresponding Fund would as a result itself fail to meet the asset diversification test and might be ineligible or unable to or might otherwise not cure such failure.

Because each Fund invests substantially all of its assets in shares of the corresponding Portfolio, its distributable income and gains will normally consist substantially of distributions from the corresponding Portfolio. To the extent that a Portfolio realizes net losses on its investments for a given taxable year, the corresponding Fund will not be able to benefit from those losses until, and only to the extent that (i) the Portfolio realizes gains that it can reduce by those losses, or (ii) the Fund recognizes its share of those losses when it disposes of shares of the Portfolio in a transaction qualifying for sale or exchange treatment. Moreover, even when a Fund does make such a disposition, any loss will be recognized as a capital loss, a portion of which may be a long-term capital loss. The Funds will not be able to offset any capital losses from its dispositions of shares of the corresponding Portfolio against its ordinary income (including distributions of any net short-term capital gains realized by a Portfolio), and the Fund’s long-term capital losses first offset its long-term capital gains, increasing the likelihood that the Fund’s short-term capital gains are distributed to shareholders as ordinary income.

In addition, in certain circumstances, the “wash sale” rules under Section 1091 of the Code may apply to the Funds’ sales of the corresponding Portfolio shares that have generated losses. A wash sale occurs if shares of an issuer are sold by a Fund at a loss and the Fund acquires additional shares of that same issuer 30 days before or after the date of the sale. The wash-sale rules could defer losses in a Fund’s hands on corresponding Portfolio shares (to the extent such sales are wash sales) for extended (and, in certain cases, potentially indefinite) periods of time.

Finally, a RIC generally must look through its 20 percent voting interest in a corporation, including a RIC, to the underlying assets thereof for purposes of the diversification test; special rules potentially provide limited relief from the application of this rule where a RIC owns such an interest in an underlying RIC (as defined below), such as a Portfolio.

If a Fund receives dividends from a Portfolio treated as a RIC, or a Portfolio receives dividends from a mutual fund, an ETF or another investment company that qualifies as a RIC (each an “underlying RIC”) and the underlying RIC reports such dividends as qualified dividend income, then the Fund, or Portfolio, as applicable, is permitted, in turn, to report a portion of its distributions as “qualified dividend income,” provided the Fund, or Portfolio, as applicable, meets the holding period and other requirements with respect to shares of the underlying RIC.

If a Fund or Portfolio receives dividends from an underlying RIC and the underlying RIC reports such dividends as eligible for the dividends-received deduction, then the Fund or Portfolio, as applicable, is permitted, in turn, to report a portion of its distributions as eligible for the dividends-received deduction as well when it distributes such portion to its shareholders, provided holding period and other requirements are met.

If an underlying RIC in which a Fund invests elects to pass through tax credit bond credits to its shareholders, then the Fund is permitted in turn to elect to pass through its proportionate share of those tax credits to its shareholders, provided that the Fund meets shareholder notice and other requirements.

The Code’s wash sale rule may also apply to certain redemptions and exchanges by non-U.S. shareholders. See “Non-U.S. Shareholders” below.

Special Rules for Debt Obligations. Some debt obligations with a fixed maturity date of more than one year from the date of issuance (and zero-coupon debt obligations with a fixed maturity date of more than one year from the date of issuance) will be treated as debt obligations that are issued originally at a discount. Generally, OID is treated as interest income and is included in a Fund’s income and required to be distributed by the Fund over the term of the debt obligation, even though payment of that amount is not received until a later time, upon partial or full repayment or disposition of the debt obligation. In addition, payment-in-kind obligations will give rise to income which is required to be distributed and is taxable even though the Fund holding the obligation receives no interest payment in cash on the obligation during the year.

Some debt obligations with a fixed maturity date of more than one year from the date of issuance that are acquired in the secondary market by a Fund may be treated as having “market discount.” Very generally, market discount is the excess of the stated redemption price of a debt obligation (or in the case of an obligation issued with OID, its “revised issue price”) over the purchase price of such obligation. Subject to the discussion below regarding Section 451 of the Code, (i) generally, any gain recognized on the disposition of, and any partial payment of principal on, a debt obligation having market discount is treated as ordinary income to the extent the gain, or principal payment, does not exceed the “accrued market discount” on such debt obligation, (ii) alternatively, a Fund may elect to accrue market discount currently, in which case the Fund will be required to include the accrued market discount in income (as ordinary income) and thus distribute it over the term of the debt obligation, even though payment of that amount is not received until a later time, upon partial or full repayment or disposition of the debt obligation and (iii) the rate at which the market discount accrues, and thus is included in a Fund’s income, will depend upon which of the permitted accrual methods the Fund elects. Notwithstanding the foregoing, effective for taxable years beginning after 2017, Section 451 of the Code generally requires any accrual method taxpayer to take into account items of gross income no later than the time at which such items are taken into account as revenue in the taxpayer’s financial statements. The IRS and the Department of Treasury have issued final regulations providing that this rule does not apply to the accrual of market discount. If this rule were to apply to the accrual of market discount, each Fund would be required to include in income any market discount as it takes the same into account on its financial statements even if the Fund does not otherwise elect to accrue market discount currently for federal income tax purposes.

If a Fund holds the foregoing kinds of obligations, or other obligations subject to special rules under the Code, the Fund may be required to pay out as an income distribution each year an amount which is greater than the total amount of cash interest the Fund actually received. Such distributions may be made from the cash assets of the Fund or, if necessary, by disposition of portfolio securities including at a time when it may not be advantageous to do so. These dispositions may cause a Fund to realize higher amounts of short-term capital gains (generally taxed to shareholders at ordinary income tax rates) and, in the event the Fund realizes net capital gains from such transactions, its shareholders may receive a larger Capital Gain Dividend than they would have if the Fund had not held such obligations.

A portion of the OID accrued on certain high yield discount obligations may not be deductible to the issuer and will instead be treated as a dividend paid by the issuer for purposes of the dividends-received deduction. In such cases, if the issuer of the high yield discount obligations is a domestic corporation, dividend payments by a Fund may be eligible for the dividends-received deduction to the extent attributable to the deemed dividend portion of such OID.

Securities Purchased at a Premium. Very generally, where a Fund purchases a bond at a price that exceeds the redemption price at maturity – that is, at a premium – the premium is amortizable over the remaining term of the bond. In the case of a taxable bond, if a Fund makes an election applicable to all such bonds it purchases, which election is irrevocable without consent of the IRS, the Fund reduces the current taxable income from the bond by the amortized premium and reduces its tax basis in the bond by the amount of such offset; upon the disposition or maturity of such bonds acquired on or after January 4, 2013, the Fund is permitted to deduct any remaining premium allocable to a prior period.

At-risk or Defaulted Securities. Investments in debt obligations that are at risk of or in default present special tax issues for the Funds. Tax rules are not entirely clear about issues such as when a Fund may cease to accrue interest, OID or market discount; whether, when or to what extent the Fund should recognize market discount on such a debt obligation; when and to what extent a Fund may take deductions for bad debts or worthless securities; and how a Fund should allocate payments received on obligations in default between principal and income. These and other related issues will be addressed by a Fund when, as and if it invests in such securities, in order to seek to ensure that it distributes sufficient income to preserve its status as a RIC and does not become subject to U.S. federal income or excise tax.

In general, excess inclusion income allocated to shareholders (i) cannot be offset by net operating losses (subject to a limited exception for certain thrift institutions), (ii) will constitute unrelated business taxable income (“UBTI”) to entities (including a qualified pension plan, an individual retirement account, a 401(k) plan, a Keogh plan or other tax-exempt entity) subject to tax on UBTI, thereby potentially requiring such an entity that is allocated excess inclusion income, and that otherwise might not be required to file a tax return, to file a tax return and pay tax on such income, and (iii) in the case of a foreign shareholder will not qualify for any reduction in U.S. federal withholding tax. A shareholder will be subject to U.S. federal income tax on such inclusions notwithstanding any exemption from such income tax otherwise available under the Code.

Foreign Currency Transactions. Any transaction by a Fund in foreign currencies, foreign currency-denominated debt obligations or certain foreign currency options, futures contracts or forward contracts (or similar instruments) may give rise to ordinary income or loss to the extent such income or loss results from fluctuations in the value of the foreign currency concerned. Any such net gains could require a larger dividend toward the end of the calendar year. Any such net losses will generally reduce and potentially require the recharacterization of prior ordinary income distributions. Such ordinary income treatment may accelerate a Fund’s distributions to shareholders and increase the distributions taxed to shareholders as ordinary income. Any net ordinary losses so created cannot be carried forward by the Fund to offset income or gains earned in subsequent taxable years.

Options and Futures. In general, option premiums received by a Fund are not immediately included in the income of the Fund. Instead, the premiums are recognized when the option contract expires, the option is exercised by the holder, or the Fund transfers or otherwise terminates the option (e.g., through a closing transaction). If a call option written by a Fund is exercised and the Fund sells or delivers the underlying stock, the Fund generally will recognize capital gain or loss equal to (a) the sum of the strike price and the option premium received by the Fund minus (b) the Fund’s basis in the stock. Such gain or loss generally will be short-term or long-term depending upon the holding period of the underlying stock. If securities are purchased by a Fund pursuant to the exercise of a put option written by it, the Fund generally will subtract the premium received for purposes of computing its cost basis in the securities purchased. Gain or loss arising in respect of a termination of a Fund’s obligation under an option other than through the exercise of the option will be short-term gain or loss depending on whether the premium income received by the Fund is greater or less than the amount paid by the Fund (if any) in terminating the transaction. Thus, for example, if an option written by a Fund expires unexercised, the Fund generally will recognize short-term gain equal to the premium received.

A Fund’s options activities may include transactions constituting straddles for U.S. federal income tax purposes, that is, that trigger the U.S. federal income tax straddle rules contained primarily in Section 1092 of the Code. Such straddles include, for example, positions in a particular security, or an index of securities, and one or more options that offset the former position, including options that are “covered” by a Fund’s long position in the subject security. Very generally, where applicable, Section 1092 requires (i) that losses be deferred on positions deemed to be offsetting positions with respect to “substantially similar or related property,” to the extent of unrealized gain in the latter, and (ii) that the holding period of such a straddle position that has not already been held for the long-term holding period be terminated and begin anew once the position is no longer part of a straddle. Options on single stocks that are not “deep in the money” may constitute qualified covered calls, which generally are not subject to the straddle rules; the holding period on stock underlying qualified covered calls that are “in the money” although not “deep in the money” will be suspended during the period that such calls are outstanding. Thus, the straddle rules and the rules governing qualified covered calls could cause gains that would otherwise constitute long-term capital gains to be treated as short-term capital gains, and distributions that would otherwise constitute “qualified dividend income” or qualify for the dividends-received deduction to fail to satisfy the holding period requirements and therefore to be taxed as ordinary income or fail to qualify for the dividends-received deduction, as the case may be.

The tax treatment of certain positions entered into by a Fund, including regulated futures contracts, certain foreign currency positions and certain listed non-equity options, will be governed by section 1256 of the Code (“section 1256 contracts”). Gains or losses on section 1256 contracts generally are considered 60% long-term and 40% short-term capital gains or losses (“60/40”), although certain foreign currency gains and losses from such contracts may be treated as ordinary in character. Also, section 1256 contracts held by a Fund at the end of each taxable year (and, for purposes of the 4% excise tax, on certain other dates as prescribed under the Code) are “marked to market” with the result that unrealized gains or losses are treated as though they were realized and the resulting gain or loss is treated as ordinary or 60/40 gain or loss, as applicable.

Derivatives, Hedging, and Related Transactions. In addition to the special rules described above in respect of futures and options transactions, a Fund’s transactions in other derivative instruments (e.g., forward contracts and swap agreements), as well as any of its hedging, short sale, securities loan or similar transactions, may be subject to one or more special tax rules (e.g., notional principal contract, straddle, constructive sale, wash sale and short sale rules). These rules may affect whether gains and losses recognized by a Fund are treated as ordinary or capital, accelerate the recognition of income or gains to the Fund, defer losses to the Fund, and cause adjustments in the holding periods of the Fund’s securities, thereby affecting whether capital gains and losses are treated as short-term or long-term. These rules could therefore affect the amount, timing and/or character of distributions to shareholders.

Because these and other tax rules applicable to these types of transactions are in some cases uncertain under current law, an adverse determination or future guidance by the IRS with respect to these rules (which determination or guidance could be retroactive) may affect whether a Fund has made sufficient distributions, and otherwise satisfied the relevant requirements, to maintain its qualification as a RIC and avoid a Fund-level tax.

Book-Tax Differences. Certain of a Fund’s investments in derivative instruments and foreign currency-denominated instruments, and any of the Fund’s transactions in foreign currencies and hedging activities, are likely to produce a difference between its book income and the sum of its taxable income and net tax-exempt income (if any). If such a difference arises, and a Fund’s book income is less than the sum of its taxable income and net tax-exempt income, the Fund could be required to make distributions exceeding book income to qualify as a RIC that is accorded special tax treatment and to avoid an entity-level tax. In the alternative, if a Fund’s book income exceeds the sum of its taxable income (including realized capital gains) and net tax-exempt income, the distribution (if any) of such excess generally will be treated as (i) a dividend to the extent of the Fund’s remaining earnings and profits (including earnings and profits arising from tax-exempt income), (ii) thereafter, as a return of capital to the extent of the recipient’s basis in its shares, and (iii) thereafter as gain from the sale or exchange of a capital asset.

A Fund’s income, proceeds and gains from sources within foreign countries may be subject to non-U.S. withholding or other taxes, which will reduce the yield of those investments. Tax conventions between certain countries and the United States may reduce or eliminate such taxes. Shareholders generally will not be entitled separately to claim a credit or deduction in respect of non-U.S. taxes paid or treated as paid by the Fund.

A Fund generally is required to withhold and remit to the U.S. Treasury a percentage of the taxable distributions and redemption proceeds paid to any individual shareholder who fails to properly furnish the Fund with a correct taxpayer identification number (“TIN”), who has under-reported dividend or interest income, or who fails to certify to the Fund that he or she is not subject to such withholding.

Backup withholding is not an additional tax. Any amounts withheld may be credited against the shareholder’s U.S. federal income tax liability, provided the appropriate information is furnished to the IRS.

Income of a RIC that would be UBTI if earned directly by a tax-exempt entity will not generally constitute UBTI when distributed to a tax-exempt shareholder of the RIC. Notwithstanding this “blocking” effect, a tax-exempt shareholder could realize UBTI by virtue of its investment in a Fund if shares in the Fund constitute debt-financed property in the hands of the tax-exempt shareholder within the meaning of Code Section 514(b).

any time during any taxable year a CRT (or one of certain other tax-exempt shareholders, such as the United States, a state or political subdivision, or an agency or instrumentality thereof, and certain energy cooperatives) is a record holder of a share in a RIC that recognizes “excess inclusion income,” then the RIC will be subject to a tax on that portion of its “excess inclusion income” for the taxable year that is allocable to such shareholders at the highest federal corporate income tax rate. The extent to which this IRS guidance remains applicable in light of the December 2006 legislation is unclear. To the extent permitted under the 1940 Act, each Fund may elect to specially allocate any such tax to the applicable CRT, or other shareholder, and thus reduce such shareholder’s distributions for the year by the amount of the tax that relates to such shareholder’s interest in a Fund. CRTs are urged to consult their tax advisors concerning the consequences of investing in each Fund.

Redemptions and exchanges of each Fund’s shares are taxable events and, accordingly, shareholders may realize gain or loss on these transactions. In general, any gain or loss realized upon a taxable disposition of shares will be treated as long-term capital gain or loss if the shares have been held for more than 12 months. Otherwise, the gain or loss on the taxable disposition of Fund shares will be treated as short-term capital gain or loss. However, any loss realized upon a taxable disposition of Fund shares held by a shareholder for six months or less will be treated as long-term, rather than short-term, to the extent of any Capital Gain Dividends received (or deemed received) by the shareholder with respect to the shares. Further, subject to the discussion below regarding money market funds, all or a portion of any loss realized upon a taxable disposition of Fund shares generally will be disallowed under the Code’s “wash sale” rule if other substantially identical shares are purchased, including by means of dividend reinvestment, within 30 days before or after the disposition. In such a case, the basis of the newly purchased shares will be adjusted to reflect the disallowed loss.

Upon the redemption or exchange of shares of a Fund, the Fund or, in the case of shares purchased through a financial intermediary, the financial intermediary may be required to provide you and the IRS with cost basis and certain other related tax information about the Fund shares you redeemed or exchanged. See the Funds’ prospectuses for more information.

Non-U.S. shareholders in a Fund should consult their tax advisors concerning the tax consequences of ownership of shares in the Fund. Distributions by a Fund to shareholders that are not “U.S. persons” within the meaning of the Code ( “foreign shareholders”) properly reported by the Fund as (1) Capital Gain Dividends, (2) short-term capital gain dividends, and (3) interest-related dividends, each as defined and subject to certain conditions described below, generally are not subject to withholding of U.S. federal income tax.

In general, the Code defines (1) “short-term capital gain dividends” as distributions of net short-term capital gains in excess of net long-term capital losses and (2) “interest-related dividends” as distributions from U.S.-source interest income of types similar to those not subject to U.S. federal income tax if earned directly by an individual foreign shareholder, in each case to the extent such distributions are properly reported as such by a Fund in a written notice to shareholders.

The exceptions to withholding for Capital Gain Dividends and short-term capital gain dividends do not apply to (A) distributions to an individual foreign shareholder who is present in the United States for a period or periods aggregating 183 days or more during the year of the distribution and (B) distributions attributable to gain that is treated as effectively connected with the conduct by the foreign shareholder of a trade or business within the United States under special rules regarding the disposition of U.S. real property interests as described below. The exception to withholding for interest-related dividends does not apply to distributions to a foreign shareholder (i) that has not provided a satisfactory statement that the beneficial owner is not a U.S. person, (ii) to the extent that the dividend is attributable to certain interest on an obligation if the foreign shareholder is the issuer or is a 10% shareholder of the issuer, (iii) that is within certain foreign countries that have inadequate information exchange with the United States, or (iv) to the extent the dividend is attributable to interest paid by a person that is a related person of the foreign shareholder and the foreign shareholder is a controlled foreign corporation. If a Fund invests in a RIC that pays such distributions to the Fund, such distributions retain their character as not subject to withholding if properly reported when paid by the Fund to foreign shareholders. A RIC is permitted to report such parts of its dividends as are eligible to be treated as interest-related or short-term capital gain dividends, but is not required to do so. In the case of shares held through an intermediary, the intermediary may withhold even if a Fund reports all or a portion of a payment as an interest-related or short-term capital gain dividend to shareholders.

Foreign shareholders should contact their intermediaries regarding the application of withholding rules to their accounts.

Distributions by a Fund to foreign shareholders other than Capital Gain Dividends, short-term capital gain dividends and interest-related dividends (e.g., dividends attributable to dividend and foreign-source interest income or to short-term capital gains or U.S. source interest income to which the exception from withholding described above does not apply) are generally subject to withholding of U.S. federal income tax at a rate of 30% (or lower applicable treaty rate).

A foreign shareholder is not, in general, subject to U.S. federal income tax on gains (and is not allowed a deduction for losses) realized on the sale of shares of a Fund unless (a) such gain is effectively connected with the conduct of a trade or business carried on by such holder within the United States, (b) in the case of an individual holder, the holder is present in the United States for a period or periods aggregating 183 days or more during the year of the sale and certain other conditions are met, or (c) the special rules relating to gain attributable to the sale or exchange of “U.S. real property interests” (“USRPIs”) apply to the foreign shareholder’s sale of shares of the Fund (as described below).

Foreign shareholders with respect to whom income from a Fund is effectively connected with a trade or business conducted by the foreign person within the United States will in general be subject to U.S. federal income tax on the income derived from the Fund at the graduated rates applicable to U.S. citizens, residents or domestic corporations, whether such income is received in cash or reinvested in shares of the Fund and, in the case of a foreign corporation, may also be subject to a branch profits tax. If a foreign shareholder is eligible for the benefits of a tax treaty, any effectively connected income or gain will generally be subject to U.S. federal income tax on a net basis only if it is also attributable to a permanent establishment maintained by the shareholder in the United States. More generally, foreign shareholders who are residents in a country with an income tax treaty with the United States may obtain different tax results than those described herein, and are urged to consult their tax advisors.

Special rules would apply if a Fund were a qualified investment entity (“QIE”) because it is either a “U.S. real property holding corporation” (“USRPHC”) or would be a USRPHC but for the operation of certain exceptions to the definition thereof. Very generally, a USRPHC is a domestic corporation that holds USRPIs the fair market value of which equals or exceeds 50% of the sum of the fair market values of the corporation’s USRPIs, interests in real property located outside the United States, and other trade or business assets. USRPIs are generally defined as any interest in U.S. real property and any interest (other than solely as a creditor) in a USRPHC or, very generally, an entity that has been a USRPHC in the last five years. A Fund that holds, directly or indirectly, significant interests in real estate investment trusts (“REITs”) may be a USRPHC. Interests in domestically controlled QIEs, including REITs and RICs that are QIEs, not-greater-than-10% interests in publicly traded classes of stock in REITs and not-greater-than-5% interests in publicly traded classes of stock in RICs generally are not USRPIs, but these exceptions do not apply for purposes of determining whether a Fund is a QIE. If an interest in a Fund were a USRPI, the Fund would be required to withhold U.S. tax on the proceeds of a share redemption by a greater-than-5% foreign shareholder, in which case such foreign shareholder generally would also be required to file U.S. tax returns and pay any additional taxes due in connection with the redemption.

If a Fund were a QIE under a special “look-through” rule, any distributions by the Fund to a foreign shareholder attributable directly or indirectly to (i) distributions received by the Fund from a lower-tier REIT that the Fund is required to treat as USRPI gain in its hands and (ii) gains realized on the disposition of USRPIs by the Fund, would retain their character as gains realized from USRPIs in the hands of the Fund’s foreign shareholders and would be subject to U.S. tax withholding. In addition, such distributions could result in the foreign shareholder being required to file a U.S. tax return and pay tax on the distributions at regular U.S. federal income tax rates. The consequences to a foreign shareholder, including the rate of such withholding and character of such distributions (e.g., as ordinary income or USRPI gain), would vary depending upon the extent of the foreign shareholder’s current and past ownership of the Fund. Each Fund generally does not expect that it will be a QIE.

Foreign shareholders of a Fund also may be subject to “wash sale” rules to prevent the avoidance of the tax-filing and –payment obligations discussed above through the sale and repurchase of Fund shares.

Foreign shareholders should consult their tax advisers and, if holding shares through intermediaries, their intermediaries, concerning the application of these rules to their investment in a Fund.

Special rules (including withholding and reporting requirements) apply to foreign partnerships and those holding Fund shares through foreign partnerships. Additional considerations may apply to foreign trusts and estates. Investors holding Fund shares through foreign entities should consult their tax advisers about their particular situation.

A foreign shareholder may be subject to state and local tax and to the U.S. federal estate tax in addition to the U.S. federal income tax on income referred to above.

Shareholder Reporting Obligations With Respect To Foreign Bank and Financial Accounts

Shareholders that are U.S. persons and own, directly or indirectly, more than 50% of a Fund by vote or value could be required to report annually their “financial interest” in the Fund’s “foreign financial accounts,” if any, on FinCEN Form 114, Report of Foreign Bank and Financial Accounts (“FBAR”). Shareholders should consult a tax advisor, and persons investing in a Fund through an intermediary should contact their intermediary, regarding the applicability to them of this reporting requirement.

Sections 1471-1474 of the Code and the U.S. Treasury and IRS guidance issued thereunder (collectively, “FATCA”) generally require a Fund to obtain information sufficient to identify the status of each of its shareholders under FATCA or under an applicable intergovernmental agreement (an “IGA”) between the United States and a foreign government. If a shareholder fails to provide the requested information or otherwise fails to comply with FATCA or an IGA, the Fund may be required to withhold under FATCA at a rate of 30% with respect to that shareholder on ordinary dividends it pays. The IRS and the Department of Treasury have issued proposed regulations providing that these withholding rules will not apply to the gross proceeds of share redemptions or Capital Gain Dividends a Fund pays. If a payment by a Fund is subject to FATCA withholding, the Fund is required to withhold even if such payment would otherwise be exempt from withholding under the rules applicable to foreign shareholders described above (e.g., short- term capital gain dividends and interest-related dividends).

Each prospective investor is urged to consult its tax adviser regarding the applicability of FATCA and any other reporting requirements with respect to the prospective investor’s own situation, including investments through an intermediary.

SSGA FD serves as the Funds’ distributor pursuant to the Distribution Agreement by and between SSGA FD and the Trust. Pursuant to the Distribution Agreement, the Funds pay SSGA FD fees under the Rule 12b-1 Plan in effect for the Funds. For a description of the fees paid to SSGA FD under the Rule 12b-1 Plan, see “Distribution Plans,” above. SSGA FD is not obligated to sell any specific number of shares and will sell shares of a Fund on a continuous basis only against orders to purchase shares. The principal business address of SSGA FD is One Iron Street, Boston, MA 02210.

Ratings assigned on Moody’s global long-term rating scale are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default on contractually promised payments and the expected financial loss suffered in the event of default.

Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.

Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.

A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.

Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.

Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.

B: Obligations rated B are considered speculative and are subject to high credit risk.

Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.

Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.

C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.

Note: Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*

Ratings assigned on Moody’s global short-term rating scale are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default on contractually promised payments and the expected financial loss suffered in the event of default.

P-1: Issuers (or supporting institutions) rated Prime-1 have a superior ability to repay short-term debt obligations.

P-2: Issuers (or supporting institutions) rated Prime-2 have a strong ability to repay short-term debt obligations.

P-3: Issuers (or supporting institutions) rated Prime-3 have an acceptable ability to repay short-term obligations.

NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.

An S&P Global Ratings issue credit rating is a forward-looking opinion about the creditworthiness of an obligor with respect to a specific financial obligation, a specific class of financial obligations, or a specific financial program (including ratings on medium-term note programs and commercial paper programs). It takes into consideration the creditworthiness of guarantors, insurers, or other forms of credit enhancement on the obligation and takes into account the currency in which the obligation is denominated. The opinion reflects S&P Global Ratings’ view of the obligor’s capacity and willingness to meet its financial commitments as they come due, and this opinion may assess terms, such as collateral security and subordination, which could affect ultimate payment in the event of default.

Issue credit ratings can be either long-term or short-term. Short-term ratings are generally assigned to those obligations considered short-term in the relevant market. Short-term ratings are also used to indicate the creditworthiness of an obligor with respect to put features on long-term obligations. Medium-term notes are assigned long-term ratings.

AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P Global Ratings. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.

AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.

A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.

BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.

BB; B; CCC; CC; and C: Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.

BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.

B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.

CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.

CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P Global Ratings expects default to be a virtual certainty, regardless of the anticipated time to default.

C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.

D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P Global Ratings believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. An obligation’s rating is lowered to ‘D’ if it is subject to a distressed exchange offer.

NR: This indicates that no rating has been requested, or that there is insufficient information on which to base a rating, or that S&P Global Ratings does not rate a particular obligation as a matter of policy.

A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P Global Ratings. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.

A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.

A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.

B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.

C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.

D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P Global Ratings believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. An obligation’s rating is lowered to ‘D’ if it is subject to a distressed exchange offer.

Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (IDRs). IDRs are also assigned to certain entities in global infrastructure and project finance. IDRs opine on an entity’s relative vulnerability to default on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.

In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.

‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.

‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.

‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.

‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.

‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.

‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met; however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:

‘D’ ratings indicate an issuer that in Fitch’s opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business.

Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.

In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.

A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations and up to 36 months for obligations in U.S. public finance markets.

F1: Highest Short-Term Credit Quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

F2: Good Short-Term Credit Quality. Good intrinsic capacity for timely payment of financial commitments.

F3: Fair Short-Term Credit Quality. The intrinsic capacity for timely payment of financial commitments is adequate.

B: Speculative Short-Term Credit Quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.

RD: Restricted Default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.

D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

Note: The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (‘AA+’; ‘AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings. For corporate finance obligation ratings, they are not appended to rating categories below the ‘CCC’. For all other sectors/obligations, they are not assigned to rating categories below the ‘B’.

The Board of Trustees/Directors of the Trust/Company (each series thereof, a “Fund”) have adopted the following policy and procedures with respect to voting proxies relating to portfolio securities held by the Trust/Company’s investment portfolios.

The policy of the Trust/Company is to delegate the responsibility for voting proxies relating to portfolio securities held by the Trust/Company to SSGA Funds Management, Inc., the Trust/Company’s investment adviser (the “Adviser”), subject to the Trustees/Directors’ continuing oversight.

The right to vote proxies with respect to a portfolio security held by the Trust/Company is an asset of the Trust/Company. The Adviser acts as a fiduciary of the Trust/Company and must vote proxies in a manner consistent with the best interest of the Trust/Company and its shareholders.

A. At least annually, the Adviser shall present to the Boards of Trustees/Directors its policies, procedures and other guidelines for voting proxies (“Policy”) and the policy of any Sub- adviser (as defined below) to which proxy voting authority has been delegated (see Section 9 below). In addition, the Adviser shall notify the Trustees/Directors of material changes to its Policy or the policy of any Sub – adviser promptly and not later than the next regular meeting of the Board of Trustees/Directors after such amendment is implemented.

B. At least annually, the Adviser shall present to the Boards of Trustees/Directors its policy for managing conflicts of interests that may arise through the Adviser’s proxy voting activities. In addition, the Adviser shall report any Policy overrides involving portfolio securities held by a Fund to the Trustees/Directors at the next regular meeting of the Board of Trustees/Directors after such override(s) occur.

C. At least annually, the Adviser shall inform the Trustees/Director that a record is available with respect to each proxy voted with respect to portfolio securities of the Trust/Company during the year. Also see Section 5 below.

The delegation by the Trustees/Directors of the authority to vote proxies relating to portfolio securities of the Trust/Company may be revoked by the Trustees/Directors, in whole or in part, at any time.

The Adviser shall provide the required data for each proxy voted with respect to portfolio securities of the Trust/Company to the Trust/Company or its designated service provider in a timely manner and in a format acceptable to be filed in the Trust/Company’s annual proxy voting report on Form N-PX for the twelve-month period ended June 30. Form N-PX is required to be filed not later than August 31 of each year.

A. In considering whether to retain or continue retaining a particular proxy advisory firm, the Adviser will ascertain whether the proxy advisory firm has the capacity and competency to adequately analyze proxy issues, act as proxy voting agent as requested, and implement the Policy. In this regard, the Adviser will consider, at least annually, among other things, the adequacy and quality of the proxy advisory firm’s staffing and personnel and the robustness of its policies and procedures regarding its ability to identify and address any conflicts of interest. The Adviser shall, at least annually, report to Boards of Trustees/Directors regarding the results of this review.

B. The Adviser will request quarterly and annual reporting from any proxy advisory firm retained by the Adviser, and hold ad hoc meetings with such proxy advisory firm, in order to determine whether there has been any business changes that might impact the proxy advisory firm’s capacity or competency to provide proxy voting advice or services or changes to the proxy advisory firm’s conflicts policies or procedures. The Adviser will also take reasonable steps to investigate any material factual error, notified to the Adviser by the proxy advisory firm or identified by the Adviser, made by the proxy advisory firm in providing proxy voting services.

The Adviser will periodically sample proxy votes to review whether they complied with the Policy. The Adviser shall, at least annually, report to the Boards of Trustees/Directors regarding the frequency and results of the sampling performed.

1. A description of this policy and of the policies and procedures used by the Adviser to determine how to vote proxies relating to portfolio securities; and

2. A statement disclosing that information regarding how the Trust/Company voted proxies relating to portfolio securities during the most recent twelve-month period ended June 30 is available without charge, upon request, by calling the Trust/Company’s toll-free telephone number; or through a specified Internet address; or both; and on the Securities and Exchange Commission’s (the “SEC”) website.

B. The Trust/Company shall include in its annual and semi-annual reports to shareholders:

1. A statement disclosing that a description of the policies and procedures used by or on behalf of the Trust/Company to determine how to vote proxies relating to portfolio securities of the Funds is available without charge, upon request, by calling the Trust/Company’s toll-free telephone number; through a specified Internet address, if applicable; and on the SEC’s website; and

For certain Funds, the Adviser may retain investment management firms (“Sub-advisers”) to provide day-to-day investment management services to the Funds pursuant to sub-advisory agreements. It is the policy of the Trust/Company that the Adviser may delegate proxy voting authority with respect to a Fund to a Sub-adviser. Pursuant to such delegation, a Sub-adviser is authorized to vote proxies on behalf of the applicable Fund or Funds for which it serves as sub-adviser, in accordance with the Sub-adviser’s proxy voting policies and procedures.

The Trustees/Directors shall review this policy to determine its continued sufficiency as necessary from time to time.

The SAI is not a prospectus and should be read in conjunction with the Prospectuses. A copy of each Prospectus can be obtained free of charge by calling (800) 647-7327 or by written request to the Trust at the address listed above.

The Trust was organized as a business trust under the laws of The Commonwealth of Massachusetts on February 16, 2000.

The Trust is an open-end management investment company. The Trust includes the following diversified series:

The Aggregate Bond Index Fund, the Emerging Markets Equity Index Fund, the Equity 500 Index Fund, the Global All Cap Equity ex-U.S. Index Fund, the Hedged International Developed Equity Index Fund, the International Developed Equity Index Fund and the Small/Mid Cap Equity Index Fund are referred to in this SAI as the “Index Funds.” The Retirement Fund, Target Retirement 2020 Fund, Target Retirement 2025 Fund, Target Retirement 2030 Fund, Target Retirement 2035 Fund, Target Retirement 2040 Fund, Target Retirement 2045 Fund, Target Retirement 2050 Fund, Target Retirement 2055 Fund, Target Retirement 2060 Fund and Target Retirement 2065 Fund are referred to collectively in this SAI as the “Target Retirement Funds.”

The Hedged International Developed Equity Index Fund seeks to gain its investment exposure to the constituents of the MSCI EAFE (Europe, Australasia, Far East) 100% Hedged to USD Index by investing in the International Developed Equity Index Portfolio. In managing its portfolio of investments, the Portfolio may purchase various securities and investment related instruments and make use of various investment techniques, including, but not limited to, those described below.

Effective October 9, 2019, the State Street Global Equity ex-U.S. Index Fund changed its name to State Street Global All Cap Equity ex-U.S. Index Fund.

In addition to the principal investment strategies and the principal risks of the Funds described in each Fund’s Prospectus, a Fund may employ other investment practices and may be subject to additional risks, which are described below. In reviewing these practices of the Feeder Funds, you should assume that the practices of the corresponding Portfolio are the same in all material respects.

Each Target Retirement Fund seeks to achieve its investment objective by investing in a combination of domestic and international mutual funds and exchange-traded funds sponsored by SSGA Funds Management, Inc. (the “Adviser” or “SSGA FM”) or its affiliates (“Underlying Funds”) using an asset allocation strategy. In managing their portfolios of investments, the Underlying Funds may purchase various securities and investment related instruments and make use of various investment techniques, including, but not limited to, those described below. Except as otherwise stated, references in this section to “the Funds,” “each Fund,” or “a Fund” may, as applicable, refer to the Funds, one or more Underlying Funds, or more than one of the foregoing.

Additional Information Concerning the MSCI All Country World Index ex USA Investable Market Index (the “MSCI ACWI ex USA IMI Index” or sometimes referred to in context as the “Index”)

The Global All Cap Equity ex-U.S. Index Fund is not sponsored, endorsed, sold or promoted by Morgan Stanley Capital International Inc. (“MSCI”). MSCI makes no representation or warranty, express or implied, to the owners of shares of the Global All Cap Equity ex-U.S. Index Fund or any member of the public regarding the advisability of investing in securities generally or in the Global All Cap Equity ex-U.S. Index Fund particularly or the ability of the MSCI Index to track general performance. MSCI’s only relationship to the Global All Cap Equity ex-U.S. Index Fund is the licensing of certain trademarks and trade names of MSCI and of the MSCI Index, which is determined, composed and calculated by MSCI without regard to the Global All Cap Equity ex-U.S. Index Fund. MSCI has no obligation to take the needs of the Global All Cap Equity ex-U.S. Index Fund or the owners of shares of the Global All Cap Equity ex-U.S. Index Fund into consideration in determining, composing or calculating the MSCI Index. MSCI is not responsible for and has not participated in the determination of the price and number of shares of the Global All Cap Equity ex-U.S. Index Fund or the timing of the issuance or sale of shares of Global All Cap Equity ex-U.S. Index Fund, or calculation of the equation by which shares of the Global All Cap Equity ex-U.S. Index Fund are redeemable for cash. MSCI has no obligation or liability in connection with the administration, marketing or trading of shares of the Global All Cap Equity ex-U.S. Index Fund.

MSCI does not guarantee the accuracy or the completeness of the MSCI Index or any data included therein and MSCI shall have no liability for any errors, omissions or interruptions therein. MSCI makes no warranty, express or implied, as to results to be obtained by the Global All Cap Equity ex-U.S. Index Fund, owners of shares of the Global All Cap Equity ex-U.S. Index Fund or any other person or entity from the use of the MSCI Index or any data included therein. MSCI makes no express or implied warranties, and expressly disclaims all warranties of merchantability or fitness for a particular purpose or use with respect to the MSCI Index or any data included therein. Without limiting any of the foregoing, in no event shall MSCI have any liability for any special, punitive, indirect or consequential damages (including lost profits), even if notified of the possibility of such damages.

An issuer may have the right to redeem or “call” a bond before maturity, in which case the investor may have to reinvest the proceeds at lower market rates. Most bonds bear interest income at a “coupon” rate that is fixed for the life of the bond. The value of a fixed rate bond usually rises when market interest rates fall, and falls when market interest rates rise. Accordingly, a fixed rate bond’s yield (income as a percent of the bond’s current value) may differ from its coupon rate as its value rises or falls. Fixed rate bonds generally are also subject to inflation risk, which is the risk that the value of the bond or income from the bond will be worth less in the future as inflation decreases the value of money. This could mean that, as inflation increases, the “real” value of the assets of a Fund holding fixed rate bonds can decline, as can the value of the Fund’s distributions. Other types of bonds bear income at an interest rate that is adjusted periodically. Because of their adjustable interest rates, the value of “floating-rate” or “variable-rate” bonds fluctuates much less in response to market interest rate movements than the value of fixed rate bonds. A Fund may treat some of these bonds as having a shorter maturity for purposes of calculating the weighted average maturity of its investment portfolio. Bonds may be senior or subordinated obligations. Senior obligations generally have the first claim on a corporation’s earnings and assets and, in the event of liquidation, are paid before subordinated obligations. Bonds may be unsecured (backed only by the issuer’s general creditworthiness) or secured (also backed by specified collateral). The investment return of corporate bonds reflects interest on the bond and changes in the market value of the bond. The market value of a corporate bond may be affected by the credit rating of the corporation, the corporation’s performance and perceptions of the corporation in the market place. There is a risk that the issuers of the securities may not be able to meet their obligations on interest or principal payments at the time called for by such a security.

Each Fund may hold portions of its assets in cash or short-term debt instruments with remaining maturities of 397 days or less pending investment or to meet anticipated redemptions and day-to-day operating expenses. Short-term debt instruments consist of: (i) short-term obligations of the U.S. Government, its agencies, instrumentalities, authorities or political subdivisions; (ii) other short-term debt securities rated at the time of purchase Aa or higher by Moody’s Investors Service, Inc. (“Moody’s”) or AA or higher by S&P or, if unrated, of comparable quality in the opinion of SSGA FM; (iii) commercial paper; (iv) bank obligations, including negotiable certificates of deposit, time deposits and bankers’ acceptances; and (v) repurchase agreements.

Counterparty risk with respect to derivatives has been and will continue to be affected by new rules and regulations relating to the derivatives market. With respect to a centrally cleared transaction, a party is subject to the credit risk of the clearing house and the clearing member through which it holds its cleared position. Credit risk of market participants with respect to centrally cleared derivatives is concentrated in a few clearing houses, and it is not clear how an insolvency proceeding of a clearing house would be conducted and what impact an insolvency of a clearing house would have on the financial system. A clearing member is obligated by contract and regulation to segregate all funds received from customers with respect to cleared derivatives positions from the clearing member’s proprietary assets. However, all funds and other property received by a clearing member from its customers with respect to cleared derivatives are generally held by the clearing member on a commingled basis in an omnibus account (which can be invested in instruments permitted under the regulations). Therefore, a Fund might not be fully protected in the event of the bankruptcy of the Fund’s clearing member because the Fund would be limited to recovering only a pro rata share of the funds held by the clearing member on behalf of customers, with a claim against the clearing member for any deficiency. Also, the clearing member is required to transfer to the clearing house the amount of margin required by the clearing house for cleared derivatives, which amount is generally held in an omnibus account at the clearing house for all customers of the clearing member. Regulations promulgated by the Commodity Futures Trading Commission (the “CFTC”) require that the clearing member notify the clearing house of the initial margin provided by the clearing member to the clearing house that is attributable to each customer. However, if the clearing member does not accurately report the Fund’s initial margin, the Fund is subject to the risk that a clearing house will use the assets attributable to it in the clearing house’s omnibus account to satisfy payment obligations a defaulting customer of the clearing member has to the clearing house. In addition, clearing members generally provide the clearing house the net amount of variation margin required for cleared swaps for all of its customers, rather than individually for each customer. A Fund is therefore subject to the risk that a clearing house will not make variation margin payments owed to the Fund if another customer of the clearing member has suffered a loss and is in default, and the risk that the Fund will be required to provide additional variation margin to the clearing house before the clearing house will move the Fund’s cleared derivatives positions to another clearing member. In addition, if a clearing member does not comply with the applicable regulations or its agreement with the Fund, or in the event of fraud or misappropriation of customer assets by a clearing member, the Fund could have only an unsecured creditor claim in an insolvency of the clearing member with respect to the margin held by the clearing member.

Certain derivatives contracts are required to be executed through swap execution facilities (“SEFs”). A SEF is a trading platform where multiple market participants can execute derivatives by accepting bids and offers made by multiple other participants in the platform. Such requirements may make it more difficult and costly for investment funds, such as a Fund, to enter into highly tailored or customized transactions. Trading swaps on a SEF may offer certain advantages over traditional bilateral over-the-counter trading, such as ease of execution, price transparency, increased liquidity and/or favorable pricing. Execution through a SEF is not, however, without additional costs and risks, as parties are required to comply with SEF and CFTC rules and regulations, including disclosure and recordkeeping obligations, and SEF rights of inspection, among others. SEFs typically charge fees, and if a Fund executes derivatives on a SEF through a broker intermediary, the intermediary may impose fees as well. A Fund also may be required to indemnify a SEF, or a broker intermediary who executes swaps on a SEF on the Fund’s behalf, against any losses or costs that may be incurred as a result of the Fund’s transactions on the SEF. In addition, a Fund may be subject to execution risk if it enters into a derivatives transaction that is required to be cleared, and no clearing member is willing to clear the transaction on the Fund’s behalf. In that case, the transaction might have to be terminated, and the Fund could lose some or all of the benefit of any increase in the value of the transaction after the time of the trade.

A Fund’s ability to invest in commodity-linked investments may be limited by the Fund’s intention to qualify as a regulated investment company (“RIC”) under the Internal Revenue Code of 1986, as amended (the “Code”) and could bear on the ability of a Fund to so qualify. See “Taxation of the Funds” below.

Commodity-Linked Investments. The Funds may invest in commodity-linked investments. The Funds may seek to provide exposure to the investment returns of real assets that trade in the commodity markets through commodity-linked derivative securities, such as structured notes, discussed below, which are designed to provide this exposure without direct investment in physical commodities or commodities futures contracts. Real assets are assets such as oil, gas, industrial and precious metals, livestock, and agricultural or meat products, or other items that have tangible properties, as compared to stocks or bonds, which are financial instruments. In choosing investments, the Adviser seeks to provide exposure to various commodities and commodity sectors. The value of commodity-linked derivative securities held by a Fund may be affected by a variety of factors, including, but not limited to, overall market movements and other factors affecting the value of particular industries or commodities, such as weather, disease, embargoes, acts of war or terrorism, or political and regulatory developments.

The prices of commodity-linked derivative securities may move in different directions than investments in traditional equity and debt securities when the value of those traditional securities is declining due to adverse economic conditions. As an example, during periods of rising inflation, debt securities have historically tended to decline in value due to the general increase in prevailing interest rates. Conversely, during those same periods of rising inflation, the prices of certain commodities, such as oil and metals, have historically tended to increase. Of course, there cannot be any guarantee that these investments will perform in that manner in the future, and at certain times the price movements of commodity-linked instruments have been parallel to those of debt and equity securities. Commodities have historically tended to increase and decrease in value during different parts of the business cycle than financial assets. Nevertheless, at various times, commodities prices may move in tandem with the prices of financial assets and thus may not provide overall portfolio diversification benefits. Under favorable economic conditions, a Fund’s investments may be expected to underperform an investment in traditional securities. Over the long term, the returns on the Fund’s investments are expected to exhibit low or negative correlation with stocks and bonds.

Because commodity-linked investments are available from a relatively small number of issuers, a Fund’s investments will be particularly subject to counterparty risk, which is the risk that the issuer of the commodity-linked derivative (which issuer may also serve as counterparty to a substantial number of the Fund’s commodity-linked and other derivative investments) will not fulfill its contractual obligations.

A Fund’s ability to invest in commodity-linked investments may be limited by the Fund’s intention to qualify as a RIC and could bear on the ability of a Fund to so qualify. See “Taxation of the Funds” below.

The Funds may enter into credit default swaps or total return swaps to gain market exposure, manage liquidity, increase total returns or for hedging purposes. Credit default swaps and total return swaps are typically governed by the standard terms and conditions of an ISDA Master Agreement.

In both credit default swaps and total return swaps, the same general risks inherent to derivative transactions are present; however, the use of credit default swaps and total return swaps can involve greater risks than if the Funds had invested in the reference obligation directly since, in addition to general market risks, credit default swaps and total return swaps are subject to counterparty credit risk, leverage risk, hedging risk, correlation risk and liquidity risk. The Funds will enter into credit default swap or a total return swap only with counterparties that the Adviser determines to meet certain standards of creditworthiness. In a credit default swap, a buyer generally also will lose its premium and recover nothing should no credit event occur and the swap is held to its termination date. If a credit event were to occur, the value of any deliverable obligation received by the seller, coupled with the upfront or periodic payments previously received, may be less than the full notional value it pays to the buyer, resulting in a loss of value to the seller. A Fund’s obligations under a credit default swap agreement will be accrued daily (offset against any amounts owing to the Fund).

Swaps are highly specialized instruments that require investment techniques, risk analyses, and tax planning different from those associated with the ownership of stocks, bonds, and other traditional investments. The use of a swap agreement requires an understanding not only of the referenced obligation, reference rate, or index, but also of the swap agreement itself. Because some swap agreements have a leverage component, adverse changes in the value or level of the underlying asset, reference rate, or index can result in a loss substantially greater than the amount invested in the swap itself. Certain swaps have the potential for unlimited loss, regardless of the size of the initial investment.

A Fund’s exposure under a credit default swap may be considered leverage and as such be subject to the restrictions on leveraged derivatives.

There are risks involved in dealing with the custodians or brokers who hold a Fund’s investments or settle a Fund’s trades. It is possible that, in the event of the insolvency or bankruptcy of a custodian or broker, a Fund would be delayed or prevented from recovering its assets from the custodian or broker, or its estate, and may have only a general unsecured claim against the custodian or broker for those assets. In recent insolvencies of brokers or other financial institutions, the ability of certain customers to recover their assets from the insolvent’s estate has been delayed, limited, or prevented, often unpredictably, and there is no assurance that any assets held by a Fund with a custodian or broker will be readily recoverable by the Fund. In addition, there may be limited recourse against non-U.S. sub-custodians in those situations in which a Fund invests in markets where custodial and/or settlement systems and regulations are not fully developed, including emerging markets, and the assets of the Fund have been entrusted to such sub-custodians. SSGA FM or an affiliate may serve as the custodian of the Funds.

Eurodollar Certificates of Deposit (“ECDs”), Eurodollar Time Deposits (“ETDs”) and Yankee Certificates of Deposit (“YCDs”)

The Funds may invest in ECDs, ETDs and YCDs. ECDs and ETDs are U.S. dollar denominated certificates of deposit and time deposits, respectively, issued by non-U.S. branches of domestic banks and non-U.S. banks. YCDs are U.S. dollar denominated certificates of deposit issued by U.S. branches of non-U.S. banks.

Different risks than those associated with the obligations of domestic banks may exist for ECDs, ETDs and YCDs because the banks issuing these instruments, or their domestic or non-U.S. branches, are not necessarily subject to the same regulatory requirements that apply to domestic banks, such as loan limitations, examinations and reserve, accounting, auditing, recordkeeping and public reporting requirements. Obligations of non-U.S. issuers also involve risks such as future unfavorable political and economic developments, withholding or other taxes, seizures of non-U.S. deposits, currency controls, interest limitations, and other governmental restrictions that might affect repayment of principal or payment of interest, or the ability to honor a credit commitment.

The Funds may enter into a variety of different foreign currency transactions, including, by way of example, currency forward transactions, spot transactions, futures and forward contracts, swaps, or options. Most of these transactions are entered into “over the counter,” and a Fund assumes the risk that the counterparty may be unable or unwilling to perform its obligations, in addition to the risk of unfavorable or unanticipated changes in the values of the currencies underlying the transactions. Certain types of over-the-counter currency transactions may be uncollateralized, and a Fund may not be able to recover all or any of the assets owed to it under such transactions if its counterparty should default. In some markets or in respect of certain currencies, a Fund may be required, or agree, in SSGA FM’s discretion, to enter into foreign currency transactions via the custodian’s relevant sub-custodian. SSGA FM may be subject to a conflict of interest in agreeing to any such arrangements on behalf of a Fund. Such transactions executed directly with the sub-custodian are executed at a rate determined solely by such sub-custodian. Accordingly, a Fund may not receive the best pricing of such currency transactions. Regulatory changes in a number of jurisdictions may require that certain currency transactions be subject to central clearing, or be subject to new or increased collateral requirements. These changes could increase the costs of currency transactions to a Fund and may make certain transactions unavailable; they may also increase the credit risk of such transactions to a Fund.

The Funds are permitted to invest in foreign securities. Foreign securities include securities of foreign companies and foreign governments (or agencies or subdivisions thereof). If a Fund’s securities are held abroad, the countries in which such securities may be held and the sub-custodian holding them must be approved by the Board of Trustees of the Trust (the “Board of Trustees” or the “Board”) or its delegate under applicable rules adopted by the Securities and Exchange Commission (“SEC”). In buying foreign securities, the Fund may convert U.S. dollars into foreign currency, but only to effect securities transactions on foreign securities exchanges and not to hold such currency as an investment.

The globalization and integration of the world economic system and related financial markets have made it increasingly difficult to define issuers geographically. Accordingly, each Fund intends to construe geographic terms such as “foreign,” “non-U.S.” “European,” “Latin American,” and “Asian,” in the manner that affords to the Fund the greatest flexibility in seeking to achieve its investment objective(s). Specifically, in circumstances where the investment objective and/or strategy is to invest at least some percentage of the Fund’s assets in foreign securities, etc., the Funds will take the view that a security meets this description so long as the issuer of a security is tied economically to the particular country or geographic region indicated by words of the relevant investment objective and/or strategy (the “Relevant Language”). For these purposes the issuer of a security is deemed to have that tie if:

(i) The issuer is organized under the laws of the country or a country within the geographic region suggested by the Relevant Language or maintains its principal place of business in that country or region; or

(ii) The securities are traded principally in the country or region suggested by the Relevant Language; or

(iii) The issuer, during its most recent fiscal year, derived at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed in the country or region suggested by the Relevant Language or has at least 50% of its assets in that country or region.

In addition, the Funds intend to treat derivative securities (e.g., call options) by reference to the underlying security. Conversely, if the investment objective and/or strategy of the Fund limits the percentage of assets that may be invested in “foreign securities,” etc. or prohibits such investments altogether, the Funds intend to categorize securities as “foreign,” etc. only if the security possesses all of the attributes described above in clauses (i), (ii) and (iii).

A number of current significant political, demographic and economic developments may affect investments in foreign securities and in securities of companies with operations overseas. Such developments include dramatic political changes in government and economic policies in several Eastern European countries and the republics composing the former Soviet Union, as well as the unification of the European Economic Community. The course of any one or more of these events and the effect on trade barriers, competition and markets for consumer goods and services are uncertain. Similar considerations are of concern with respect to developing countries. For example, the possibility of revolution and the dependence on foreign economic assistance may be greater in these countries than in developed countries. Management seeks to mitigate the risks associated with these considerations through diversification and active professional management.

Each Fund may enter into futures contracts on securities in which it may invest or on indices comprised of such securities and may purchase and write call and put options on such contracts.

Although many futures contracts by their terms call for actual delivery or acceptance of commodities or securities, in most cases the contracts are closed out before the settlement date without the making or taking of delivery, but rather by entering into an offsetting contract (a “closing transaction”). Upon entering into a futures contract, a Fund is required to deposit initial margin with the futures broker. The initial margin serves as a “good faith” deposit that a Fund will honor its potential future commitments. Subsequent payments (called “variation margin” or “maintenance margin”) to and from the broker are made on a daily basis as the price of the underlying security or commodity fluctuates, making the long and short positions in the futures contract more or less valuable, a process known as “marking to the market.” If a Fund is unable to enter into a closing transaction, the amount of the Fund’s potential loss may be unlimited. Futures contracts also involve brokerage costs.

Each Fund will not commit more than 5% of the market value of its total assets to initial margin deposits on futures and premiums paid for options on futures.

Under this exclusion, a Fund must satisfy one of the following two trading limitations whenever it enters into a new commodity trading position: (1) the aggregate initial margin and premiums required to establish the Fund’s positions in CFTC-regulated instruments may not exceed 5% of the liquidation value of the Fund’s portfolio (after accounting for unrealized profits and unrealized losses on any such investments); or (2) the aggregate net notional value of such instruments, determined at the time the most recent position was established, may not exceed 100% of the liquidation value of the Fund’s portfolio (after accounting for unrealized profits and unrealized losses on any such positions). A Fund would not be required to consider its exposure to such instruments if they were held for “bona fide hedging” purposes, as such term is defined in the rules of the CFTC. In addition to meeting one of the foregoing trading limitations, the Fund may not market itself as a commodity pool or otherwise as a vehicle for trading in the markets for CFTC-regulated instruments.

As with options on securities, the holder or writer of an option may terminate his position by selling or purchasing an offsetting option. There is no guarantee that such closing transactions can be effected.

A Fund will be required to deposit initial margin and maintenance margin with respect to put and call options on futures contracts written by it pursuant to brokers’ requirements similar to those described above in connection with the discussion of futures contracts.

Risks of transactions in futures contracts and related options. Successful use of futures contracts by a Fund is subject to the Adviser’s ability to predict movements in various factors affecting financial markets. Compared to the purchase or sale of futures contracts, the purchase of call or put options on futures contracts involves less potential risk to a Fund because the maximum amount at risk is the premium paid for the options (plus transaction costs). However, there may be circumstances when the purchase of a call or put option on a futures contract would result in a loss to a Fund when the purchase or sale of a futures contract would not, such as when there is no movement in the prices of the hedged investments. The writing of an option on a futures contract involves risks similar to those risks relating to the sale of futures contracts.

The use of options and futures strategies involves the risk of imperfect correlation among movements in the prices of the securities underlying the futures and options purchased and sold by the Fund, of the options and futures contracts themselves, and, in the case of hedging transactions, of the securities which are the subject of a hedge. The successful use of these strategies further depends on the ability of the Adviser to forecast interest rates and market movements correctly.

There is no assurance that higher than anticipated trading activity or other unforeseen events might not, at times, render certain market clearing facilities inadequate, and thereby result in the institution by exchanges of special procedures which may interfere with the timely execution of customer orders.

Successful use of U.S. Treasury security futures contracts by a Fund is subject to the Adviser’s ability to predict movements in the direction of interest rates and other factors affecting markets for debt securities. For example, if a Fund has sold U.S. Treasury security futures contracts in order to hedge against the possibility of an increase in interest rates which would adversely affect the values of securities held in its portfolio, and the prices of the Fund’s securities increase instead as a result of a decline in interest rates, the Fund will lose part or all of the benefit of the increased value of its securities which it has hedged because it will have offsetting losses in its futures positions. In addition, in such situations, if the Fund has insufficient cash, it may have to sell securities to meet daily maintenance margin requirements at a time when it may be disadvantageous to do so.

There is also a risk that price movements in U.S. Treasury security futures contracts and related options will not correlate closely with price movements in markets for particular securities. For example, if a Fund has hedged against a decline in the values of tax-exempt securities held by it by selling Treasury security futures and the values of Treasury securities subsequently increase while the values of the Fund’s tax-exempt securities decrease, the Fund would incur losses on both the Treasury security futures contracts written by it and the tax-exempt securities held in its portfolio.

The Funds may invest a portion of their assets in high yield debt securities (commonly known as “junk bonds”). Investment in high yield securities generally provides greater income and increased opportunity for capital appreciation than investments in higher quality securities, but they also typically entail greater price volatility and credit risk. These high yield securities are regarded as predominantly speculative with respect to the issuer’s continuing ability to meet principal and interest payments. Analysis of the creditworthiness of issuers of debt securities that are high yield may be more complex than for issuers of higher quality debt securities. In addition, high yield securities are often issued by smaller, less creditworthy companies or by highly leveraged (indebted) firms, but can also be issued by governments. Such issuers are generally less able than more financially stable issuers to make scheduled payments of interest and principal. The risks posed by securities issued under such circumstances are substantial.

Furthermore, the value of high yield securities may be more susceptible to real or perceived adverse economic, company or industry conditions than is the case for higher quality securities. The market values of certain of these lower-rated and unrated debt securities tend to reflect individual issuer developments to a greater extent than do higher-rated securities which react primarily to fluctuations in the general level of interest rates, and tend to be more sensitive to economic conditions than are higher-rated securities. Adverse market, credit or economic conditions could make it difficult at certain times to sell certain high yield securities held by a Fund.

The secondary market on which high yield securities are traded may be less liquid than the market for higher grade securities. Less liquidity in the secondary trading market could adversely affect the price at which a Fund could sell a high yield security, and could adversely affect the daily net asset value (“NAV”) per share of a Fund. When secondary markets for high yield securities are less liquid than the market for higher grade securities, it may be more difficult to value the securities because there is less reliable, objective data available. However, an Index seeks to include primarily high yield securities that the Index provider believes have greater liquidity than the broader high yield securities market as a whole.

The use of credit ratings as a principal method of selecting high yield securities can involve certain risks. For example, credit ratings evaluate the safety of principal and interest payments, not the market value risk of high yield securities. Also, credit rating agencies may fail to change credit ratings in a timely fashion to reflect events since the security was last rated.

Each Fund may invest in illiquid securities. Each Fund will invest no more than 15% of its net assets in illiquid securities, including repurchase agreements and time deposits of more than seven days’ duration. The absence of a regular trading market for illiquid securities imposes additional risks on investments in these securities. Illiquid securities may be difficult to value and may often be disposed of only after considerable expense and delay.

The SEC has adopted a liquidity risk management rule (the “Liquidity Rule”) that requires the Funds to establish a liquidity risk management program (the “LRMP”). The Trustees, including a majority of the Independent Trustees (defined infra), have designated the Adviser to administer the Funds’ LRMP. Under the LRMP, the Adviser assesses, manages, and periodically reviews the Funds’ liquidity risk. The Liquidity Rule defines “liquidity risk” as the risk that the Funds could not meet requests to redeem shares issued by the Funds without significant dilution of remaining investors’ interests in the Funds. The liquidity of the Funds’ portfolio investments is determined based on relevant market, trading and investment-specific considerations under the LRMP. To the extent that an investment is deemed to be an illiquid investment or a less liquid investment, the Funds can expect to be exposed to greater liquidity risk. The Liquidity Rule’s impact on a Fund, and on the open-end fund industry in general, is not yet fully known, but the rule could affect a Fund’s performance and its ability to achieve its investment objectives. While the liquidity risk management program attempts to assess and manage liquidity risk, there is no guarantee it will be effective in its operations and may not reduce the liquidity risk inherent in a Fund’s investments.

Infrastructure-related companies include companies that primarily own, manage, develop and/or operate infrastructure assets, including transportation, utility, energy and/or telecommunications assets. Infrastructure-related businesses are subject to a variety of factors that may adversely affect their business or operations, including high interest costs in connection with capital construction programs, insurance costs, costs associated with environmental and other regulations, the effects of an economic slowdown, surplus capacity or technological obsolescence, industry competition, labor relations, rate caps or rate changes, uncertainties concerning availability of fuel at reasonable prices, the effects of energy conservation policies, natural disasters, terrorist attacks and other factors. Certain infrastructure-related entities, particularly telecommunications and utilities companies, are subject to extensive regulation by various governmental authorities. The costs of complying with governmental regulations, delays or failures to receive required regulatory approvals or the enactment of new adverse regulatory requirements may adversely affect infrastructure-related companies. Infrastructure-related companies may also be affected by service interruption and/or legal challenges due to environmental, operational or other conditions or events, and the imposition of special tariffs and changes in tax laws, regulatory policies and accounting standards. There is also the risk that corruption may negatively affect publicly-funded infrastructure projects, especially in non-U.S. markets, resulting in work stoppage, delays and cost overruns. Other risks associated with infrastructure-related companies include uncertainties resulting from such companies’ diversification into new domestic and international businesses, as well as agreements by any such companies linking future rate increases to inflation or other factors not directly related to the actual operating profits of the enterprise.

The Funds may invest in corporate notes and bonds that are rated investment-grade by a nationally recognized statistical rating organization (“NRSRO”) or, if unrated, are of comparable quality to the rated securities described above, as determined by the Adviser, in accordance with procedures established by the Board of Trustees. Investment-grade securities include securities rated Baa or higher by Moody’s or BBB- or higher by S&P (and securities of comparable quality); securities rated Baa by Moody’s or BBB by S&P may have speculative characteristics.

Each Fund may lend portfolio securities to certain creditworthy borrowers in U.S. and non-U.S. markets in an amount not to exceed 40% of the value of its net assets. The borrowers provide collateral that is marked to market daily in an amount at least equal to the current market value of the securities loaned. A Fund may terminate a loan at any time and obtain the securities loaned. A Fund

receives the value of any interest or cash or non-cash distributions paid on the loaned securities. A Fund cannot vote proxies for securities on loan, but may recall loans to vote proxies if a material issue affecting the Fund’s economic interest in the investment is to be voted upon. Efforts to recall such securities promptly may be unsuccessful, especially for foreign securities or thinly traded securities, and may involve expenses to a Fund. Distributions received on loaned securities in lieu of dividend payments (i.e., substitute payments) would not be considered qualified dividend income.

With respect to loans that are collateralized by cash, the borrower typically will be entitled to receive a fee based on the amount of cash collateral. A Fund is compensated by the difference between the amount earned on the reinvestment of cash collateral and the fee paid to the borrower. In the case of collateral other than cash, a Fund is compensated by a fee paid by the borrower equal to a percentage of the market value of the loaned securities. Any cash collateral may be reinvested in certain high quality short-term instruments either directly on behalf of the lending Fund or through one or more joint accounts or funds, which may include those managed by the Adviser. A Fund could lose money due to a decline in the value of collateral provided for loaned securities or any investments made with cash collateral.

A Fund may pay a portion of the interest or fees earned from securities lending to a borrower as described above, and to one or more securities lending agents approved by the Board of Trustees of the Trust (the “Board”) who administer the lending program for the Funds in accordance with guidelines approved by the Board. In such capacity, the lending agent provides the following services to the Funds in connection with the Funds’ securities lending activities: (i) locating borrowers among an approved list of prospective borrowers; (ii) causing the delivery of loaned securities from a Fund to borrowers; (iii) monitoring the value of loaned securities, the value of collateral received, and other lending parameters; (iv) seeking additional collateral, as necessary, from borrowers; (v) receiving and holding collateral from borrowers, and facilitating the investment and reinvestment of all or substantially all cash collateral in an investment vehicle designated by the Funds; (vi) returning collateral to borrowers; (vii) facilitating substitute dividend, interest, and other distribution payments to the Funds from borrowers; (viii) negotiating the terms of each loan of securities, including but not limited to the amount of any loan premium, and monitoring the terms of securities loan agreements with prospective borrowers for consistency with the requirements of the Funds’ Securities Lending Authorization Agreement; (ix) selecting securities, including amounts (percentages), to be loaned; (x) recordkeeping and accounting servicing; and (xi) arranging for return of loaned securities to the Fund in accordance with the terms of the Securities Lending Authorization Agreement. State Street Bank and Trust Company (“State Street”), an affiliate of the Trust, has been approved by the Board to serve as securities lending agent for each Fund and the Trust has entered into an agreement with State Street for such services. Among other matters, the Trust has agreed to indemnify State Street for certain liabilities. State Street has received an order of exemption from the SEC under Sections 17(a), 17(d) and 12(d)(1) under the 1940 Act to serve as the lending agent for affiliated investment companies such as the Trust, to invest the cash collateral received from loan transactions in an affiliated cash collateral fund and to receive a fee based on a share of the revenue generated from such transactions.

Securities lending involves exposure to certain risks, including operational risk (i.e., the risk of losses resulting from problems in the settlement and accounting process especially so in certain international markets such as Taiwan), “gap” risk (i.e., the risk of a mismatch between the return on cash collateral reinvestments and the fees a Fund has agreed to pay a borrower), risk of loss of collateral, credit, legal, counterparty and market risk. If a securities lending counterparty were to default, a Fund would be subject to the risk of a possible delay in receiving collateral (or the proceeds of its liquidation) or in recovering the loaned securities. In the event a borrower does not return a Fund’s securities as agreed, the Fund may experience losses if the proceeds received from liquidating the collateral do not at least equal the value of the loaned security at the time the collateral is liquidated, plus the transaction costs incurred in purchasing replacement securities. Although State Street has agreed to provide a Fund with indemnification in the event of a borrower default, a Fund is still exposed to the risk of losses in the event a borrower does not return a Fund’s securities as agreed. For example, delays in recovery of lent securities may cause a Fund to lose the opportunity to sell the securities at a desirable price with guaranteed delivery provisions.

industries more dramatically than others, which may adversely affect the value of a Fund’s investments in those sectors or industries. COVID-19, and other epidemics and pandemics that may arise in the future, could adversely affect the economies of many nations, the global economy, individual companies and capital markets in ways that cannot be foreseen at the present time. In addition, the impact of infectious diseases in developing or emerging market countries may be greater due to limited health care resources. Political, economic and social stresses caused by COVID-19 also may exacerbate other pre-existing political, social and economic risks in certain countries. The duration of COVID-19 and its effects cannot be determined at this time, but the effects could be present for an extended period of time.

The Funds, except for the Emerging Markets Equity Index Fund and the Small/Mid Cap Equity Index Fund, may enter into “forward roll” transactions with respect to mortgage-related securities issued by GNMA, FNMA or FHLMC. In a forward roll transaction, a Fund will sell a mortgage-related security to a bank or other permitted entity and simultaneously agree to repurchase a similar security from the institution at a later date at an agreed upon price. The mortgage securities that are repurchased will typically bear the same interest rate as those sold, but generally will be collateralized by different pools of mortgages with different prepayment histories than those sold. A Fund that engages in a forward roll transaction forgoes principal and interest paid on the securities sold during the roll period, but is compensated by the difference between the current sales price and the lower forward price for the future purchase. In addition, a Fund earns interest by investing the transaction proceeds during the roll period. A forward roll transaction may create investment leverage. A Fund is subject to the risk that the value of securities to be purchased pursuant to a forward roll transaction will decline over the roll period, and that the Fund’s counterparty may be unwilling or unable to perform its obligations to the Fund. Upon entering into a mortgage-backed security roll, the participating Fund will segregate on its records cash, U.S. Government securities or other high-grade debt securities in an amount sufficient to cover its obligation under the roll.

The Funds, except for the Emerging Markets Equity Index Fund, may invest in mortgage-related securities. Mortgage-related securities represent an interest in a pool of, or are secured by, mortgage loans. Mortgage-related securities may be issued or guaranteed by (i) U.S. Government agencies or instrumentalities such as GNMA, FNMA and FHLMC or (ii) other issuers, including private companies.

Stripped mortgage-related securities are usually structured with two classes that receive different portions of the interest and principal distributions on a pool of mortgage loans. The yield to maturity on an interest only or “IO” class of stripped mortgage-related securities is extremely sensitive not only to changes in prevailing interest rates but also to the rate of principal payments (including prepayments) on the underlying assets. A rapid rate of principal prepayments may have a measurable adverse effect on a Fund’s yield to maturity to the extent it invests in IOs. If the assets underlying the IO experience greater than anticipated prepayments of principal, the Fund may fail to recoup fully, or at all, its initial investment in these securities. Conversely, principal only securities or “POs” tend to increase in value if prepayments are greater than anticipated and decline if prepayments are slower than anticipated. The secondary market for stripped mortgage-related securities may be more volatile and less liquid than that for other mortgage-related securities, potentially limiting a Fund’s ability to buy or sell those securities at any particular time.

The Funds may purchase and sell put and call options to enhance investment performance and to protect against changes in market prices. There is no assurance that a Fund’s use of put and call options will achieve its desired objective, and a Fund’s use of options may result in losses to the Fund.

Covered call options. A Fund may write (i.e., sell) covered call options to realize a greater current return through the receipt of premiums than it would realize on its securities alone. Such option transactions may also be used as a limited form of hedging against a decline in the price of securities owned by a Fund.

A call option gives the holder the right to purchase, and obligates the writer to sell, a security at the exercise price at any time before the expiration date. A call option is “covered” if the writer, at all times while obligated as a writer, either owns the underlying securities (or comparable securities satisfying the cover requirements of the securities exchanges), or has the right to acquire such securities through immediate conversion of securities. A Fund may write covered call options or uncovered call options.

A Fund will receive a premium from writing a call option, which increases the Fund’s return on the underlying security in the event the option expires unexercised or is closed out at a profit. The amount of the premium reflects, among other things, the relationship between the exercise price and the current market value of the underlying security, the volatility of the underlying security, the amount of time remaining until expiration, current interest rates, and the effect of supply and demand in the options market and in the market for the underlying security.

In return for the premium received when it writes a covered call option, a Fund gives up some or all of the opportunity to profit from an increase in the market price of the securities covering the call option during the life of the option. A Fund retains the risk of loss should the price of such securities decline. If the option expires unexercised, a Fund realizes a gain equal to the premium, which may be offset by a decline in price of the underlying security. If the option is exercised, a Fund realizes a gain or loss equal to the difference between the Fund’s cost for the underlying security and the proceeds of sale (exercise price minus commissions) plus the amount of the premium.

A Fund may terminate a call option that it has written before it expires by entering into a closing purchase transaction. A Fund may enter into closing purchase transactions in order to free itself to sell the underlying security or to write another call on the security, realize a profit on a previously written call option, or protect a security from being called in an unexpected market rise. Any profits from a closing purchase transaction may be offset by a decline in the value of the underlying security. Conversely, because increases in the market price of a call option will generally reflect increases in the market price of the underlying security, any loss resulting from a closing purchase transaction is likely to be offset in whole or in part by unrealized appreciation of the underlying security owned by a Fund.

Uncovered call options. Writing uncovered call options may enable a Fund to realize income without committing capital to the ownership of the underlying securities or instruments, however writing uncovered calls are riskier than writing covered calls because there is no underlying security held by a Fund that can act as a partial hedge. When a Fund has written an uncovered call option, the Fund will not necessarily hold securities offsetting the risk to the Fund. As a result of writing a call option without holding the underlying the securities, if the call option were exercised, a Fund might be required to purchase the security that is the subject of the call at the market price at the time of exercise. The Fund’s exposure on such an option is theoretically unlimited. There is also a risk, especially with less liquid preferred and debt securities, that the security may not be available for purchase. Uncovered calls have speculative characteristics.

Covered put options. A Fund may write covered put options in order to enhance its current return. Such options transactions may also be used as a limited form of hedging against an increase in the price of securities that the Fund plans to purchase. A put option gives the holder the right to sell, and obligates the writer to buy, a security at the exercise price at any time before the expiration date. A put option may be “covered” if the writer earmarks or otherwise segregates liquid assets equal to the price to be paid if the option is exercised minus margin on deposit.

By writing a put option, a Fund assumes the risk that it may be required to purchase the underlying security for an exercise price higher than its then current market value, resulting in a potential capital loss unless the security later appreciates in value.

A Fund may terminate a put option that it has written before it expires by entering into a closing purchase transaction. Any loss from this transaction may be partially or entirely offset by the premium received on the terminated option.

Purchasing put and call options. A Fund may also purchase put options to protect portfolio holdings against a decline in market value. This protection lasts for the life of the put option because a Fund, as a holder of the option, may sell the underlying security at the exercise price regardless of any decline in its market price. In order for a put option to be profitable, the market price of the underlying security must decline sufficiently below the exercise price to cover the premium and transaction costs that a Fund must pay. These costs will reduce any profit the Fund might have realized had it sold the underlying security instead of buying the put option.

A Fund may purchase call options to hedge against an increase in the price of securities that the Fund wants ultimately to buy. Such hedge protection is provided during the life of the call option since a Fund, as holder of the call option, is able to buy the underlying security at the exercise price regardless of any increase in the underlying security’s market price. In order for a call option to be profitable, the market price of the underlying security must rise sufficiently above the exercise price to cover the premium and transaction costs. These costs will reduce any profit a Fund might have realized had it bought the underlying security at the time it purchased the call option.

A Fund may also purchase put and call options to attempt to enhance its current return.

Options on foreign securities. A Fund may purchase and sell options on foreign securities if the Adviser believes that the investment characteristics of such options, including the risks of investing in such options, are consistent with the Fund’s investment objective. It is expected that risks related to such options will not differ materially from risks related to options on U.S. securities. However, position limits and other rules of foreign exchanges may differ from those in the United States. In addition, options markets in some countries, many of which are relatively new, may be less liquid than comparable markets in the United States.

Options on securities indices. A Fund may write or purchase options on securities indices. Index options are similar to options on individual securities in that the purchaser of an index option acquires the right to buy (in the case of a call) or sell (in the case of a put), and the writer undertakes the obligation to sell or buy (as the case may be), units of an index at a stated exercise price during the term of the option. Instead of the right to take or make actual delivery of securities, the holder of an index option has the right to receive a cash “exercise settlement amount.” This amount is equal to the amount by which the fixed exercise price of the option exceeds (in the case of a put) or is less than (in the case of a call) the closing value of the underlying index on the date of the exercise, multiplied by a fixed “index multiplier.”

Price movements in securities which a Fund owns or intends to purchase probably will not correlate perfectly with movements in the level of a securities index and, therefore, if the Fund uses an option for hedging purposes, it bears the risk of a loss on a securities index option which is not completely offset by movements in the price of such securities. Because securities index options are settled in cash, a call writer cannot determine the amount of its settlement obligations in advance and, unlike call writing on a specific security, cannot provide in advance for, or cover, its potential settlement obligations by acquiring and holding underlying securities. A Fund may, however, cover call options written on a securities index by holding a mix of securities which substantially replicate the movement of the index or by holding a call option on the securities index with an exercise price no higher than the call option sold.

Compared to the purchase or sale of futures contracts, the purchase of call or put options on an index involves less potential risk to a Fund because the maximum amount at risk is the premium paid for the options plus transactions costs. The writing of a put or call option on an index involves risks similar to those risks relating to the purchase or sale of index futures contracts.

Risks involved in the use of options. The successful use of a Fund’s options strategies depends on the ability of the Adviser to forecast correctly interest rate and market movements. For example, if a Fund were to write a call option based on the Adviser’s expectation that the price of the underlying security would fall, but the price were to rise instead, the Fund could be required to sell the security upon exercise at a price below the current market price. Similarly, if a Fund were to write a put option based on the Adviser’s expectation that the price of the underlying security would rise, but the price were to fall instead, the Fund could be required to purchase the security upon exercise at a price higher than the current market price.

When a Fund purchases an option, it runs the risk that it will lose its entire investment in the option in a relatively short period of time, unless the Fund exercises the option or enters into a closing sale transaction before the option’s expiration. If the price of the underlying security does not rise (in the case of a call) or fall (in the case of a put) to an extent sufficient to cover the option premium and transaction costs, a Fund will lose part or all of its investment in the option. This contrasts with an investment by a Fund in the underlying security, since the Fund will not realize a loss if the security’s price does not change.

The effective use of options also depends on a Fund’s ability to terminate option positions at times when the Adviser deems it desirable to do so. There is no assurance that a Fund will be able to effect closing transactions at any particular time or at an acceptable price.

If a secondary market in options were to become unavailable, a Fund could no longer engage in closing transactions. Lack of investor interest might adversely affect the liquidity of the market for particular options or series of options. A market may discontinue trading of a particular option or options generally. In addition, a market could become temporarily unavailable if unusual events — such as volume in excess of trading or clearing capability — were to interrupt its normal operations.

A market may at times find it necessary to impose restrictions on particular types of options transactions, such as opening transactions. For example, if an underlying security ceases to meet qualifications imposed by the market or the Options Clearing Corporation, new series of options on that security will no longer be opened to replace expiring series, and opening transactions in existing series may be prohibited. If an options market were to become unavailable, a Fund as a holder of an option would be able to realize profits or limit losses only by exercising the option, and the Fund, as option writer, would remain obligated under the option until expiration or exercise.

Disruptions in the markets for the securities underlying options purchased or sold by a Fund could result in losses on the options. If trading is interrupted in an underlying security, the trading of options on that security is normally halted as well. As a result, a Fund as purchaser or writer of an option will be unable to close out its positions until options trading resumes, and it may be faced with considerable losses if trading in the security reopens at a substantially different price. In addition, the Options Clearing Corporation or options markets may impose exercise restrictions. If a prohibition on exercise is imposed at the time when trading in the option has also been halted, a Fund as purchaser or writer of an option will be locked into its position until one of the two restrictions has been lifted. If the Options Clearing Corporation were to determine that the available supply of an underlying security appears insufficient to permit delivery by the writers of all outstanding calls in the event of exercise, it may prohibit indefinitely the exercise of put options. A Fund, as holder of such a put option, could lose its entire investment if the prohibition remained in effect until the put option’s expiration.

Foreign-traded options are subject to many of the same risks presented by internationally-traded securities. In addition, because of time differences between the United States and various foreign countries, and because different holidays are observed in different countries, foreign options markets may be open for trading during hours or on days when U.S. markets are closed. As a result, option premiums may not reflect the current prices of the underlying interest in the United States.

Over-the-counter (“OTC”) options purchased by a Fund and assets held to cover OTC options written by the Fund may, under certain circumstances, be considered illiquid securities for purposes of any limitation on the Fund’s ability to invest in illiquid securities.

In addition to the mortgage related securities discussed above, the Funds may invest in asset-backed securities that are not mortgage-related. Asset-backed securities other than mortgage-related securities represent undivided fractional interests in pools of instruments, such as consumer loans, and are typically similar in structure to mortgage-related pass-through securities. Payments of principal and interest are passed through to holders of the securities and are typically supported by some form of credit enhancement, such as a letter of credit, surety bond, limited guarantee by another entity, or by priority to certain of the borrower’s other securities. The degree of credit-enhancement, if any, varies, applying only until exhausted and generally covering only a fraction of the security’s par value.

Each Fund may invest in securities that are purchased in private placements and, accordingly, are subject to restrictions on resale as a matter of contract or under federal securities laws. While such private placements may offer attractive opportunities for investment not otherwise available on the open market, the securities so purchased are often “restricted securities,” i.e., securities which cannot be sold to the public without registration under the Securities Act of 1933 (the “Securities Act”) or the availability of an exemption from registration (such as Rules 144 or 144A), or which are not readily marketable because they are subject to other legal or contractual delays in or restrictions on resale. Generally speaking, restricted securities may be sold only to qualified institutional buyers, or in a privately negotiated transaction to a limited number of purchasers, or in limited quantities after they have been held for a specified period of time and other conditions are met pursuant to an exemption from registration, or in a public offering for which a registration statement is in effect under the Securities Act.

Because there may be relatively few potential purchasers for such investments, especially under adverse market or economic conditions or in the event of adverse changes in the financial condition of the issuer, the Fund could find it more difficult to sell such securities when the Adviser believes it advisable to do so or may be able to sell such securities only at prices lower than if such securities were more widely held. Market quotations for such securities are generally less readily available than for publicly traded securities. The absence of a trading market can make it difficult to ascertain a market value for such securities for purposes of computing the Fund’s net asset value, and the judgment of the Adviser may at times play a greater role in valuing these securities than in the case of publicly traded securities. Disposing of such securities, which may be illiquid investments, can involve time-consuming negotiation and legal expenses, and it may be difficult or impossible for the Fund to sell them promptly at an acceptable price. The Fund may have to bear the extra expense of registering such securities for resale and the risk of substantial delay in effecting such registration.

A Fund may be deemed to be an “underwriter” for purposes of the Securities Act when selling restricted securities to the public, and in such event the Fund may be liable to purchasers of such securities if the registration statement prepared by the issuer, or the prospectus forming a part of it, is materially inaccurate or misleading.

In addition to these risks, Equity REITs may be affected by changes in the value of the underlying property owned by the trusts, while Mortgage REITs may be affected by the quality of any credit extended. Further, Equity and Mortgage REITs are dependent upon management skills and generally may not be diversified. Equity and Mortgage REITs are also subject to heavy cash flow dependency, defaults by borrowers and self-liquidation. In addition, if applicable, Equity and Mortgage REITs could possibly fail to qualify for the favorable tax treatment available to REITs under the Code, or to maintain their exemptions from registration under the 1940 Act. The above factors may also adversely affect a borrower’s or a lessee’s ability to meet its obligations to the REIT. In the event of a default by a borrower or lessee, the REIT may experience delays in enforcing its rights as a mortgagee or lessor and may incur substantial costs associated with protecting investments.

The Funds may enter into repurchase agreements with banks, other financial institutions, such as broker-dealers, and other institutional counterparties. Under a repurchase agreement, a Fund purchases securities from a financial institution that agrees to repurchase the securities at the Fund’s original purchase price plus interest within a specified time. A Fund will limit repurchase transactions to those member banks of the Federal Reserve System, broker-dealers and other financial institutions whose creditworthiness the Adviser considers satisfactory. Should the counterparty to a transaction fail financially, the Fund may encounter delay and incur costs before being able to sell the securities, or may be prevented from realizing on the securities. Further, the amount realized upon the sale of the securities may be less than that necessary to fully compensate the Fund.

Certain Funds may invest in securities of Chinese issuers. Investing in securities of Chinese issuers, including by investing in A Shares, involves certain risks and considerations not typically associated with investing in securities of U.S. issuers, including, among others, (i) more frequent (and potentially widespread) trading suspensions and U.S. or foreign government interventions or restrictions with respect to Chinese issuers, which could preclude the Fund from making certain investments or result in the Fund selling investments at disadvantageous times and which may also cause reduced liquidity and increased price volatility in such investments, (ii) currency revaluations and other currency exchange rate fluctuations or blockage, (iii) the nature and extent of intervention by the

In addition, unexpected political, regulatory and diplomatic events, such as the U.S.-China “trade war” that intensified in 2018, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. The current political climate and the further escalation of a trade war between China and the United States may have an adverse effect on both the U.S. and Chinese economies, as each country has recently imposed tariffs on the other country’s products. Some U.S. politicians have recently sought to limit certain U.S. investors from investing in Chinese companies. In January 2020, the U.S. and China signed a “Phase 1” trade agreement that reduced some U.S. tariffs on Chinese goods while boosting Chinese purchases of American goods. However, this agreement left in place a number of existing tariffs, and it is unclear whether further trade agreements may be reached in the future. Events such as these and their impact on the Funds are difficult to predict and it is unclear whether further tariffs may be imposed or other escalating actions may be taken in the future.

The Funds may contract with a counterparty to pay a stream of cash flows and receive the total return of an index or a security for purposes of attempting to obtain a particular desired return at a lower cost to a Fund than if the Fund had invested directly in an instrument that yielded that desired return. A Fund’s return on a swap will depend on the ability of its counterparty to perform its obligations under the swap. The Adviser will cause a Fund to enter into swap agreements only with counterparties that would be eligible for consideration as repurchase agreement counterparties under the Fund’s repurchase agreement guidelines.

The Funds may enter into interest rate swap transactions with respect to any security they are entitled to hold. Interest rate swaps involve the exchange by a Fund with another party of their respective rights to receive interest, e.g., an exchange of floating rate payments for fixed rate payments. The Funds expect to enter into these transactions primarily to preserve a return or spread on a particular investment or portion of its portfolio or to protect against any increase in the price of securities it anticipates purchasing at a later date. The Funds generally intend to use these transactions as a hedge and not as a speculative investment. For example, a Fund may enter into an interest rate swap in order to protect against declines in the value of fixed income securities held by the Funds. In such an instance, the Fund may agree with a counterparty to pay a fixed rate (multiplied by a notional amount) and the counterparty to pay a floating rate multiplied by the same notional amount. If interest rates rise, resulting in a diminution in the value of a Fund, the Fund would receive payments under the swap that would offset, in whole or in part, such diminution in value; if interest rates fall, the Fund would likely lose money on the swap transaction.

The Funds may invest in Inflation-Protection Securities (“TIPSs”), a type of inflation-indexed Treasury security. TIPSs typically provide for semiannual payments of interest and a payment of principal at maturity. In general, each payment will be adjusted to take into account any inflation or deflation that occurs between the issue date of the security and the payment date based on the Consumer Price Index for All Urban Consumers (“CPI-U”).

The Funds may purchase U.S. Government securities. The types of U.S. Government obligations in which the Funds may at times invest include: (1) U.S. Treasury obligations and (2) obligations issued or guaranteed by U.S. Government agencies and instrumentalities which are supported by any of the following: (a) the full faith and credit of the U.S. Treasury, (b) the right of the issuer to borrow an amount limited to a specific line of credit from the U.S. Treasury, (c) discretionary authority of the U.S. Government agency or instrumentality, or (d) the credit of the instrumentality (examples of agencies and instrumentalities are: Federal Land Banks, Federal Housing Administration, Federal Farm Credit Bank, Farmers Home Administration, Export-Import Bank of the United States, Central Bank for Cooperatives, Federal Intermediate Credit Banks, Federal Home Loan Banks, General Services Administration, Maritime Administration, Tennessee Development Bank, Asian-American Development Bank, International Bank for Reconstruction and Development and Federal National Mortgage Association). No assurance can be given that in the future the U.S. Government will provide financial support to U.S. Government securities it is not obligated to support.

Investing in U.S. registered, dollar-denominated, securities issued by non-U.S. issuers involves some risks and considerations not typically associated with investing in U.S. companies. These include differences in accounting, auditing and financial reporting standards, the possibility of expropriation taxation (which could potentially be confiscatory), adverse changes in investment or exchange control regulations, political instability which could affect U.S. investments in non-U.S. countries, and potential restrictions of the flow of international capital. Non-U.S. companies may be subject to less governmental regulation than U.S. issuers. Moreover, individual non-U.S. economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rate of inflation, capital reinvestment, resource self-sufficiency and balance of payment positions.

A Fund’s investment in common stock of non-U.S. corporations may also be in the form of American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”) and European Depositary Receipts (“EDRs”) (collectively “Depositary Receipts”). Depositary Receipts are receipts, typically issued by a bank or trust company, which evidence ownership of underlying securities issued by a non-U.S. corporation. For ADRs, the depository is typically a U.S. financial institution and the underlying securities are issued by a non-U.S. issuer. For other Depositary Receipts, the depository may be a non-U.S. or a U.S. entity, and the underlying securities may have a non-U.S. or a U.S. issuer. Depositary Receipts will not necessarily be denominated in the same currency as their underlying securities. Generally, ADRs, in registered form, are designed for use in the U.S. securities markets, and EDRs, in bearer form, are designated for use in European securities markets. GDRs are tradable both in the United States and in Europe and are designed for use throughout the world. A Fund may invest in unsponsored Depositary Receipts. The issuers of unsponsored Depositary Receipts are not obligated to disclose material information in the United States, and, therefore, there may be less information available regarding such issuers and there may not be a correlation between such information and the market value of the Depositary Receipts.

The Funds may invest in variable amount master demand notes which are unsecured obligations that are redeemable upon demand and are typically unrated. These instruments are issued pursuant to written agreements between their issuers and holders. The agreements permit the holders to increase (subject to an agreed maximum) and the holders and issuers to decrease the principal amount of the notes, and specify that the rate of interest payable on the principal fluctuates according to an agreed formula. Generally, changes in interest rates will have a smaller effect on the market value of these securities than on the market value of comparable fixed income obligations. Thus, investing in these securities generally allows less opportunity for capital appreciation and depreciation than investing in comparable fixed income securities. There may be no active secondary market with respect to a particular variable rate instrument.

The Funds may invest in variable and floating rate securities. In general, variable rate securities are instruments issued or guaranteed by entities such as (1) U.S. Government, or an agency or instrumentality thereof, (2) corporations, (3) financial institutions, (4) insurance companies or (5) trusts that have a rate of interest subject to adjustment at regular intervals but less frequently than annually. A variable rate security provides for the automatic establishment of a new interest rate on set dates. Interest rates on these securities are ordinarily tied to, widely recognized market rates, which are typically set once a day. These rates may change as often as twice daily. Generally, changes in interest rates will have a smaller effect on the market value of variable and floating rate securities than on the market value of comparable fixed income obligations. Variable rate obligations will be deemed to have a maturity equal to the period remaining until the next readjustment of the interest rate.

To secure an advantageous price or yield, certain Funds may purchase securities on a when-issued, delayed delivery, to-be-announced (“TBA”) or forward commitment basis and may sell securities on a forward commitment or delayed delivery basis. A Fund will enter into when-issued, delayed delivery, TBA or forward commitment transactions for the purpose of acquiring securities and not for the purpose of leverage.

When purchasing a security on a when-issued, delayed delivery, TBA or forward commitment basis, a Fund assumes the rights and risks of ownership of the security, including the risk of price and yield fluctuations, and takes such fluctuations into account when determining its NAV. When such transactions are negotiated, certain terms may be fixed at the time the commitment is made, but delivery and payment for the securities takes place at a later date. In general, a Fund does not pay for the securities until received and does not start earning interest or other income until the contractual settlement date. A Fund may take delivery of the securities or it may sell the securities before the settlement date.

At the time of delivery of the securities, the value may be more or less than the purchase or sale price. If a Fund remains substantially fully invested at a time when when-issued, delayed delivery, TBA or forward commitment purchases are outstanding, the purchases may result in a form of leverage and give rise to increased volatility of the Fund’s NAV. Default by, or bankruptcy of, a counterparty to a when-issued, delayed delivery, TBA or forward commitment transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. Purchases of when-issued, delayed delivery, TBA or forward commitment securities also involve a risk of loss if the seller fails to deliver after the value of the securities has risen.

A TBA transaction involves a commitment to purchase securities sold for a fixed price where the underlying securities are announced at a future date. The seller does not specify the particular securities to be delivered. Instead, a Fund agrees to accept any security that meets specified terms. For example, in a TBA mortgage-backed security transaction, a Fund and the seller would agree upon the issuer, interest rate and terms of the underlying mortgages. The seller would not identify the specific underlying mortgages until it issues the security. For this reason, in a TBA transaction, a Fund commits to purchase securities for which all specific information is not yet known at the time of the trade, particularly the exact face amount in forward commitment mortgage-backed securities transactions. The purchaser in a TBA transaction generally is subject to increased market risk and interest rate risk because the delivered securities may be less favorable than anticipated by the purchaser.

Certain Funds may also enter into a forward commitment to sell securities it owns. The use of forward commitments enables a Fund to hedge against anticipated changes in interest rates and prices. In a forward sale, a Fund does not participate in gains or losses on the security occurring after the commitment date. Forward commitments to sell securities also involve a risk of loss if the seller fails to take delivery after the value of the securities has declined. Forward commitment transactions involve additional risks similar to those associated with investments in options and futures contracts.

Privately-issued stripped securities are not themselves guaranteed by the U.S. Government, but the future payment of principal or interest on U.S. Treasury obligations which they represent is so guaranteed.

A Fund may be required to earmark or otherwise segregate liquid assets in respect of its obligations under derivatives transactions that involve contractual obligations to pay in the future, or a Fund may engage in other measures to “cover” its obligations with respect to such transactions. The amounts that are earmarked or otherwise segregated may be based on the notional value of the derivative or on the daily mark-to-market obligation under the derivatives contract and may be reduced by amounts on deposit with the applicable broker or counterparty to the derivatives transaction. In certain circumstances, a Fund may enter into an offsetting position rather than earmarking or segregating liquid assets. A Fund may modify its asset segregation and coverage policies from time to time. Although earmarking or segregating may in certain cases have the effect of limiting a Fund’s ability to engage in derivatives transactions, the extent of any such limitation will depend on a variety of factors, including the method by which the Fund determines the nature and amount of assets to be earmarked or segregated.

The Emerging Markets Equity Index Fund, the Hedged International Developed Equity Index Fund and International Value Spotlight Fund, and the Target Retirement Funds may in the future determine to become a “feeder” fund that invests all of its assets in another open-end investment company (a “master fund”) that has substantially similar investment strategies as the Fund. This structure is sometimes called a “master/feeder” structure.

The Portfolios in which the Feeder Funds invest each have substantially the same investment restrictions as their corresponding Funds. In reviewing the description of a Feeder Fund’s investment restrictions below, you should assume that the investment restrictions of the corresponding Portfolio are the same in all material respects as those of the Feeder Fund.

The Trust has adopted the following fundamental investment restrictions with respect to the Funds, which may not be changed without the affirmative vote of a “majority of the outstanding voting securities” of a Fund, which is defined in the 1940 Act to mean the affirmative vote of the lesser of (1) more than 50% of the outstanding shares of the Fund and (2) 67% or more of the shares present at a meeting if more than 50% of the outstanding shares are present at the meeting in person or by proxy.

6. A Fund may not purchase any security if, as a result, 25% or more of the Fund’s total assets (taken at current value) would be invested in a particular industry (for purposes of this restriction, investment companies are not considered to constitute a particular industry or group of industries), except as is consistent with applicable law from time to time and as follows: each Fund is permitted to invest without limit in “government securities” (as defined in the 1940 Act) and tax-exempt securities issued by a U.S. territory or possession, a state or local government, or a political subdivision of any of the foregoing. Each Fund may concentrate its investments in securities of issuers in the same industry as may be necessary to approximate the composition of the Fund’s underlying Index.

Fundamental Investment Restrictions (1) through (5), as numbered above limit a Fund’s ability to engage in certain investment practices and purchase securities or other instruments to the extent consistent with applicable law as that law changes from time to time. Applicable law includes the 1940 Act, the rules or regulations thereunder and applicable orders of the SEC as are currently in place. In addition, interpretations and guidance provided by the SEC staff may be taken into account, where deemed appropriate by a Fund, to determine if an investment practice or the purchase of securities or other instruments is permitted by applicable law. As such, the effects of these limitations will change as the statute, rules, regulations or orders (or, if applicable, interpretations) change, and no shareholder vote will be required or sought when such changes permit or require a resulting change in practice.

For the Target Retirement Funds (subject to each Fund’s respective glide path allocations):

The policies set forth below to be followed by State Street and SSGA FM (collectively, the “Service Providers”) for the disclosure of information about the portfolio holdings of the SSGA Funds, State Street Master Funds, and State Street Institutional Investment Trust (each, a “Trust”). These disclosure policies are intended to ensure compliance by the Service Providers and the Trust with applicable regulations of the federal securities laws, including the 1940 Act and the Investment Advisers Act of 1940, as amended. The Board of Trustees must approve all material amendments to the policy.

It is the policy of the Service Providers to protect the confidentiality of client holdings and prevent the selective disclosure of non-public information concerning the Trust.

The Board of Trustees exercises continuing oversight over the disclosure of each Fund’s holdings by (i) overseeing the implementation and enforcement of the portfolio holding disclosure policy, Codes of Ethics and other relevant policies of each Fund and its Service Providers by the Trust’s Chief Compliance Officer (“CCO”), and (ii) considering reports and recommendations by the Trust’s CCO concerning any material compliance matters (as defined in Rule 38a-1 under the 1940 Act). The Board reserves the right to amend the policy at any time without prior notice in its sole discretion.

Publicly Available Information. Any party may disclose portfolio holdings information after the holdings are publicly available.

Disclosure of the complete holdings of each Fund is required to be made quarterly within 60 days of the end of the Fund’s fiscal quarter in the Annual Report and Semi-Annual Report to Fund shareholders and in the monthly holdings report on Form N-PORT, with every third month made available to the public by the SEC 60 days after the end of the Portfolios’ fiscal quarter. You can find SEC filings on the SEC’s website, www.sec.gov. Information about a Fund’s 10 largest holdings generally is posted on the Fund’s website at SSGA.com, within 30 days following the end of each month. Each Fund will also make complete portfolio holdings available generally no later than 60 calendar days after the end of the Funds’ fiscal quarter or subsequent to periodic portfolio holdings disclosure in the Fund’s filings with the SEC or on their website.

Confidentiality Agreement. No non-public disclosure of the Fund’s portfolio holdings will be made to any party unless such party has signed a written Confidentiality Agreement. For purposes of the disclosure policies, any Confidentiality Agreement must be in a form and substance acceptable to, and approved by, the Trust’s officers.

Evaluation Service Providers. There are numerous mutual fund evaluation services (such as Morningstar, Inc. and Broadridge Financial Solutions, Inc., formerly Lipper, Inc.) and due diligence departments of broker-dealers and wirehouses that regularly analyze the portfolio holdings of mutual funds in order to monitor and report on various attributes. These services and departments then distribute the results of their analysis to the public, paid subscribers and/or in-house brokers. In order to facilitate the review of the Trust by these services and departments, the Trust may distribute (or authorize the Service Providers and the Trust’s custodian or fund accountants to distribute) month-end portfolio holdings to such services and departments only if such entity has executed a confidentiality agreement.

The following lists the principal officers for the Trust, as well as their mailing addresses and ages, positions with the Trust and length of time served, and present and principal occupations:

Following is a summary of the experience, attributes and skills which qualify each Trustee to serve on the Boards of Trustees of the Trust and State Street Master Funds.

References to the experience, attributes and skills of Trustees above are pursuant to requirements of the SEC, do not constitute holding out of the Board or any Trustee as having any special expertise or experience, and shall not impose any greater responsibility or liability on any such person or on the Board by reason thereof.

Each of the Governance Committee and the Nominating Committee is composed of all the Independent Trustees. The primary functions of the Governance Committee and the Nominating Committee are to review and evaluate the composition and performance of the Board; make nominations for membership on the Board and committees; review the responsibilities of each committee; and review governance procedures, compensation of Independent Trustees, and independence of outside counsel to the Trustees. The Nominating Committee will consider nominees to the Board recommended by shareholders. Recommendations should be submitted in accordance with the procedures set forth in the Nominating Committee Charter and should be submitted in writing to the Trust, to the

The Trust has adopted proxy voting procedures pursuant to which the Trust delegates the responsibility for voting proxies relating to portfolio securities held by the Funds and Portfolios to the Adviser or Sub-Adviser, as applicable, as part of the Adviser’s and Sub-Adviser’s general management of the Funds and Portfolios, subject to the Board’s continuing oversight. A copy of the Trust’s proxy voting procedures is located in Appendix B, a copy of the Adviser’s and Sub-Adviser’s proxy voting procedures are located in Appendix C.

SSGA FM is responsible for the investment management of the Funds pursuant to the Amended and Restated Investment Advisory Agreement dated November 17, 2015, as amended from time to time (the “Advisory Agreement”), by and between the Adviser and the Trust. The Adviser is a wholly-owned subsidiary of State Street Global Advisors, Inc., which itself is a wholly-owned subsidiary of State Street Corporation, a publicly held financial holding company. State Street is a wholly-owned subsidiary of State Street Corporation.

For the services provided under the Advisory Agreement, each Fund pays the Adviser a fee at an annual rate set forth below of the Fund’s average daily net assets.

Each Feeder Fund currently invests all of its assets in a related Portfolio, which has substantially similar investment strategies as the relevant Fund. The Equity 500 Index II Portfolio, Aggregate Bond Index Portfolio, Global All Cap Equity ex-U.S. Index Portfolio, and the Small/Mid Cap Equity Index Portfolio pay no investment advisory fees to SSGA FM.

For the Aggregate Bond Index Portfolio and the Aggregate Bond Index Fund, the Adviser has contractually agreed to waive up to the portion of the advisory fee and/or expenses attributable to acquired fund fees and expenses, excluding acquired fund fees and expenses derived from the Fund’s holdings in acquired funds for cash management purposes.

For the Hedged International Developed Equity Index Fund and the International Developed Equity Index Fund, the amount each Fund pays under its Investment Advisory Agreement is reduced by the amount of the advisory fee it bears indirectly through its investment in the International Developed Equity Index Portfolio. For the services provided under its Investment Advisory Agreement, the Portfolio pays the Adviser a management fee at the annual rate of 0.11% of the Portfolio’s average daily net assets.

The Adviser and its affiliates may have deposit, loan and other commercial banking relationships with the issuers of obligations that may be purchased on behalf of the Funds, including outstanding loans to such issuers that could be repaid in whole or in part with the proceeds of securities so purchased. Such affiliates deal, trade and invest for their own accounts in such obligations and are among the leading dealers of various types of such obligations. The Adviser has informed the Funds that, in making its investment decisions, it will not obtain or use material non-public information in its possession or in the possession of any of its affiliates. In making investment recommendations for a Fund, the Adviser will not inquire or take into consideration whether an issuer of securities proposed for purchase or sale by the Fund is a customer of the Adviser, its parent or its subsidiaries or affiliates and, in dealing with its customers, the Adviser, its parent, subsidiaries and affiliates will not inquire or take into consideration whether securities of such customers were held by any fund managed by the Adviser or any such affiliate.

The advisory fees paid to SSGA FM for the last three fiscal years are as follows.

As consideration for SSGA FM’s services as administrator with respect to each Fund, SSGA FM receives a fee at the annual rate of 0.05% of the average daily net assets attributable to each class of shares of the Fund. The fees are accrued daily at the rate of 1/365th and payable monthly on the first business day of each month.

State Street receives an annual fee from the Adviser (payable monthly), as consideration for sub-administration services provided to each Fund, except for the Emerging Markets Equity Index Fund and the International Value Spotlight Fund (the “Stand-Alone Funds”). As consideration for custody and fund accounting services, each Fund, except the Stand-Alone Funds, pays State Street an annual fee (payable monthly) based on the average monthly net assets of each Fund. As consideration for sub-administration, custody and fund accounting services provided to the Stand-Alone Funds, the Adviser and the Stand-Alone Funds each pays State Street a portion of the annual fee (payable monthly). Each Fund also pays State Street transaction and service fees for these services and reimburses State Street for out-of-pocket expenses.

The sub-administration (if applicable), custodian and fund accounting fees paid by certain Funds to State Street for the last three fiscal years are set forth in the table below.

DST Asset Manager Solutions, Inc. serves as the Transfer and Dividend Paying Agent. DST Asset Manager Solutions, Inc. is paid for the following annual account services and activities including but not limited to: establishment and maintenance of each shareholder’s account; closing an account; acceptance and processing of trade orders; preparation and transmission of payments for dividends and distributions declared by each Fund; customer service support including receipt of correspondence and responding to shareholder and financial intermediary inquiries; investigation services; tax related support; financial intermediary commission and fee payment processing; and charges related to compliance and regulatory services.

Portfolio fees are allocated to each Fund based on the average NAV of each Fund and are billable on a monthly basis at the rate of 1/12 of the annual fee. DST Asset Manager Solutions, Inc. is reimbursed by each Fund for supplying certain out-of-pocket expenses including confirmation statements, investor statements, banking fees, postage, forms, audio response, telephone, records retention, customized programming/enhancements, reports, transcripts, microfilm, microfiche, and expenses incurred at the specific direction of the Fund. DST Asset Manager Solutions, Inc. principal business address is 2000 Crown Colony Drive, Quincy, MA 02169.

The Fund’s Board has approved each Fund’s participation in a securities lending program. Under the securities lending program, each Fund has retained State Street to serve as the securities lending agent.

collateral, as necessary, from borrowers; (iv) receiving and holding collateral from borrowers, and facilitating the investment and reinvestment of all or substantially all cash collateral in an investment vehicle designated by the Funds; (v) returning collateral to borrowers; (vi) facilitating substitute dividend, interest, and other distribution payments to the Funds from borrowers; (vii) negotiating the terms of each loan of securities, including but not limited to the amount of any loan premium, and monitoring the terms of securities loan agreements with prospective borrowers for consistency with the requirements of the Funds’ Securities Lending Authorization Agreement; (viii) selecting securities, including amounts (percentages), to be loaned; (ix) recordkeeping and accounting servicing; and (x) arranging for return of loaned securities to the Fund in accordance with the terms of the Securities Lending Authorization Agreement.

The Adviser, the Sub-Adviser, SSGA FD and the Trust have each adopted a code of ethics (the Trust’s code being referred to herein as the “Code of Ethics”) under Rule 17j-1 of the 1940 Act. The Code of Ethics, by relying on the codes of the underlying service providers, permits personnel of the Funds’ Adviser, Distributor and officers, subject to the provisions of the relevant code of ethics, to invest in securities, including securities that may be purchased or held by the Adviser or the Trust. Under the relevant code of ethics, all employees or officers who are deemed to be access persons (persons who have interaction with funds or accounts managed by the Adviser or SSGA FD as part of their job function) must pre-clear personal securities transactions. Each code of ethics is designed to ensure that employees conduct their personal securities transactions in a manner that does not create an actual or potential conflict of interest to the business or fiduciary responsibilities of the Trust’s service providers or officers. In addition, the Code of Ethics establishes standards prohibiting the trading in or recommending of securities based on material, nonpublic information or the divulgence of such information to others.

SSGA FD serves as the distributor of the Funds. SSGA FD is an indirect wholly-owned subsidiary of State Street Corporation. SSGA FD’s mailing address is One Iron Street, Boston, MA 02210. The distribution expenses each Fund accrued to SSGA FD for the last three fiscal years are set forth in the table below.

To compensate SSGA FD for the services it provides and for the expenses it bears in connection with the distribution of shares of the Funds, SSGA FD will be entitled to receive any front-end sales load applicable to the sale of shares of the Fund. Each Fund may make payments from the assets attributable to certain classes of its shares to SSGA FD under a distribution plan adopted pursuant to Rule 12b-1 under the 1940 Act (the “Distribution Plan”). The Distribution Plan is a compensation plan that provides for payments at annual rates (based on average daily net assets) described below. Because Rule 12b-1 Fees are paid on an ongoing basis, they will increase the cost of your investment and may cost you more than paying other types of sales loads. The principal business address of SSGA FD is One Iron Street, Boston, MA 02210.

Financial intermediaries are firms that, for compensation, sell shares of mutual funds, including the Funds, and/or provide certain administrative and account maintenance services to mutual fund shareholders. Financial intermediaries may include, among others, brokers, financial planners or advisors, banks, and insurance companies. In some cases, a financial intermediary may hold its clients’ Fund shares in nominee or street name. Shareholder services provided by a financial intermediary may (though they will not necessarily) include, among other things: processing and mailing trade confirmations, periodic statements, prospectuses, annual reports, semi-annual reports, shareholder notices, and other SEC-required communications; capturing and processing tax data; issuing and mailing dividend checks to shareholders who have selected cash distributions; preparing record date shareholder lists for proxy solicitations; collecting and posting distributions to shareholder accounts; and establishing and maintaining systematic withdrawals and automated investment plans and shareholder account registrations. Some portion of SSGA FD’s payments to financial intermediaries will be made out of amounts received by SSGA FD under the Funds’ Distribution Plans. In addition, the Funds may reimburse SSGA FD for payments SSGA FD makes to financial intermediaries that provide recordkeeping, shareholder servicing, sub-transfer agency, administrative and/or account maintenance services (collectively, “servicing”). The amount of the reimbursement for servicing compensation and the manner in which it is calculated are reviewed by the Trustees periodically.

The compensation paid by SSGA FD to a financial intermediary may be paid continually over time, during the period when the intermediary’s clients hold investments in the Funds. The compensation to financial intermediaries may include networking fees and account-based fees. The amount of continuing compensation paid by SSGA FD to different financial intermediaries varies. In the case of most financial intermediaries, compensation for servicing in excess of any amount covered by payments under a Distribution Plan is generally paid at an annual rate of 0.10% – 0.20% of the aggregate average daily NAV of Fund shares held by that financial intermediary’s customers, although in some cases the compensation may be paid at higher annual rates (which may, but will not necessarily, reflect enhanced or additional services provided by the financial intermediary). SSGA FD and its affiliates (including SSGA FM), at their own expense and out of their own assets, may also provide compensation to financial intermediaries in connection with sales of the Funds’ shares or the servicing of shareholders or shareholder accounts by financial intermediaries. Such compensation may include, but is not limited to, ongoing payments, financial assistance to financial intermediaries in connection with conferences, sales, or training programs for their employees, seminars for the public, advertising or sales campaigns, or other financial intermediary-sponsored special events. In some instances, this compensation may be made available only to certain financial intermediaries whose representatives have sold or are expected to sell significant amounts of shares. Financial intermediaries may not use sales of the Funds’ shares to qualify for this compensation to the extent prohibited by the laws or rules of any state or any self-regulatory agency, such as FINRA. The level of payments made to a financial intermediary in any given year will vary and, in the case of most financial intermediaries, will not exceed 0.20% of the value of assets attributable to the financial intermediary invested in shares of funds in the SSGA FM-fund complex. In certain cases, the payments described in the preceding sentence are subject to minimum payment levels.

Because the Funds pay distribution, service and other fees for the sale of their shares and for services provided to shareholders out of the Funds’ assets on an ongoing basis, over time those fees will increase the cost of an investment in a Fund.

Portfolio managers make investment decisions for each account based on the investment objectives and policies and other relevant investment considerations applicable to that portfolio.

SSGA’s culture is complemented and reinforced by a total rewards strategy that is based on a pay for performance philosophy which seeks to offer a competitive pay mix of base salary, benefits, cash incentives and deferred compensation.

Salary is based on a number of factors, including external benchmarking data and market trends, State Street performance, SSGA performance, and individual overall performance. SSGA’s Global Human Resources department regularly participates in compensation surveys in order to provide SSGA with market-based compensation information that helps support individual pay decisions.

Additionally, subject to State Street and SSGA business results, State Street allocates an incentive pool to SSGA to reward its employees. The size of the incentive pool for most business units is based on the firm’s overall profitability and other factors, including performance against risk-related goals. For most SSGA investment teams, SSGA recognizes and rewards performance by linking annual incentive decisions for investment teams to the firm’s or business unit’s profitability and business unit investment performance over a multi-year period.

Incentive pool funding for most active investment teams is driven in part by the post-tax investment performance of fund(s) managed by the team versus the return levels of the benchmark index(es) of the fund(s) on a one-, three- and, in some cases, five-year basis. For most active investment teams, a material portion of incentive compensation for senior staff is deferred over a four-year period into the SSGA Long-Term Incentive (“SSGA LTI”) program. For these teams, The SSGA LTI program indexes the performance of these deferred awards against the post-tax investment performance of fund(s) managed by the team. This is intended to align our investment team’s compensation with client interests, both through annual incentive compensation awards and through the long-term value of deferred awards in the SSGA LTI program.

For the passive equity investment team, incentive pool funding is driven in part by the post-tax 1 and 3-year tracking error of the funds managed by the team against the benchmark indexes of the funds.

The discretionary allocation of the incentive pool to the business units within SSGA is influenced by market-based compensation data, as well as the overall performance of each business unit. Individual compensation decisions are made by the employee’s manager, in conjunction with the senior management of the employee’s business unit. These decisions are based on the overall performance of the employee and, as mentioned above, on the performance of the firm and business unit. Depending on the job level, a portion of the annual incentive may be awarded in deferred compensation, which may include cash and/or Deferred Stock Awards (State Street stock), which typically vest over a four-year period. This helps to retain staff and further aligns SSGA employees’ interests with SSGA clients’ and shareholders’ long-term interests.

Each Feeder Fund invests all, and the Hedged International Developed Equity Index Fund invests substantially all, of its investable assets in a corresponding Portfolio and therefore does not directly incur transactional costs for purchases and sales of portfolio investments (except in the case of Hedged International Developed Equity Index Fund’s currency hedging and related positions). The Funds generally purchase and redeem shares of the corresponding Portfolio each day depending on the number of shares of such Fund purchased or redeemed by investors on that day. Shares of the Portfolios are available for purchase by the Funds at their NAV without any sales charges, transaction fees, or brokerage commissions being charged.

(i) The nature and characteristics of the order or transaction. For example, size of order, market impact of order, limits, or other instructions relating to the order;

(iii) The characteristics of the execution venues to which that order can be directed, if relevant. For example, availability and capabilities of electronic trading systems;

The process by which trading counterparties are selected to effect transactions is designed to exclude consideration of the sales efforts conducted by broker-dealers in relation to the Funds.

The brokerage commissions paid by the Funds for the last three fiscal years are shown below:

Securities of “Regular Broker-Dealer.” Each Trust is required to identify any securities of its “regular brokers and dealers” (as such term is defined in the 1940 Act) which it may hold at the close of its most recent fiscal year. “Regular brokers or dealers” of the Trust are the ten brokers or dealers that, during the most recent fiscal year: (i) received the greatest dollar amounts of brokerage commissions from the Trust’s portfolio transactions; (ii) engaged as principal in the largest dollar amounts of portfolio transactions of the Trust; or (iii) sold the largest dollar amounts of the Trust’s shares.

The Declaration of Trust of the Trust provides that the Trust may redeem shares of a Fund at the redemption price that would apply if the share redemption were initiated by a shareholder. It is the policy of the Trust that, except upon such conditions as may from time to time be set forth in the then current prospectus of the Trust or to facilitate the Trust’s or a Fund’s compliance with applicable law or regulation, the Trust would not initiate a redemption of shares unless it were to determine that failing to do so may have a substantial adverse consequence for a Fund or the Trust.

The Trust’s Declaration of Trust provides that a Trustee who is not an “interested person” (as defined in the 1940 Act) of the Trust will be deemed independent and disinterested with respect to any demand made in connection with a derivative action or proceeding. It is the policy of the Trust that it will not assert that provision to preclude a shareholder from claiming that a trustee is not independent or disinterested with respect to any demand made in connection with a derivative action or proceeding; provided, however, that the foregoing policy will not prevent the Trust from asserting applicable law (including Section 2B of Chapter 182 of the Massachusetts General Laws) to preclude a shareholder from claiming that a trustee is not independent or disinterested with respect to any demand made in connection with a derivative action or proceeding.

The Trust will not deviate from the foregoing policies in a manner that adversely affects the rights of shareholders of a Fund without the approval of “a vote of a majority of the outstanding voting securities” (as defined in the 1940 Act) of such Fund.

Each investor is entitled to a vote in proportion to the number of Fund shares it owns. Shares do not have cumulative voting rights in the election of Trustees, and investors holding more than 50% of the aggregate outstanding shares in the Trust may elect all of the Trustees if they choose to do so. The Trust is not required and has no current intention to hold annual meetings of investors but the Trust will hold special meetings of shareholders when in the judgment of the Trustees it is necessary or desirable to submit matters for a shareholder vote.

Multiple-class funds do not have a single share price. Rather, each class has a share price, called its NAV. The price per share for each class of each Fund is determined each business day (unless otherwise noted) at the close of the New York Stock Exchange (“NYSE”) (ordinarily 4:00 p.m. Eastern time).

The Funds’ securities will be valued pursuant to guidelines established by the Board of Trustees.

Each Fund has elected to be treated as a RIC under Subchapter M of the Code and intends each year to qualify and be eligible to be treated as such. In order to qualify for the special tax treatment accorded RICs and their shareholders, each Fund must, among other things, (a) derive at least 90% of its gross income for each taxable year from (i) dividends, interest, payments with respect to certain securities loans, gains from the sale of securities or foreign currencies, or other income (including but not limited to gains from options, futures or forward contracts) derived with respect to its business of investing in such stock, securities or currencies and (ii) net income derived from interests in “qualified publicly traded partnerships” (as defined below); (b) diversify its holdings so that, at the end of each quarter of the Fund’s taxable year, (i) at least 50% of the value of the Fund’s total assets consists of cash and cash items, U.S. Government securities, securities of other RICs, and other securities limited in respect of any one issuer to a value not greater than 5% of the value of the Fund’s total assets and no more than 10% of the outstanding voting securities of such issuer, and (ii) no more than 25% of its assets are invested, including through corporations in which the Fund owns a 20% or more voting stock interest, (x) in the securities (other than those of the U.S. Government or other RICs) of any one issuer or of two or more issuers which the Fund controls and which are engaged in the same, similar or related trades and businesses, or (y) in the securities of one or more qualified publicly traded partnerships (as defined below); and (c) distribute with respect to each taxable year at least 90% of the sum of its investment company taxable income (as that term is defined in the Code without regard to the deduction for dividends paid — generally taxable ordinary income and the excess, if any, of net short-term capital gains over net long-term capital losses) and net tax-exempt income, for such year.

For purposes of the diversification test in (b) above, the term “outstanding voting securities of such issuer” will include the equity securities of a qualified publicly traded partnership. Also, for purposes of the diversification test in (b) above, the identification of the issuer (or, in some cases, issuers) of a particular investment can depend on the terms and conditions of that investment. In some cases, identification of the issuer (or issuers) is uncertain under current law, and an adverse determination or future guidance by the Internal Revenue Service (“IRS”) with respect to issuer identification for a particular type of investment may adversely affect a Fund’s ability to meet the diversification test in (b) above.

amount equal to the difference between the amount of undistributed capital gains included in the shareholder’s gross income under clause (a) of the preceding sentence and the tax deemed paid by the shareholder under clause (b) of the preceding sentence. The Funds are not required to, and there can be no assurance a Fund will, make this designation if it retains all or a portion of its net capital gain in a taxable year.

Capital losses in excess of capital gains (“net capital losses”) are not permitted to be deducted against a Fund’s net investment income. Instead, potentially subject to certain limitations, a Fund may carry net capital losses from any taxable year forward to subsequent taxable years to offset capital gains, if any, realized during such subsequent taxable years. Distributions from capital gains are generally made after applying any available capital loss carryforwards. Capital loss carryforwards are reduced to the extent they offset current-year net realized capital gains, whether the Fund retains or distributes such gains. A Fund may carry net capital losses forward to one or more subsequent taxable years without expiration; any such carryforward losses will retain their character as short-term or long-term. The Fund must apply such carryforwards first against gains of the same character. See a Fund’s most recent annual shareholder report for the Fund’s available capital loss carryovers as of the end of its most recently ended fiscal year.

For U.S. federal income tax purposes, distributions of investment income are generally taxable to shareholders as ordinary income. Taxes on distributions of capital gains are determined by how long a Fund owned (or is deemed to have owned) the investments that generated them, rather than how long a shareholder has owned his or her Fund shares. In general, a Fund will recognize long-term capital gain or loss on the disposition of assets the Fund has owned (or is deemed to have owned) for more than one year, and short-term capital gain or loss on the disposition of investments the Fund has owned (or is deemed to have owned) for one year or less. Distributions of net-capital gain (that is, the excess of net long-term capital gain over net short-term capital loss) that are properly reported by a Fund as capital gain dividends (“Capital Gain Dividends”) generally will be taxable to a shareholder receiving such distributions as long-term capital gains includible in net capital gain and taxed to individuals at reduced rates relative to ordinary income. Distributions from capital gains are generally made after applying any available capital loss carryforwards. The IRS and the Department of the Treasury have issued regulations that impose special rules in respect of Capital Gain Dividends received through partnership interests constituting “applicable partnership interests” under Section 1061 of the Code. Distributions of net short-term capital gain (as reduced by any net long-term capital loss for the taxable year) will be taxable to shareholders as ordinary income. Distributions of investment income properly reported by a Fund and, in the case of a Fund investing in a Portfolio treated as a RIC, the Portfolio, as derived from “qualified dividend income” will be taxed in the hands of individuals at the rates applicable to net capital gain, provided holding period and other requirements are met at each of the shareholder, the Portfolio and, in the case of a Fund investing in a Portfolio treated as a RIC, the Fund level. The Aggregate Bond Index Fund does not expect its distributions to be derived from qualified dividend income.

Distributions with respect to a Fund’s shares are generally subject to U.S. federal income tax as described herein to the extent they do not exceed the Fund’s realized income and gains, even though such distributions may economically represent a return of a particular shareholder’s investment. Such distributions are likely to occur in respect of shares purchased at a time when a Fund’s NAV includes either unrealized gains, or realized but undistributed income or gains that were therefore included in the price the shareholder paid. Such distributions may reduce the fair market value of the Fund’s shares below the shareholder’s cost basis in those shares. As described above, a Fund is required to distribute realized income and gains regardless of whether the Fund’s NAV also reflects unrealized losses.

In order for some portion of the dividends received by a Fund shareholder to be “qualified dividend income,” the Fund or corresponding Portfolio must meet holding period and other requirements with respect to the dividend-paying stocks held by the Fund or Portfolio, the shareholder must meet holding period and other requirements with respect to the Fund’s shares, and in the case of a Fund investing in a Portfolio treated as a RIC, the Fund must meet holding period and other requirements with respect to its shares in the Portfolio. In general, a dividend will not be treated as qualified dividend income (at any of the Portfolio, Fund or shareholder level, as applicable) (a) if the dividend is received with respect to any share of stock held for fewer than 61 days during the 121-day period beginning on the date which is 60 days before the date on which such share becomes ex-dividend with respect to such dividend (or, in the case of certain preferred stock, 91 days during the 181-day period beginning 90 days before such date), (b) to the extent that the recipient is under an obligation (whether pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property, (c) if the recipient elects to have the dividend income treated as investment income for purposes of the limitation on deductibility of investment interest, or (d) if the dividend is received from a foreign corporation that is (i) not eligible for the benefits of a comprehensive income tax treaty with the United States (with the exception of dividends paid on stock of such a foreign corporation readily tradable on an established securities market in the United States) or (ii) treated as a passive foreign investment company.

In general, distributions of investment income properly reported by a Fund as derived from qualified dividend income will be treated as qualified dividend income in the hands of a shareholder taxed as an individual, provided the shareholder meets the holding period and other requirements described above with respect to the Fund’s shares. If the aggregate qualified dividends (a) received by a Fund (including from a Portfolio that is treated as a RIC) or (b) allocated to a Fund by a Portfolio that is treated as a partnership, during any taxable year are 95% or more of the Fund’s gross income (excluding net long-term capital gain over net short-term capital loss), then 100% of the Fund’s dividends (other than dividends properly reported as Capital Gain Dividends) will be eligible to be treated as qualified dividend income.

In general, dividends of net investment income received by corporate shareholders of a Fund will qualify for the dividends-received deduction generally available to corporations to the extent of the amount of eligible dividends (a) received by a Fund from domestic corporations (including a corresponding Portfolio that is treated as a RIC) or (b) allocated to a Fund by a corresponding Portfolio that is treated as a partnership for the taxable year. A dividend will not be treated as a dividend eligible for the dividends-received deduction (at any of the Portfolio, Fund or shareholder level, as applicable) (a) if it has been received with respect to any share of stock that the Fund or Portfolio has held for less than 46 days (91 days in the case of certain preferred stock) during the 91-day period beginning on the date which is 45 days before the date on which such share becomes ex-dividend with respect to such dividend (during the 181-day period beginning 90 days before such date in the case of certain preferred stock) or (b) to the extent that the Fund or Portfolio is under an obligation (pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property. Moreover, a Fund that invests in a corresponding Portfolio that is treated as a RIC must meet similar requirements with respect to its shares of the corresponding Portfolio. Finally, the dividends-received deduction may otherwise be disallowed or reduced (x) if the corporate shareholder fails to satisfy the foregoing requirements with respect to its shares of the Fund or (y) by application of various provisions of the Code (for instance, the dividends-received deduction is reduced in the case of a dividend received on debt-financed portfolio stock (generally, stock acquired with borrowed funds)). The Aggregate Bond Index Fund does not expect Fund distributions to be eligible for the dividends-received deduction.

If a Fund holds, directly or indirectly, one or more “tax credit bonds” issued on or before December 31, 2017, on one or more applicable dates during a taxable year, the Fund may elect to permit its shareholders to claim a tax credit on their income tax returns equal to each shareholder’s proportionate share of tax credits from the bond otherwise allowed to the Fund. In such a case, a shareholder will be deemed to receive a distribution of money with respect to its Fund shares equal to the shareholder’s proportionate share of the amount of such credits and be allowed a credit against the shareholder’s U.S. federal income tax liability equal to the amount of such deemed distribution. A shareholder’s ability to claim a tax credit associated with one or more tax credit bonds may be subject to certain limitations imposed by the Code, and the amount of the tax credits may not exceed the amount reported by the Fund in a written notice to shareholders. Even if a Fund is eligible to pass through tax credits to shareholders, the Fund may choose not to do so.

As required by federal law, detailed federal tax information with respect to each calendar year will be furnished to each shareholder early in the succeeding year.

Tax Considerations Applicable to Funds Investing in Portfolios Treated as Partnerships

The International Developed Equity Index Fund and the Hedged International Developed Equity Index Fund invest substantially all of their investable assets in a corresponding Portfolio that is treated as a partnership for U.S. federal income tax purposes. The nature and character of each such Fund’s income, gains, losses and deductions will generally be determined at the Portfolio level and each such Fund will be allocated its share of Portfolio income and gains. As applicable, references to income, gains, losses and deductions of a Fund will be to income, gains and losses recognized and deductions accruing at the Portfolio level and allocated to or otherwise taken into account by the Fund, and references to assets of a Fund will be to the Fund’s allocable share of the assets of the corresponding Portfolio.

In addition, in certain circumstances, the “wash sale” rules under Section 1091 of the Code may apply to the Funds’ sales of the corresponding Portfolio interests that have generated losses. A wash sale occurs if equity interests of an issuer are sold by a Fund at a loss and the Fund acquires additional interests of that same issuer 30 days before or after the date of the sale. The wash-sale rules could defer losses in a Fund’s hands on corresponding interests in a Portfolio (to the extent such sales are wash sales) for extended (and, in certain cases, potentially indefinite) periods of time.

Tax Considerations Applicable to Funds Investing in Portfolios and Underlying Funds Treated as RICs

treated as a RIC. Whether each such Fund meets the asset diversification test described above will depend on whether the corresponding Portfolio meets each of the income, asset diversification and distribution tests. If a Portfolio were to fail to meet any such test and were ineligible to or otherwise were not to cure such failure, the corresponding Fund would as a result itself fail to meet the asset diversification test and might be ineligible or unable to or might otherwise not cure such failure.

Each Target Retirement Fund seeks to achieve its investment objectives by investing substantially all of its investable assets in one or more Underlying Funds and each such Underlying Fund intends to elect to be treated and to qualify and be eligible each year to be treated as a RIC. Whether a Target Retirement Fund meets the asset diversification test described above will thus depend in part on whether the Underlying Funds in which it invests meet each of the income, asset diversification, and distribution tests. If an Underlying were to fail to meet any such test and were ineligible to or otherwise were not to cure such failure, the corresponding Fund might as a result itself fail to meet the asset diversification test and might be ineligible or unable to or might otherwise not cure such failure.

Each such Fund’s distributable income and gains will normally consist substantially of distributions from the corresponding Portfolio or the Underlying Funds in which it invests. To the extent that a Portfolio or Underlying Fund realizes net losses on its investments for a given taxable year, the corresponding Fund will not be able to benefit from those losses until and only to the extent that (i) the Portfolio or Underlying Fund realizes gains that it can reduce by those losses, or (ii) the Fund recognizes its share of those losses when it disposes of shares of the Portfolio or Underlying Fund in a transaction qualifying for sale or exchange treatment. Moreover, even when a Fund does make such a disposition, any loss will be recognized as a capital loss, a portion of which may be a long-term capital loss. A Fund will not be able to offset any capital losses from its dispositions of shares of the corresponding Portfolio or Underlying Funds against its ordinary income (including distributions of any net short-term capital gains realized by a Portfolio or Underlying Fund), and the Fund’s long-term capital losses first offset its long-term capital gains, increasing the likelihood that the Fund’s short-term capital gains are distributed to shareholders as ordinary income.

In addition, in certain circumstances, the “wash sale” rules under Section 1091 of the Code may apply to these Funds’ sales of the corresponding Portfolio or Underlying Fund shares that have generated losses. A wash sale occurs if shares of an issuer are sold by a Fund at a loss and the Fund acquires additional shares of that same issuer 30 days before or after the date of the sale. The wash-sale rules could defer losses in these Funds’ hands on corresponding Portfolio or Underlying Fund shares (to the extent such sales are wash sales) for extended (and, in certain cases, potentially indefinite) periods of time.

The Code’s wash sale rule may also apply to certain redemptions and exchanges by non-U.S. shareholders. See “Non-U.S. Shareholders” below.

Investments in Other RICs. If a Fund receives dividends from a Portfolio treated as a RIC, or an Underlying Fund, or another underlying RIC (each, an “underlying RIC”) or a Portfolio or an Underlying Fund receives dividends from an underlying RIC, and the underlying RIC reports such dividends as qualified dividend income, then the Fund, the Portfolio or the Underlying Fund, as applicable, is permitted, in turn, to report a portion of such dividends as “qualified dividend income” when it distributes such portion to its shareholders, provided holding period and other requirements are met.

If a Fund, a Portfolio or Underlying Fund receives dividends from an underlying RIC, and the underlying RIC reports such dividends as eligible for the dividends-received deduction, then the Fund, the Portfolio or the Underlying Fund, as applicable, is permitted, in turn, to report a portion of such dividends as eligible for the dividends-received deduction as well when it distributes such portion to its shareholders, provided holding period and other requirements are met.

Securities Purchased at a Premium. Very generally, where a Fund purchases a bond at a price that exceeds the redemption price at maturity – that is, at a premium — the premium is amortizable over the remaining term of the bond. In the case of a taxable bond, if a Fund makes an election applicable to all such bonds it purchases, which election is irrevocable without consent of the IRS, the Fund reduces the current taxable income from the bond by the amortized premium and reduces its tax basis in the bond by the amount of such offset; upon the disposition or maturity of such bonds acquired on or after January 4, 2013, the Fund is permitted to deduct any remaining premium allocable to a prior period.

At-risk or Defaulted Securities. Investments in debt obligations that are at risk of or in default present special tax issues for the Funds. Tax rules are not entirely clear about issues such as when a Fund may cease to accrue interest, OID or market discount; whether, when or to what extent the Fund should recognize market discount on a debt obligation; when and to what extent a Fund may take deductions for bad debts or worthless securities; and how a Fund should allocate payments received on obligations in default between principal and income. These and other related issues will be addressed by a Fund when, as and if it invests in such securities, in order to seek to ensure that it distributes sufficient income to preserve its status as a RIC and does not become subject to U.S. federal income or excise tax.

Certain Investments in REITs. Any investment by a Fund in equity securities of real estate investment trusts qualifying as such under Subchapter M of the Code (“REITs”) may result in the Fund’s receipt of cash in excess of the REIT’s earnings; if the Fund distributes these amounts, these distributions could constitute a return of capital to Fund shareholders for U.S. federal income tax purposes. Dividends received by a Fund from a REIT will not qualify for the corporate dividends-received deduction and generally will not constitute qualified dividend income.

Passive Foreign Investment Companies. Equity investments by a Fund in certain “passive foreign investment companies” (“PFICs”) could potentially subject the Fund to a U.S. federal income tax (including interest charges) on distributions received from the company or on proceeds received from the disposition of shares in the company. This tax cannot be eliminated by making distributions to Fund shareholders. However, a Fund may elect to avoid the imposition of that tax. For example, a Fund may elect to treat a PFIC as a “qualified electing fund” (i.e., make a “QEF election”), in which case the Fund will be required to include its share of the PFIC ’s income and net capital gains annually, regardless of whether it receives any distribution from the PFIC. A Fund also may make an election to mark the gains (and to a limited extent losses) in such holdings “to the market” as though it had sold (and, solely for purposes of this mark-to-market election, repurchased) its holdings in those PFICs on the last day of the Fund’s taxable year. Such gains and losses are treated as ordinary income and loss. The QEF and mark-to-market elections may accelerate the recognition of income (without the receipt of cash) and increase the amount required to be distributed by the Fund to avoid taxation. Either of these elections therefore may require a Fund to liquidate other investments (including when it is not advantageous to do so) to meet its distribution requirement, which also may accelerate the recognition of gain and affect the Fund’s total return. Dividends paid by PFICs will not be eligible to be treated as “qualified dividend income.”

Because it is not always possible to identify a foreign corporation as a PFIC, a Fund may incur the tax and interest charges described above in some instances.

Commodity-Linked Instruments. A Fund’s direct or indirect investments in commodities and commodity-linked instruments can be limited by the Fund’s intention to qualify as a RIC, and can bear on the Fund’s ability to so qualify. Income and gains from commodities and certain commodity-linked instruments does not constitute qualifying income to a RIC for purposes of the 90% gross income test described above. The tax treatment of some other commodity-linked instruments in which a Fund might invest is not certain, in particular with respect to whether income or gains from such instruments constitute qualifying income to a RIC. If a Fund were to treat income or gain from a particular instrument as qualifying income and the income or gain were later determined not to constitute qualifying income and, together with any other nonqualifying income, caused the Fund’s nonqualifying income to exceed 10% of its gross income in any taxable year, the Fund would fail to qualify as a RIC unless it is eligible to and does pay a tax at the Fund level.

A Fund’s income, proceeds and gains from sources within foreign countries may be subject to non-U.S. withholding or other taxes, which will reduce the yield on those investments. Tax conventions between certain countries and the United States may reduce or eliminate such taxes. If, at the close of a Fund’s taxable year, more than 50% of the assets of the Fund consists of the securities of foreign corporations, the Fund may elect to permit shareholders to claim a credit or deduction on their income tax returns for their pro rata portions of qualified taxes paid by a Fund to foreign countries in respect of foreign securities that the Fund has held for at least the minimum period specified in the Code. In such a case, shareholders will include in gross income from foreign sources their pro rata shares of such taxes paid by such Fund. A shareholder’s ability to claim an offsetting foreign tax credit or deduction in respect of foreign taxes paid by a Fund is subject to certain limitations imposed by the Code, which may result in the shareholder’s not receiving a full credit or deduction (if any) for the amount of such taxes. Shareholders who do not itemize on their U.S. federal income tax returns may claim a credit (but not a deduction) for such foreign taxes. Even if a Fund were eligible to make such an election for a given year, it may determine not to do so.

If a Fund does not qualify for or does not make such election, shareholders will not be entitled to claim a credit or deduction with respect to foreign taxes paid by the Fund; in that case the foreign tax will nonetheless reduce the Fund’s taxable income. Shareholders that are not subject to U.S. federal income tax, and those who invest in a Fund through tax-advantaged accounts (including those who invest through individual retirement accounts or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit or deduction passed through by the Fund, if any. Under certain circumstances, if the Fund receives a refund of foreign taxes paid in respect of a prior year, the value of Fund Shares could be affected or any foreign tax credits or deductions passed through to shareholders in respect of the Fund’s foreign taxes for the current year could be reduced.

If at the close of each quarter of its taxable year, at least 50% of the total assets of a Fund consists of interests in other RICs (such as a Portfolio or Underlying Fund treated as a RIC), such Fund will be a “qualified fund of funds.” In that case, the Fund is permitted to elect to pass through to its shareholders foreign income and other similar taxes paid by the Fund in respect of foreign securities held directly by the Fund or by the underlying RIC in which it invests that itself elected to pass such taxes through to shareholders. However, even if a Fund qualifies to make such election for any year, it may determine not to do so. Shareholders that are not subject to U.S. federal income tax, and those who invest in a Fund through tax-advantaged accounts (including those who invest through individual retirement accounts or other tax-advantaged retirement plans), generally will receive no benefit from any tax credit or deduction passed through by the Fund.

A Fund generally is required to withhold and remit to the U.S. Treasury a percentage of the taxable distributions and redemption proceeds paid to any individual shareholder who fails to properly furnish the Fund with a correct taxpayer identification number (“TIN”), who has under- reported dividend or interest income, or who fails to certify to the Fund that he or she is not subject to such withholding.

Under IRS guidance issued in October 2006, a CRT will not recognize UBTI as a result of investing in a RIC that recognizes “excess inclusion income.” Rather, if at any time during any taxable year a CRT (or one of certain other tax-exempt shareholders, such as the United States, a state or political subdivision, or an agency or instrumentality thereof, and certain energy cooperatives) is a record holder of a share in a RIC that recognizes “excess inclusion income,” then the RIC will be subject to a tax on that portion of its “excess inclusion income” for the taxable year that is allocable to such shareholders at the highest federal corporate income tax rate. The extent to which this IRS guidance remains applicable in light of the December 2006 legislation is unclear. To the extent permitted under the 1940 Act, each Fund may elect to specially allocate any such tax to the applicable CRT, or other shareholder, and thus reduce such shareholder’s distributions for the year by the amount of the tax that relates to such shareholder’s interest in a Fund. CRTs are urged to consult their tax advisors concerning the consequences of investing in each Fund.

Redemptions and exchanges of each Fund’s shares are taxable events and, accordingly, shareholders may realize gain or loss on these transactions. In general, any gain or loss realized upon a taxable disposition of shares will be treated as long-term capital gain or loss if the shares have been held for more than 12 months. Otherwise, the gain or loss on the taxable disposition of Fund shares will be treated as short-term capital gain or loss. However, any loss realized upon a taxable disposition of Fund shares held by a shareholder for six months or less will be treated as long-term, rather than short-term, to the extent of any Capital Gain Dividends received (or deemed received) by the shareholder with respect to the shares. Further, all or a portion of any loss realized upon a taxable disposition of Fund shares generally will be disallowed under the Code’s “wash sale” rule if other substantially identical shares are purchased, including by means of dividend reinvestment, within 30 days before or after the disposition. In such a case, the basis of the newly purchased shares will be adjusted to reflect the disallowed loss.

Foreign shareholders should contact their intermediaries regarding the application of withholding rules to their accounts.

Special rules would apply if a Fund were a qualified investment entity (“QIE”) because it is either a “U.S. real property holding corporation” (“USRPHC”) or would be a USRPHC but for the operation of certain exceptions to the definition thereof. Very generally, a USRPHC is a domestic corporation that holds USRPIs the fair market value of which equals or exceeds 50% of the sum of the fair market values of the corporation’s USRPIs, interests in real property located outside the United States, and other trade or business assets. USRPIs are generally defined as any interest in U.S. real property and any interest (other than solely as a creditor) in a USRPHC or, very generally, an entity that has been a USRPHC in the last five years. A Fund that holds, directly or indirectly, significant interests in REITs may be a USRPHC. Interests in domestically controlled QIEs, including REITs and RICs that are QIEs, not-greater-than-10% interests in publicly traded classes of stock in REITs and not-greater-than-5% interests in publicly traded classes of stock in RICs generally are not USRPIs, but these exceptions do not apply for purposes of determining whether a Fund is a QIE. If an interest in a Fund were a USRPI, the Fund would be required to withhold U.S. tax on the proceeds of a share redemption by a greater-than-5% foreign shareholder, in which case such foreign shareholder generally would also be required to file U.S. tax returns and pay any additional taxes due in connection with the redemption.

Foreign shareholders should consult their tax advisers and, if holding shares through intermediaries, their intermediaries, concerning the application of these rules to their investment in a Fund.

A foreign shareholder may be subject to state and local tax and to the U.S. federal estate tax in addition to the U.S. federal income tax on income referred to above.

SSGA FD serves as the Funds’ distributor pursuant to the Distribution Agreement by and between SSGA FD and the Trust. Pursuant to the Distribution Agreement, the Funds pay SSGA FD fees under the Rule 12b-1 Plan in effect for the Funds. For a description of the fees paid to SSGA FD under the Rule 12b-1 Plan, see “Shareholder Servicing and Distribution Plans,” above. SSGA FD is not obligated to sell any specific number of shares and will sell shares of a Fund on a continuous basis only against orders to purchase shares. The principal business address of SSGA FD is One Iron Street, Boston, MA 02210.