BlackRock Summit Cash Reserves Fund

Fund Overview

Key Facts About BlackRock Summit Cash Reserves Fund

Investment Objective

The investment objective of BlackRock Summit Cash Reserves Fund (the “Fund”) of BlackRock Financial Institutions Series Trust (the “Trust”) is to seek current income, preservation of capital and liquidity available from investing in a diversified portfolio of short-term money market securities.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock Advisors, LLC (“BlackRock”) and its affiliates) (each, a “Financial Intermediary”), which are not reflected in the table and example below. More information about these fees and expenses is available from your Financial Intermediary and in the “Details About the Share Classes” and the “Intermediary-Defined Sales Charge Waiver Policies” sections on pages 19 and A-1, respectively, of the Fund’s prospectus and in the “Purchase of Shares” section on page II-30 of Part II of the Fund’s Statement of Additional Information.


Shareholder Fees (fees paid directly from your investment)	Investor A Shares	Investor C Shares	Institutional Shares
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 offering price or redemption proceeds, whichever is lower)	None¹	1.00 %²	None


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)	Investor A Shares	Investor C Shares	Institutional Shares
Management Fee	0.50%	0.50%	0.50%
Distribution (12b-1) Fees	None	0.75%	None
Other Expenses	0.09%	0.10%	0.09%
Total Annual Fund Operating Expenses	0.59%	1.35%	0.59%
Fee Waivers and/or Expense Reimbursements³	(0.17%)	(0.18%)	(0.17%)
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements³	0.42%	1.17%	0.42%


¹	There is no contingent deferred sales charge (“CDSC”) on Investor A Shares purchased directly. However, a CDSC of up to 1.00% may apply to certain redemptions of the Fund’s Investor A Shares purchased in an exchange transaction for Investor A Shares of a fund advised by BlackRock or its affiliates where no initial sales charge was paid at the time of purchase of such fund (each, an “Investor A Load-Waived BlackRock Fund”) as part of an investment of $1,000,000 (lesser amounts may apply depending on the Investor A Load-Waived BlackRock Fund) or more. The Investor A Shares CDSC is only charged upon redemptions of Investor A Shares within 18 months after you originally acquired such Investor A Shares of the Investor A Load-Waived BlackRock Fund (a shorter holding period may apply depending on the Investor A Load-Waived BlackRock Fund), unless you qualify for a waiver. There is no CDSC charged on redemptions if you have owned your Investor A Shares for more than 18 months (or for a shorter holding period, as applicable) as measured from your original purchase of Investor A Shares that you exchanged into Investor A Shares of the Fund or if you purchase Investor A Shares of the Fund not through an exchange.
²	Since all Investor C Shares must be purchased in an exchange transaction for Investor C Shares of a non-money market fund advised by BlackRock or its affiliates (each a “Non-Money Market BlackRock Fund”), a CDSC of 1.00% may apply to certain redemptions of the Fund’s Investor C Shares. The Investor C Shares CDSC is only charged upon redemptions of Investor C Shares within one year after you originally acquired the Investor C Shares of the Non-Money Market BlackRock Fund, unless you qualify for a waiver. There is no CDSC charged on redemptions if you have owned your Investor C Shares for more than one year (as measured from your original purchase of Investor C Shares that you exchanged into Investor C Shares of the Fund).
³	As described in the “Management of the Fund” section of the Fund’s prospectus beginning on page 31, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) as a percentage of average daily net assets to 0.42% for Investor A Shares and Institutional Shares and 1.17% for Investor C Shares through

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June 30, 2025. The agreement may be terminated upon 90 days’ notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

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 redeem all of your 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. 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
Investor A Shares¹	$43	$172	$312	$722
Investor C Shares²	$219	$410	$722	$1,399
Institutional Shares	$43	$172	$312	$722

¹	These expense figures do not reflect the imposition of the CDSC which may be deducted upon the redemption of Investor A Shares of the Fund received in an exchange transaction for Investor A Shares of an Investor A Load-Waived BlackRock Fund as described in the applicable prospectuses. No CDSC is deducted upon the redemption of Investor A Shares of the Fund that are not acquired by exchange.
²	Reflects assessment of applicable CDSC assuming Investor C Shares were acquired by exchange from a Non-Money Market BlackRock Fund immediately after purchase of shares from such other fund.

You would pay the following expenses if you did not redeem your shares:


	1 Year	3 Years	5 Years	10 Years
Investor C Shares	$119	$410	$722	$1,399

Principal Investment Strategies of the Fund

The Fund invests at least 99.5% of its total assets in cash, U.S. Treasury bills, notes and other obligations issued or guaranteed as to principal and interest by the U.S. Government, its agencies or instrumentalities, and repurchase agreements secured by such obligations or cash. The Fund invests in securities maturing in 397 days (13 months) or less (with certain exceptions), and the portfolio will have a dollar-weighted average maturity of 60 days or less and a dollar-weighted average life of 120 days or less. The Fund may invest in variable and floating rate instruments, and transact in securities on a when-issued, delayed delivery or forward commitment basis.

The securities purchased by the Fund are subject to the quality, diversification, and other requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended (the “Investment Company Act”), and other rules of the Securities and Exchange Commission.

Principal Risks of Investing in the Fund

Risk is inherent in all investing. 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 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. The following is a summary description of the principal risks of investing in the Fund. The relative significance of each risk factor below may change over time and you should review each risk factor carefully.

■

Interest Rate Risk — Interest rate risk is the risk that the value of a debt security may fall when interest rates rise. In general, the market price of debt securities with longer maturities will go up or down more in response to changes in interest rates than the market price of shorter-term securities. Due to fluctuations in interest rates, the market value of such securities may vary during the period shareholders own shares of the Fund. Very low or negative interest rates may magnify interest rate risk. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. The Fund may be subject to a greater risk of rising interest rates due to the recent period of historically low interest rates. The Federal Reserve has recently begun to raise the federal funds rate as part of its efforts to address rising inflation. There is a risk that interest rates will continue to rise, which will likely drive down the prices of bonds and other fixed-income securities. Changing interest rates may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Fund’s ability to achieve its investment objective.

■

Treasury Obligations Risk — Direct obligations of the U.S. Treasury have historically involved little risk of loss of principal if held to maturity. However, due to fluctuations in interest rates, the market value of such securities may

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	vary during the period shareholders own shares of the Fund. In addition, notwithstanding that U.S. Treasury obligations are backed by the full faith and credit of the United States, circumstances could arise that could prevent the timely payment of interest or principal, such as reaching the legislative “debt ceiling.” Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.
■	U.S. Government Obligations Risk — Certain securities in which the Fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States. In addition, circumstances could arise that could prevent the timely payment of interest or principal on U.S. Government obligations, such as reaching the legislative “debt ceiling.” Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.
■	Repurchase Agreements Risk — If the other party to a repurchase agreement defaults on its obligation under the agreement, the Fund may suffer delays and incur costs or lose money in exercising its rights under the agreement. If the seller fails to repurchase the security and the market value of the security declines, the Fund may lose money.
■	Credit Risk — Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will be unable or unwilling to make timely payments of interest and principal when due or otherwise honor their obligations. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also adversely affect the value of the Fund’s investment in that issuer.
■	Income Risk — Income risk is the risk that the Fund’s yield will vary as short-term securities in its portfolio mature and the proceeds are reinvested in securities with different interest rates.
■	Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.
	An outbreak of an infectious coronavirus (COVID-19) that was first detected in December 2019 developed into a global pandemic that has resulted in numerous disruptions in the market and has had significant economic impact leaving general concern and uncertainty. Although vaccines have been developed and approved for use by various governments, the duration of the pandemic and its effects cannot be predicted with certainty. Because the Fund invests in short-term instruments these events have caused some instruments to have declining yields, which may impair the results of the Fund if these conditions persisted. The impact of this coronavirus, and other epidemics and pandemics that may arise in the future, could affect the economies of many nations, individual companies and the market in general ways that cannot necessarily be foreseen at the present time.
■	Risk of Investing in the United States — Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
■	Stable Net Asset Value Risk — The Fund may not be able to maintain a stable net asset value (“NAV”) of $1.00 per share at all times. If the Fund fails to maintain a stable NAV (or if there is a perceived threat of such a failure), the Fund, along with other money market funds, could be subject to increased redemption activity.
■	Variable and Floating Rate Instrument Risk — Variable and floating rate securities provide for periodic adjustment in the interest rate paid on the securities. These securities may be subject to greater illiquidity risk than other fixed income securities, meaning the absence of an active market for these securities could make it difficult for the Fund to dispose of them at any given time.
■	When-Issued and Delayed Delivery Securities and Forward Commitments Risk — When-issued and delayed delivery securities and forward commitments involve the risk that the security the Fund buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the Fund may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security’s price.

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Performance Information

The Fund is a money market fund managed pursuant to the requirements of Rule 2a-7 under the Investment Company Act. Institutional Shares commenced operations on July 15, 2019. As a result, the returns shown below for Institutional Shares prior to July 15, 2019 are those of the Fund’s Investor A Shares. The performance of Institutional Shares would be substantially similar to Investor A Shares because Institutional Shares and Investor A Shares are invested in the same portfolio of securities and performance would differ only to the extent that Institutional Shares and Investor A Shares have different expenses. The actual returns of Institutional Shares would have been approximately the same as those of the Investor A Shares because Institutional Shares have the same expenses as the Investor A Shares. Investor C Shares commenced operations on August 10, 2018. As a result, the returns shown below for Investor C Shares prior to August 10, 2018 are those of the Fund’s Investor A Shares, adjusted to reflect the fees and expenses applicable to Investor C Shares. Effective January 4, 2016, the Fund changed its investment strategies in order to be categorized as a “government money market fund” under Rule 2a-7, as more fully described in “Fund Overview — Principal Investment Strategies of the Fund.” Performance for the periods shown below prior to January 4, 2016 is based on the prior investment strategy utilized by the Fund, which permitted investment in a wider range of money market securities and instruments and was not constrained by the requirement to invest at least 99.5% of the Fund’s assets in cash, U.S. Government securities and repurchase agreements secured by such securities or cash. The information below shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance is not an indication of future results. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information about the Fund’s performance can be obtained by visiting http://www.blackrock.com/cash or can be obtained by phone at (800) 441-7762.

BlackRock Summit Cash Reserves Fund
Investor A Shares

ANNUAL TOTAL RETURNS
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 0.78% (quarter ended December 31, 2022) and the lowest return for a quarter was 0.00% (quarter ended March 31, 2013). The year-to-date return as of June 30, 2023 was 2.15%.


For the periods ended 12/31/22 Average Annual Total Returns	1 Year	5 Years	10 Years
BlackRock Summit Cash Reserves — Investor A Shares	1.29%	0.86%	0.44%
BlackRock Summit Cash Reserves — Investor C Shares	(0.15)%	0.44%	(0.15)%
BlackRock Summit Cash Reserves — Institutional Shares	1.29%	0.85%	0.44%

To obtain the Fund’s current 7-day yield, call (800) 441-7762 or visit the Fund’s website at www.blackrock.com/cash.

Investment Manager

The Fund’s investment manager is BlackRock Advisors, LLC (previously defined as “BlackRock”).

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Purchase and Sale of Fund Shares

The Fund offers three different classes of shares in this prospectus.

You may purchase Investor A and Institutional Shares of the Fund or redeem shares of the Fund each day the New York Stock Exchange is open.

To purchase or redeem Investor A or Institutional Shares of the Fund you should contact your Financial Intermediary, or, if you hold your shares through the Fund, you should contact the Fund by phone at (800) 441-7762, by mail (c/o BlackRock Funds, P.O. Box 534429, Pittsburgh, Pennsylvania 15253-4429), or by the Internet at www.blackrock.com. You can acquire Investor C Shares only by exchange subject to certain eligibility requirements.

You can acquire Investor C Shares of the Fund by exchange from Investor C Shares of a fund advised by BlackRock or an affiliate. For more information, please see “Details About the Share Classes” on page 16 of the prospectus. To redeem Investor C Shares of the Fund you should contact the Fund’s transfer agent, BNY Mellon Investment Servicing (US) Inc., by phone at (800) 441-7762 or by mail c/o BlackRock P.O. Box 534429, Pittsburgh, Pennsylvania 15253-4429, or your financial intermediary or financial professional.

The Fund’s initial and subsequent investment minimums for Investor A and Institutional Shares generally are as follows, although the Fund may reduce or waive the minimums in some cases.

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	Investor A Shares	Institutional Shares
Minimum Initial Investment	$1,000 for all accounts except: • $50, if establishing an Automatic Investment Plan. • There is no investment minimum for employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs). • There is no investment minimum for certain fee-based programs.	There is no minimum initial investment for: • Employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs), state sponsored 529 college savings plans, collective trust funds, investment companies or other pooled investment vehicles, unaffiliated thrifts and unaffiliated banks and trust companies, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund’s distributor to purchase such shares. • Clients of Financial Intermediaries that: (i) charge such clients a fee for advisory, investment consulting, or similar services or (ii) have entered into an agreement with the Fund’s distributor to offer Institutional Shares through a no-load program or investment platform. • Clients investing through a self-directed IRA brokerage account program sponsored by a retirement plan record-keeper, provided that such program offers only mutual fund options and that the program maintains an account with the Fund on an omnibus basis. $2 million for individuals and “Institutional Investors,” which include, but are not limited to, endowments, foundations, family offices, local, city, and state governmental institutions, corporations and insurance company separate accounts who may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund’s distributor to purchase such shares. $1,000 for: • Clients investing through Financial Intermediaries that offer such shares on a platform that charges a transaction based sales commission outside of the Fund. • Tax-qualified accounts for insurance agents that are registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Fund’s distributor to offer Institutional Shares, and the family members of such persons.
Minimum Additional Investment	$50 for all accounts (with the exception of certain employer-sponsored retirement plans which may have a lower minimum).	No subsequent minimum.

Tax Information

The Fund’s dividends and distributions may be subject to U.S. federal income taxes and may be taxed as ordinary income or capital gains, unless you are a tax-exempt investor or are investing through a qualified tax-exempt plan described in section 401(a) of the Internal Revenue Code of 1986, as amended, in which case you may be subject to U.S. federal income tax when distributions are received from such tax-deferred arrangements.

Payments to Broker/Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a Financial Intermediary, the Fund and BlackRock Investments, LLC, the Fund’s distributor, or its affiliates may pay the Financial Intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the Financial Intermediary and your individual financial professional to recommend the Fund over another investment.

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Details About the Fund

Included in this prospectus are sections that tell you about buying and selling shares, management information, shareholder features of BlackRock Summit Cash Reserves Fund (the “Fund”) of BlackRock Financial Institutions Series Trust (the “Trust”) and your rights as a shareholder.

How the Fund Invests

The Fund is a government money market fund managed pursuant to Rule 2a-7 under the Investment Company Act of 1940, as amended (the “Investment Company Act”).

■	The Fund seeks to maintain a net asset value of $1.00 per share.
■	The Fund will maintain a dollar-weighted average maturity of 60 days or less and a dollar-weighted average life of 120 days or less. For a discussion of dollar-weighted average maturity and dollar-weighted average life, please see the Glossary on page 40.
■	Pursuant to Rule 2a-7, the Fund is subject to a “general liquidity requirement” that requires that the Fund hold securities that are sufficiently liquid to meet reasonably foreseeable shareholder redemptions in light of its obligations under Section 22(e) of the Investment Company Act regarding share redemptions and any commitments the Fund has made to shareholders. To comply with this general liquidity requirement, BlackRock Advisors, LLC (“BlackRock”) must consider factors that could affect the Fund’s liquidity needs, including characteristics of the Fund’s investors and their likely redemptions. Depending upon the volatility of its cash flows (particularly shareholder redemptions), this may require the Fund to maintain greater liquidity than would be required by the daily and weekly minimum liquidity requirements discussed below.
■	The Fund will not acquire any illiquid securities (i.e., securities that cannot be sold or disposed of in the ordinary course of business within seven days at approximately the value ascribed to them by the Fund) if, immediately following such purchase, more than 5% of the Fund’s total assets are invested in illiquid securities. The Fund will not acquire any security other than a daily liquid asset unless, immediately following such purchase, at least 10% of its total assets would be invested in daily liquid assets, and the Fund will not acquire any security other than a weekly liquid asset unless, immediately following such purchase, at least 30% of its total assets would be invested in weekly liquid assets. For a discussion of daily liquid assets and weekly liquid assets, please see the Glossary on page 40.
■	The Board of Trustees of the Trust has chosen not to subject the Fund to liquidity fees or temporary suspensions of redemptions due to declines in the Fund’s weekly liquid assets.

Investment Objective

The Fund seeks current income, preservation of capital and liquidity available from investing in a diversified portfolio of short-term money market securities.

Investment Process

In seeking to achieve the Fund’s investment objective, Fund management varies the kinds of short-term U.S. Government securities held in the Fund’s portfolio, as well as the Fund’s average maturity. Fund management decides which securities to buy and sell, as well as whether to enter into repurchase agreements, based on its assessment of their relative values and future interest rates.

Principal Investment Strategies

The U.S. Government securities in which the Fund may invest include:

■

Repurchase Agreements — Repurchase agreements are transactions in which the Fund purchases a class of securities with the obligation to resell the securities shortly thereafter at a specified price which reflects interest payable to the Fund. The Fund may engage in repurchase agreements secured by U.S. Treasury bills, notes and other obligations issued or guaranteed as to principal and interest by the U.S. Government, its agencies or instrumentalities and cash.

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■	U.S. Treasury Obligations — Obligations that are direct obligations of the U.S. Treasury. These also include Treasury Receipts where the principal and interest components are traded separately under the Separate Trading of Registered Interest and Principal of Securities (“STRIPS”) Program.
■	U.S. Government Obligations — Obligations issued or guaranteed by the U.S. Government or its agencies, authorities, instrumentalities and sponsored enterprises, and related custodial receipts.
■	Variable and Floating Rate Instruments — Variable and floating rate securities provide for periodic adjustment in the interest rate paid on the securities. These securities may be subject to greater illiquidity risk than other fixed income securities, meaning the absence of an active market for these securities could make it difficult for the Fund to dispose of them at any given time.
■	When-Issued and Delayed Settlement Transactions —The purchase or sale of securities on a when-issued basis, on a delayed delivery basis or through a forward commitment involves the purchase or sale of securities by the Fund at an established price with payment and delivery taking place in the future. The Fund enters into these transactions to obtain what is considered an advantageous price to the Fund at the time of entering into the transaction.

Other Strategies

In addition to the principal strategies discussed above, the Fund may also invest or engage in the following investments/strategies:

■	Borrowing — The Fund may borrow from banks only to meet redemptions.
■	Illiquid Investments—The Fund may invest up to 5% of its total assets in illiquid securities that it cannot sell within seven days at approximately current value.
■	Investment Companies — The Fund has the ability to invest in other investment companies, such as exchange traded funds, money market funds, unit investment trusts, and open-end and closed-end funds, subject to the applicable limits under the Investment Company Act and the rules thereunder. The Fund may invest in affiliated investment companies including affiliated money market funds and affiliated exchange-traded funds.
■	Restricted Securities — Restricted securities are securities that cannot be offered for public resale unless registered under the applicable securities laws or that have a contractual restriction that prohibits or limits their resale. They may include Rule 144A securities, which are privately placed securities that can be resold to qualified institutional buyers but not to the general public, and securities of U.S. and non-U.S. issuers that are offered pursuant to Regulation S under the Securities Act of 1933, as amended.
■	Securities Lending — The Fund may lend securities with a value up to 33¹⁄3% of its total assets to financial institutions that provide cash or securities issued or guaranteed by the U.S. Government as collateral.

Investment Risks

Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. Your investment may not perform as well as other similar investments. 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 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. The following is a description of certain risks of investing in the Fund. The order of the below risk factors does not indicate the significance of any particular risk factor.

Principal Risks of Investing in the Fund

■	Credit Risk — Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will be unable or unwilling to make timely payments of interest and principal when due or otherwise honor their obligations. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also adversely affect the value of the Fund’s investment in that issuer. The degree of credit risk depends on both the financial condition of the issuer and the terms of the obligation.
■	Income Risk — The Fund’s yield will vary as the short-term securities in its portfolio mature and the proceeds are reinvested in securities with different interest rates.
■	Interest Rate Risk — Interest rate risk is the risk that the value of a debt security may fall when interest rates rise. In general, the market price of debt securities with longer maturities will go up or down more in response to changes in interest rates than the market price of shorter-term securities. Due to fluctuations in interest rates, the market value of such securities may vary during the period shareholders own shares of the Fund. Very low or negative

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	interest rates may magnify interest rate risk. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. The Fund may be subject to a greater risk of rising interest rates due to the recent period of historically low interest rates. The Federal Reserve has recently begun to raise the federal funds rate as part of its efforts to address rising inflation. There is a risk that interest rates will continue to rise, which will likely drive down the prices of bonds and other fixed-income securities. Changing interest rates may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Fund’s ability to achieve its investment objective.
■	Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.
	An outbreak of an infectious coronavirus (COVID-19) that was first detected in December 2019 developed into a global pandemic that has resulted in numerous disruptions in the market and has had significant economic impact leaving general concern and uncertainty. Although vaccines have been developed and approved for use by various governments, the duration of the pandemic and its effects cannot be predicted with certainty. Because the Fund invests in short-term instruments these events have caused some instruments to have declining yields, which may impair the results of the Fund if these conditions persisted. The impact of this coronavirus, and other epidemics and pandemics that may arise in the future, could affect the economies of many nations, individual companies and the market in general ways that cannot necessarily be foreseen at the present time.
■	Repurchase Agreements Risk — If the other party to a repurchase agreement defaults on its obligation under the agreement, the Fund may suffer delays and incur costs or lose money in exercising its rights under the agreement. If the seller fails to repurchase the security and the market value of the security declines, the Fund may lose money.
■	Risk of Investing in the United States — A decrease in imports or exports, changes in trade regulations, inflation and/or an economic recession in the United States may have a material adverse effect on the U.S. economy and the securities listed on U.S. exchanges. Proposed and adopted policy and legislative changes in the United States are changing many aspects of financial, commercial, public health, environmental, and other regulation and may have a significant effect on U.S. markets generally, as well as on the value of certain securities. Governmental agencies project that the United States will continue to maintain elevated public debt levels for the foreseeable future. Although elevated debt levels do not necessarily indicate or cause economic problems, elevated public debt service costs may constrain future economic growth.
	The United States has developed increasingly strained relations with a number of foreign countries. If relations with certain countries deteriorate, it could adversely affect U.S. issuers as well as non-U.S. issuers that rely on the United States for trade. The United States has also experienced increased internal political discord, as well as significant challenges in managing and containing the outbreak of COVID-19. If these trends were to continue, it may have an adverse impact on the U.S. economy and the issuers in which the Fund invests.
■	Stable Net Asset Value Risk — The Fund may not be able to maintain a stable net asset value (“NAV”) of $1.00 per share at all times. If the Fund fails to maintain a stable NAV (or if there is a perceived threat of such a failure), the Fund, along with other money market funds, could be subject to increased redemption activity.
■	Treasury Obligations Risk — Direct obligations of the U.S. Treasury have historically involved little risk of loss of principal if held to maturity. However, due to fluctuations in interest rates, the market value of such securities may vary during the period shareholders own shares of the Fund. In addition, notwithstanding that U.S. Treasury obligations are backed by the full faith and credit of the United States, circumstances could arise that could prevent the timely payment of interest or principal, such as reaching the legislative “debt ceiling.” Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.
■	U.S. Government Obligations Risk — Not all U.S. Government securities are backed by the full faith and credit of the United States. Obligations of certain agencies, authorities, instrumentalities and sponsored enterprises of the U.S. Government are backed by the full faith and credit of the United States (e.g., the Government National Mortgage Association); other obligations are backed by the right of the issuer to borrow from the U.S. Treasury (e.g., the Federal Home Loan Banks) and others are supported by the discretionary authority of the U.S. Government to purchase an agency’s obligations. Still others are backed only by the credit of the agency, authority,

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	instrumentality or sponsored enterprise issuing the obligation. No assurance can be given that the U.S. Government would provide financial support to any of these entities if it is not obligated to do so by law. In addition, circumstances could arise that could prevent the timely payment of interest or principal on U.S. Government obligations, such as reaching the legislative “debt ceiling.” Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.
■	Variable and Floating Rate Instrument Risk — Variable and floating rate securities provide for periodic adjustment in the interest rate paid on the securities. These securities may be subject to greater illiquidity risk than other fixed income securities, meaning the absence of an active market for these securities could make it difficult for the Fund to dispose of them at any given time.
■	When-Issued and Delayed Delivery Securities and Forward Commitments Risk — When-issued and delayed delivery securities and forward commitments involve the risk that the security the Fund buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the Fund may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security’s price.

Other Risks of Investing in the Fund

The Fund may also be subject to certain other non-principal risks associated with its investments and investment strategies, including:

■	Borrowing Risk — Borrowing may exaggerate changes in the net asset value of Fund shares and in the return on the Fund’s portfolio. Borrowing will cost the Fund interest expense and other fees. The costs of borrowing may reduce the Fund’s return. Borrowing may cause the Fund to liquidate positions when it may not be advantageous to do so to satisfy its obligations.
■	Cyber Security Risk — Failures or breaches of the electronic systems of the Fund, the Fund’s adviser, distributor, and other service providers, or the issuers of securities in which the Fund invests have the ability to cause disruptions and negatively impact the Fund’s business operations, potentially resulting in financial losses to the Fund and its shareholders. While the Fund has established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Furthermore, the Fund cannot control the cyber security plans and systems of the Fund’s service providers or issuers of securities in which the Fund invests.
■	Expense Risk — Fund expenses are subject to a variety of factors, including fluctuations in the Fund’s net assets. Accordingly, actual expenses may be greater or less than those indicated. For example, to the extent that the Fund’s net assets decrease due to market declines or redemptions, the Fund’s expenses will increase as a percentage of Fund net assets. During periods of high market volatility, these increases in the Fund’s expense ratio could be significant.
■	Illiquid Investments Risk — The Fund’s illiquid investments may reduce the returns of the Fund because it may be difficult to sell the illiquid investments at an advantageous time or price. The Fund may be unable to pay redemption proceeds within the time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons.
■	Investment in Other Investment Companies Risk — As with other investments, investments in other investment companies, including exchange traded funds, are subject to market and selection risk. In addition, if the Fund acquires shares of investment companies, including ones affiliated with the Fund, shareholders bear both their proportionate share of expenses in the Fund (including management and advisory fees) and, indirectly, the expenses of the investment companies (to the extent not offset by BlackRock through waivers). To the extent the Fund is held by an affiliated fund, the ability of the Fund itself to hold other investment companies may be limited.
■	Large Shareholder and Large-Scale Redemption Risk — Certain shareholders, including a third-party investor, the Fund’s adviser or an affiliate of the Fund’s adviser, or another entity, may from time to time own or manage a substantial amount of Fund shares or may invest in the Fund and hold its investment for a limited period of time. There can be no assurance that any large shareholder or large group of shareholders would not redeem their investment or that the size of the Fund would be maintained. Redemptions of a large number of Fund shares by these shareholders may adversely affect the Fund’s liquidity and net assets. These redemptions may force the Fund to sell portfolio securities to meet redemption requests when it might not otherwise do so, which may negatively impact the Fund. In addition, large redemptions can result in the Fund’s current expenses being allocated over a smaller asset base, which generally could result in an increase in the Fund’s expense ratio.
■	Restricted Securities Risk — Limitations on the resale of restricted securities may have an adverse effect on their marketability, and may prevent the Fund from disposing of them promptly at advantageous prices. Restricted securities may not be listed on an exchange and may have no active trading market. In order to sell such securities, the Fund may have to bear the expense of registering the securities for resale and the risk of substantial delays in

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Account Information

How to Choose the Share Class that Best Suits Your Needs

The Fund currently offers multiple share classes (Investor A, Investor C and Institutional Shares in this prospectus), each with its own sales charge and expense structure, allowing you to invest in the way that best suits your needs. Investor C Shares are available only by exchange. Each share class represents an ownership interest in the same investment portfolio of the Fund. When you choose your class of shares, you should consider the size of your investment and how long you plan to hold your shares. Either your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock and its affiliates) (each a “Financial Intermediary”) can help you determine which share class is best suited to your personal financial goals. Investor A and Investor C Shares are sometimes referred to herein collectively as “Investor Shares.”

If you exchange into Investor C Shares, you will invest the full amount of your purchase price, but you will be subject to a distribution fee of 0.75% per year under a plan adopted pursuant to Rule 12b-1 under the Investment Company Act. Because these fees are paid out of the Fund’s assets on an ongoing basis, over time these fees increase the cost of your investment and may cost you more than paying other types of sales charges. Since all Investor C Shares must be purchased in an exchange transaction for Investor C Shares of a non-money market fund advised by BlackRock or its affiliates (each a “Non-Money Market BlackRock Fund”), a contingent deferred sales charge (“CDSC”) of 1.00% may apply to certain redemptions of the Fund’s Investor C Shares. The Investor C Shares CDSC is only charged upon redemptions of Investor C Shares within one year after you originally acquired the Investor C Shares of the Non-Money Market BlackRock Fund, unless you qualify for a waiver. There is no CDSC charged on redemptions if you have owned your Investor C Shares for more than one year (as measured from your original purchase of Investor C Shares of the Non-Money Market BlackRock Fund that you exchanged into Investor C Shares of the Fund). Classes with lower expenses will have higher net asset values and dividends relative to other share classes.

If you select Institutional Shares, you will not pay any sales charge. However, only certain investors may buy Institutional Shares.

The Fund’s shares are distributed by BlackRock Investments, LLC (the “Distributor”), an affiliate of BlackRock.

The table on the following pages summarizes key features of each of the share classes offered by this prospectus.

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Share Classes at a Glance¹

	Investor A Shares	Investor C Shares	Institutional Shares
Availability	Generally available through Financial Intermediaries. Also available by exchange to participants holding Investor A Shares (the “exchanged shares”) through the exchange privilege available to investors in certain mutual funds sponsored and advised by BlackRock or its affiliates (“BlackRock”).	Limited to exchanges from Investor C Shares of the Non-Money Market BlackRock Funds. Must be held through a Financial Intermediary.	Limited to certain investors, including: • Individuals and “Institutional Investors,” which include, but are not limited to, endowments, foundations, family offices, local, city and state governmental institutions, corporations and insurance company separate accounts, who may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares. • Employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs), state sponsored 529 college savings plans, collective trust funds, investment companies or other pooled investment vehicles, unaffiliated thrifts and unaffiliated banks and trust companies, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares. • Employees, officers and directors/trustees of BlackRock or its affiliates and immediate family members of such persons, if they open an account directly with BlackRock. • Participants in certain programs sponsored by BlackRock or its affiliates or other Financial Intermediaries. • Tax-qualified accounts for insurance agents that are registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Distributor to offer Institutional Shares, and the family members of such persons. • Clients investing through Financial Intermediaries that have entered into an agreement with the Distributor to offer such shares on a platform that charges a transaction based sales commission outside of the Fund. • Clients investing through a self-directed IRA brokerage account program sponsored by a retirement plan record-keeper, provided that such program offers only mutual fund options and that the program maintains an account with the Fund on an omnibus basis.

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	Investor A Shares	Investor C Shares	Institutional Shares
Minimum Investment	$1,000 for all accounts except: • $50, if establishing an Automatic Investment Plan (“AIP”). • There is no investment minimum for employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs). • There is no investment minimum for certain fee-based programs.	$1,000 for all accounts except: • There is no investment minimum for employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs). • There is no investment minimum for certain fee-based programs.	There is no investment minimum for: • Employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs), state sponsored 529 college savings plans, collective trust funds, investment companies or other pooled investment vehicles, unaffiliated thrifts and unaffiliated banks and trust companies. • Employees, officers and directors/trustees of BlackRock or its affiliates and immediate family members of such persons, if they open an account directly with BlackRock. • Clients of Financial Intermediaries that: (i) charge such clients a fee for advisory, investment consulting, or similar services or (ii) have entered into an agreement with the Distributor to offer Institutional Shares through a no-load program or investment platform. • Clients investing through a self-directed IRA brokerage account program sponsored by a retirement plan record-keeper, provided that such program offers only mutual fund options and that the program maintains an account with the Fund on an omnibus basis. $2 million for individuals and Institutional Investors. $1,000 investment minimum for: • Clients investing through Financial Intermediaries that offer such shares on a platform that charges a transaction based sales commission outside of the Fund. • Tax-qualified accounts for insurance agents that are registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Distributor to offer Institutional Shares, and the family members of such persons.
Initial Sales Charge?	No. Entire purchase price is invested in shares of the Fund. However, if you exchange Investor A Shares of the Fund for Investor A Shares of another mutual fund sponsored and advised by BlackRock or its affiliates (“BlackRock Fund”) with an initial sales charge that is higher than the initial sales charge on the exchanged shares, you will pay the difference upon the exchange.	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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	Investor A Shares	Investor C Shares	Institutional Shares
Deferred Sales Charge?	No. (A CDSC may apply to certain redemptions of Investor A Shares purchased in an exchange transaction for Investor A Shares of a fund advised by BlackRock or its affiliates where no initial sales charge was paid at time of purchase of such fund (each, an “Investor A Load- Waived BlackRock Fund”) that assesses a CDSC (which may be charged for purchases of $1 million or more (lesser amounts may apply depending on the Investor A Load-Waived BlackRock Fund) that are redeemed within 18 months or within a shorter holding period as applicable)).	Since all Investor C Shares must be purchased in an exchange transaction for Investor C Shares of a Non-Money Market BlackRock Fund, a CDSC of 1.00% will apply to redemptions of the Fund’s Investor C Shares if the redemption is within one year of your purchase of the Non-Money Market BlackRock Fund Investor C Shares, unless you qualify for a waiver.	No.
Distribution and Service (12b-1) Fees?	No.	0.75% Annual Distribution Fee.	No.
Redemption Fees?	No. If you exchange into the Fund from a fund that imposes a redemption fee, that redemption fee may apply.	No. If you exchange into the Fund from a fund that imposes a redemption fee, that redemption fee may apply.	No. If you exchange into the Fund from a fund that imposes a redemption fee, that redemption fee may apply.
Conversion to Investor A Shares?	N/A	Yes, automatically approximately ten years after the date of purchase. It is the Financial Intermediary’s responsibility to ensure that the shareholder is credited with the proper holding period. As of the Effective Date (as defined below), certain Financial Intermediaries, including group retirement recordkeeping platforms, may not have been tracking such holding periods and therefore may not be able to process such conversions. In such instances, the automatic conversion of Investor C Shares to Investor A Shares will occur approximately ten years after the Effective Date.	No.
Advantage	Generally available to most investors. Not subject to ongoing distribution fees.	Not applicable.	No up-front sales charge so you start off owning more shares. No distribution or service fees.
Disadvantage	Not applicable.	Limited availability.	Limited availability.

¹	Please see “Details About the Share Classes” for more information about each share class.

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Details About the Share Classes

The following pages will cover the additional details of each share class, including the Institutional Shares requirements, reduced sales charge information, Investor C Share CDSC information, and sales charge waivers.

The availability of certain sales charge waivers and reductions will depend on whether you purchase shares of an Investor A Load-Waived BlackRock Fund or Non-Money Market BlackRock Fund, as applicable, directly from the Investor A Load-Waived BlackRock Fund or Non-Money Market BlackRock Fund, as applicable, through a Financial Intermediary before exchanging into shares of the Fund. Financial Intermediaries may have different policies and procedures regarding the availability of deferred sales charge waivers, which are discussed below. In all instances, it is your responsibility to notify the applicable Investor A Load-Waived BlackRock Fund or Non-Money Market BlackRock Fund, as applicable, your Financial Intermediary at the time of purchase of any relationship or other facts qualifying you for sales charge waivers or reductions. For waivers and discounts not available through a particular Financial Intermediary, shareholders will have to purchase Investor A Load-Waived BlackRock Fund or Non-Money Market BlackRock Fund, as applicable, shares directly from the Investor A Load-Waived BlackRock Fund or Non-Money Market BlackRock Fund, as applicable, or through another Financial Intermediary to receive these waivers or reductions. Please see the “Intermediary-Defined Sales Charge Waiver Policies” section beginning on page A-1 of the Fund’s prospectus, as applicable, to determine any sales charge waivers and reductions that may be available to you through your Financial Intermediary.

More information about existing sales charge reductions and waivers is available free of charge in a clear and prominent format via hyperlink at www.blackrock.com and in the SAI, which is available on the website or on request.

Investor A Shares at Net Asset Value

There is no initial sales charge or CDSC on Investor A Shares of the Fund purchased directly. However, a CDSC of up to 1.00% may apply to certain redemptions of the Fund’s Investor A Shares purchased in an exchange transaction for Investor A Shares of an Investor A Load-Waived BlackRock Fund where no initial sales charge was paid at time of purchase of such Investor A Load-Waived BlackRock Fund as part of an investment of $1,000,000 (lesser amounts may apply depending on the Investor A Load-Waived BlackRock Fund) or more. If the Investor A Load-Waived BlackRock Fund from which you exchanged your shares charges a CDSC less than 1.00%, the lesser CDSC will apply to redemptions of Investor A Shares of the Fund. The CDSC of up to 1.00% is charged on the lesser of the original cost of the shares being redeemed or your redemption proceeds. The Investor A Shares CDSC is only charged upon redemptions of Investor A Shares within 18 months after you originally acquired such Investor A Shares of the Investor A Load-Waived BlackRock Fund (a shorter holding period may apply depending on the Investor A Load-Waived BlackRock Fund), unless you qualify for a waiver. There is no CDSC charged on redemptions if you have owned your Investor A Shares for more than 18 months (or for a shorter holding period, as applicable) as measured from your original purchase of Investor A Shares that you exchanged into Investor A Shares of the Fund. Such CDSC may be waived in connection with certain fee-based programs. For a discussion on waivers, see “Contingent Deferred Sales Charge Waivers.” Any CDSC paid upon certain redemptions of Investor A Shares expressed as a percentage of the applicable redemption amount may be higher or lower than the charge described due to rounding.

See the “Intermediary-Defined Sales Charge Waiver Policies” section beginning on page A-1 of the Fund’s prospectus, to the extent applicable, for CDSC reductions and waivers that may be available to customers of certain Financial Intermediaries.

Investor C Shares — Deferred Sales Charge Option

If you exchange into Investor C Shares, you do not pay an initial sales charge at the time of exchange. However, if you redeem your Investor C Shares within one year after purchase of shares of a Non-Money Market BlackRock Fund, you may be required to pay a deferred sales charge of 1.00%. The charge will apply to the lesser of the original cost of shares being redeemed or the proceeds of your redemption. When you redeem Investor C Shares, the redemption order is processed so that the lowest deferred sales charge is charged. Investor C Shares that are not subject to the deferred sales charge are redeemed first. In addition, you will not be charged a deferred sales charge when you redeem shares that you acquire through reinvestment of Fund dividends or capital gains. Any CDSC paid on the redemptions of Investor C Shares expressed as a percentage of the applicable redemption amount may be higher or lower than the charge described due to rounding.

Effective November 23, 2020 (the “Effective Date”), Investor C Shares will automatically convert to Investor A Shares approximately eight years after the date of purchase. It is the Financial Intermediary’s responsibility to ensure that the shareholder is credited with the proper holding period. As of the Effective Date, certain Financial Intermediaries, including group retirement recordkeeping platforms, may not have been tracking such holding periods and therefore may not be able to process such conversions. In such instances, the automatic conversion of Investor C Shares to Investor A Shares will occur approximately eight years after the Effective Date. The automatic conversion of Investor C

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Shares to Investor A Shares is not a taxable event for Federal income tax purposes. Please consult your Financial Intermediary for additional information.

In addition, accounts that do not have a Financial Intermediary associated with them are not eligible to hold Investor C Shares, and any Investor C Shares held in such accounts will be automatically converted to Investor A Shares.

See the “Intermediary-Defined Sales Charge Waiver Policies” section beginning on page A-1 of the Fund’s prospectus, to the extent applicable, for sales charge reductions and waivers that may be available to customers of certain Financial Intermediaries.

You will also pay distribution fees of 0.75% for Investor C Shares each year. Because these fees are paid out of the Fund’s assets on an ongoing basis, over time these fees increase the cost of your investment and may cost you more than paying other types of sales charges. The Distributor uses the money that it receives from the deferred sales charges and the distribution fees to cover the costs of marketing, advertising and compensating the Financial Intermediary who assists you in purchasing shares.

The Distributor currently pays dealers a sales concession of 1.00% of the purchase price of Investor C Shares of a Non-Money Market BlackRock Fund from its own resources at the time of sale. The Distributor pays the annual Investor C Shares distribution fee as an ongoing concession to dealers for Investor C Shares held for over a year measured from the time Non-Money Market BlackRock Fund shares were originally purchased and normally retains the Investor C Shares distribution fee during the first year after purchase. For certain employer-sponsored retirement plans, the Distributor will pay the full Investor C Shares distribution fee to dealers beginning in the first year after purchase in lieu of paying the sales concession. This may depend on the policies, procedures and trading platforms of your Financial Intermediary; consult your financial adviser.

Contingent Deferred Sales Charge Waivers

The deferred sales charge relating to Investor Shares may be reduced or waived in certain circumstances, such as:

■	Redemptions of shares purchased through certain employer-sponsored retirement plans and rollovers of current investments in the Fund through such plans;
■	Exchanges pursuant to the exchange privilege, as described in “How to Buy, Sell, Exchange and Transfer Shares — How to Exchange Shares or Transfer Your Account”;
■	Redemptions made in connection with minimum required distributions from IRA or 403(b)(7) accounts due to the shareholder reaching the age of 72;
■	Certain post-retirement withdrawals from an IRA or other retirement plan if you are over 59½ years old and you purchased your shares prior to October 2, 2006;
■	Redemptions made with respect to certain retirement plans sponsored by the Fund, BlackRock or an affiliate;
■	Redemptions resulting from shareholder death as long as the waiver request is made within one year of death or, if later, reasonably promptly following completion of probate (including in connection with the distribution of account assets to a beneficiary of the decedent);
■	Withdrawals resulting from shareholder disability (as defined in the Internal Revenue Code) as long as the disability arose subsequent to the purchase of the shares;
■	Involuntary redemptions made of shares in accounts with low balances;
■	Certain redemptions made through the Systematic Withdrawal Plan (“SWP”) offered by the Fund, BlackRock or an affiliate;
■	Redemptions related to the payment of BNY Mellon Investment Servicing Trust Company custodial IRA fees; and
■	Redemptions when a shareholder can demonstrate hardship, in the absolute discretion of the Fund.

Right of Accumulation

Investors have a “right of accumulation” under which any of the following may be combined with the amount of the current purchase in determining whether an investor qualifies for a breakpoint and a reduced front-end sales charge:

i.	The current value of an investor’s existing Investor A and A1, Investor C, Investor P, Institutional, Class K and Premier Shares in most BlackRock Funds,

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ii.	The current value of an investor’s existing shares of certain unlisted closed-end management investment companies sponsored and advised by BlackRock or its affiliates and
iii.	The investment in the BlackRock CollegeAdvantage 529 Program by the investor or by or on behalf of the investor’s spouse and children.

Financial Intermediaries may value current holdings of their customers differently for purposes of determining whether an investor qualifies for a breakpoint and a reduced front-end sales charge, although customers of the same Financial Intermediary will be treated similarly. In order to use this right, the investor must alert BlackRock to the existence of any previously purchased shares.

Institutional Shares

Institutional Shares are not subject to any sales charge. Only certain investors are eligible to buy Institutional Shares. Your Financial Intermediary can help you determine whether you are eligible to buy Institutional Shares. The Fund may permit a lower initial investment for certain investors if their purchase, combined with purchases by other investors received together by the Fund, meets the minimum investment requirement.

Institutional Shares may also be available on certain brokerage platforms. An investor transacting in Institutional Shares on such brokerage platforms through a broker acting as an agent for the investor may be required to pay a commission and/or other forms of compensation to the broker. Shares of the Fund are available in other share classes that have different fees and expenses.

Eligible Institutional Share investors include the following:

■	Individuals and “Institutional Investors” with a minimum initial investment of $2 million who may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares;
■	Clients of Financial Intermediaries that: (i) charge such clients a fee for advisory, investment consulting, or similar services or (ii) have entered into an agreement with the Distributor to offer Institutional Shares through a no-load program or investment platform, in each case, with no minimum initial investment;
■	Clients investing through Financial Intermediaries that have entered into an agreement with the Distributor to offer such shares on a platform that charges a transaction based sales commission outside of the Fund, with a minimum initial investment of $1,000;
■	Employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs), state sponsored 529 college savings plans, collective trust funds, investment companies or other pooled investment vehicles, unaffiliated thrifts and unaffiliated banks and trust companies, each of which is not subject to any minimum initial investment and may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares;
■	Trust department clients of Bank of America, N.A. and its affiliates for whom they (i) act in a fiduciary capacity (excluding participant directed employee benefit plans); (ii) otherwise have investment discretion; or (iii) act as custodian for at least $2 million in assets, who are not subject to any minimum initial investment;
■	Holders of certain Bank of America Corporation (“BofA Corp.”) sponsored unit investment trusts (“UITs”) who reinvest dividends received from such UITs in shares of the Fund, who are not subject to any minimum initial investment;
■	Employees, officers and directors/trustees of BlackRock, Inc., BlackRock Funds, BofA Corp., Barclays PLC or their respective affiliates and immediate family members of such persons, if they open an account directly with BlackRock, who are not subject to any minimum initial investment;
■	Tax-qualified accounts for insurance agents that are registered representatives of an insurance company’s broker-dealer that has entered into an agreement with the Distributor to offer Institutional Shares, and the family members of such persons; and
■	Clients investing through a self-directed IRA brokerage account program sponsored by a retirement plan record-keeper, provided that such program offers only mutual fund options and that the program maintains an account with the Fund on an omnibus basis.

The Fund reserves the right to modify or waive the above-stated policies at any time.

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Distribution and Shareholder Servicing Payments

Plan Payments

The Fund has adopted a distribution plan (the “Plan”) that allows the Fund to pay distribution fees for the sale of its shares.

The distribution fees payable pursuant to the Plan are paid to compensate Financial Intermediaries for distribution and sales support services and related expenses provided in connection with the sale of Investor C Shares. Because the fees paid by the Fund under the Plan are paid out of the Fund’s assets on an ongoing basis, over time these fees will increase the cost of your investment in the Investor C Shares of the Fund and may cost you more than paying other types of sales charges.

Other Payments by the Fund

In addition to fees that the Fund may pay to a Financial Intermediary pursuant to the Plan and fees the Fund pays to its transfer agent, BlackRock, on behalf of the Fund, may enter into non-Plan agreements with affiliated and unaffiliated Financial Intermediaries pursuant to which the Fund will pay a Financial Intermediary for administrative, networking, recordkeeping, sub-transfer agency, sub-accounting and/or shareholder services. These non-Plan payments are generally based on either (1) a percentage of the average daily net assets of Fund shareholders serviced by a Financial Intermediary or (2) a fixed dollar amount for each account serviced by a Financial Intermediary. The aggregate amount of these payments may be substantial.

Other Payments by BlackRock

From time to time, BlackRock, the Distributor or their affiliates also may pay a portion of the fees for administrative, networking, recordkeeping, sub-transfer agency, sub-accounting and shareholder services described above at its or their own expense and out of its or their profits. BlackRock, the Distributor and their affiliates may also compensate affiliated and unaffiliated Financial Intermediaries for the sale and distribution of shares of the Fund. These payments would be in addition to the Fund payments described in this prospectus and may be a fixed dollar amount, may be based on the number of customer accounts maintained by the Financial Intermediary, may be based on a percentage of the value of shares sold to, or held by, customers of the Financial Intermediary or may be calculated on another basis. The aggregate amount of these payments by BlackRock, the Distributor and their affiliates may be substantial and, in some circumstances, may create an incentive for a Financial Intermediary, its employees or associated persons to recommend or sell shares of the Fund to you.

Please contact your Financial Intermediary for details about payments it may receive from the Fund or from BlackRock, the Distributor or their affiliates. For more information, see the SAI.

How to Buy, Sell, Exchange and Transfer Shares

The following chart summarizes how to buy, sell, exchange and transfer shares through your Financial Intermediary. You may also sell, exchange and transfer shares through the transfer agent, if your account is held directly with the transfer agent. To learn more about selling or exchanging shares through the transfer agent, call (800) 441-7762. Because the selection of a mutual fund involves many considerations, your Financial Intermediary may help you with this decision.

With certain limited exceptions, the Fund is generally available only to investors residing in the United States and may not be distributed by a foreign Financial Intermediary. Under this policy, in order to accept new accounts or additional investments (including by way of exchange from another BlackRock Fund) into existing accounts, the Fund generally requires that (i) a shareholder that is a natural person be a U.S. citizen or resident alien, in each case residing within the United States or a U.S. territory (including APO/FPO/DPO addresses), and have a valid U.S. taxpayer identification number, and (ii) a Financial Intermediary or a shareholder that is an entity be domiciled in the United States and have a valid U.S. taxpayer identification number or be domiciled in a U.S. territory and have a valid U.S. taxpayer identification number or IRS Form W-8. Any existing account that is updated to reflect a non-U.S. address will also be restricted from making additional investments.

The Fund may reject any purchase order, modify or waive the minimum initial or subsequent investment requirements for any shareholders and suspend and resume the sale of shares of the Fund at any time, for any reason. In addition, the Fund may waive certain requirements regarding the purchase, sale, exchange or transfer of shares described below and on the following pages.

Under certain circumstances, if no activity occurs in an account within a time period specified by state law, a shareholder’s shares in the Fund may be transferred to that state.

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How to Buy Shares

	Your Choices	Important Information For You to Know
Initial Purchase	First, select the share class appropriate for you	Refer to the “Share Classes at a Glance” table in this prospectus (be sure to read this prospectus carefully). When you place your initial order, you must indicate which share class you select (if you do not specify a share class and do not qualify to purchase Institutional Shares, you will receive Investor A Shares). Certain factors, such as the amount of your investment, your time frame for investing, and your financial goals, may affect which share class you choose. Your financial representative can help you determine which share class is appropriate for you. You can acquire Investor C Shares only by exchange subject to certain eligibility requirements.
	Next, determine the amount of your investment	Refer to the minimum initial investment in the “Share Classes at a Glance” table of this prospectus. See “Account Information — Details About the Share Classes” for information on a lower initial investment requirement for certain Fund investors if their purchase, combined with purchases by other investors received together by the Fund, meets the minimum investment requirement. You can acquire Investor C Shares of the Fund only by exchange from Investor C Shares of a Non-Money Market BlackRock Fund.
	Have your Financial Intermediary submit your purchase or exchange order	The Fund’s investments are valued based on the amortized cost method described in the Statement of Additional Information. You may request a Financial Intermediary that has entered into a selected dealer agreement with the Distributor to place a purchase order for your account. See below for more details. The price of your Shares will be the net asset value next calculated after your order becomes effective. Share purchase orders are effective on the date Federal funds become available to the Fund. For Investor A and Institutional Shares orders, if Federal funds are available to the Fund prior to the close of the federal funds wire (normally 6:45 p.m. (Eastern time)) on any business day, the order will be effective on that day. For Investor C Shares exchange orders, if Federal funds are available to the Fund prior to the determination of net asset value (generally 4:00 p.m. Eastern time) on any business day, the order will be effective on that day. Certain Financial Intermediaries, however, may require submission of orders prior to that time. Shares purchased will begin accruing dividends on the day following the date your purchase becomes effective. NAV is calculated separately for each class of shares of the Fund as of the close of business on the New York Stock Exchange (the “Exchange”), generally 4:00 p.m. (Eastern time), each business day. Shares will not be priced on days the Exchange is closed. The Fund may elect, in its discretion if it is determined to be in shareholders’ best interest, to be open on days when the Exchange is closed due to an emergency. Purchase or exchange orders placed after 4:00 p.m. (Eastern time) will be priced at the NAV determined on the next business day. A broker-dealer or financial institution maintaining the account in which you hold shares may charge a separate account, service or transaction fee on the purchase or sale of Fund shares that would be in addition to the fees and expenses shown in the Fund’s “Fees and Expenses” table. The Fund may reject any order to buy shares and may suspend the sale of shares at any time. Certain Financial Intermediaries may charge a processing fee to confirm a purchase.
	Or contact BlackRock (for accounts held directly with BlackRock)	To purchase shares directly from BlackRock, call (800) 441-7762 and request a new account application. Mail the completed application along with a check, if applicable payable to BlackRock Funds to the Transfer Agent, at the address on the application.

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	Your Choices	Important Information For You to Know
Add to Your Investment	Purchase additional shares (Investor A and Institutional Shares only)	For Investor A Shares, the minimum investment for additional purchases is generally $50 for all accounts (with the exception of certain employer-sponsored retirement plans which may have a lower minimum for additional purchase). The minimums for additional purchases may be waived under certain circumstances. Institutional Shares have no minimum for additional purchases.
	Have your Financial Intermediary submit your purchase order for additional shares (Investor A and Institutional Shares only)	To purchase additional shares you may contact your Financial Intermediary. For more details on purchasing by Internet see below.
	Or contact BlackRock (for accounts held directly with BlackRock) (Investor A and Institutional Shares only)	Purchase by Telephone: Call (800) 441-7762 and speak with one of our representatives. The Fund has the right to reject any telephone request for any reason. Purchase in Writing: You may send a written request to BlackRock at the address on the back cover of this prospectus. Purchase by VRU: Investor A Shares may also be purchased by use of the Fund’s automated voice response unit (“VRU”) service at (800) 441-7762. Purchase by Internet: You may purchase your shares, and view activity in your account, by logging onto the BlackRock website at www.blackrock.com. Purchases made on the Internet using Automated Clearing House (“ACH”) will have a trade date that is the day after the purchase is made. Certain clients’ purchase orders of Institutional Shares placed by wire prior to the close of business on the NYSE will be priced at the net asset value determined that day. Contact your Financial Intermediary or BlackRock for further information. The Fund limits Internet purchases in shares of the Fund to $25,000 per trade. Different maximums may apply to certain institutional investors. Please read the On-Line Services Disclosure Statement and User Agreement, the Terms and Conditions page and the Consent to Electronic Delivery Agreement (if you consent to electronic delivery), before attempting to transact online. The Fund employs reasonable procedures to confirm that transactions entered over the Internet are genuine. By entering into the User Agreement with the Fund in order to open an account through the website, the shareholder waives any right to reclaim any losses from the Fund or any of its affiliates, incurred through fraudulent activity.
	Acquire additional shares by reinvesting dividends and capital gains	All dividends and capital gains distributions are automatically reinvested without a sales charge. To make any changes to your dividend and/or capital gains distributions options, please call (800) 441-7762, or contact your Financial Intermediary (if your account is not held directly with BlackRock).
	Participate in the AIP (Investor A and Institutional Shares only)	BlackRock’s AIP allows you to invest a specific amount on a periodic basis from your checking or savings account into your investment account. Refer to the “Account Services and Privileges” section of this prospectus for additional information.
How to Pay for Shares	Making payment for purchases (Investor A and Institutional Shares only)	Payment for an order must be made in Federal funds or other immediately available funds by the time specified by your Financial Intermediary, but in no event later than the close of the federal funds wire (normally 6:45 p.m. (Eastern time)). If payment is not received by this time, the order will be canceled and you and your Financial Intermediary will be responsible for any loss to the Fund. For shares purchased directly from the Fund, a check payable to BlackRock Funds which bears the name of the Fund must accompany a completed purchase application. There is a $20 fee for each purchase check that is returned due to insufficient funds. The Fund does not

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	Your Choices	Important Information For You to Know
How to Pay for Shares (continued)	Making payment for purchases (Investor A and Institutional Shares only) (continued)	accept third-party checks. You may also wire Federal funds to the Transfer Agent to purchase shares, but you must call (800) 441-7762 before doing so to confirm the wiring instructions.

How to Sell Shares

	Your Choices	Important Information For You to Know
Full or Partial Redemption of Shares	Have your Financial Intermediary submit your sales order	You can make redemption requests through your Financial Intermediary. Shareholders should indicate that they are redeeming Investor A, Investor C or Institutional Shares. The price of your shares is based on the next calculation of the Fund’s NAV after your order is placed. For your redemption request to be priced at the NAV on the day of your request, you must submit your request to your Financial Intermediary prior to that day’s close of business on the Exchange (generally 4:00 p.m. Eastern time). Certain Financial Intermediaries, however, may require submission of orders prior to that time. Any redemption request placed after that time will be priced at the NAV at the close of business on the next business day. Financial Intermediaries may charge a fee to process a redemption of shares. Shareholders should indicate which class of shares they are redeeming. The Fund may reject an order to sell shares under certain circumstances.
	Selling shares held directly with BlackRock	Methods of Redeeming Redeem by Telephone: You may redeem Investor Shares held at BlackRock by telephone request if certain conditions are met and if the amount being sold is less than (i) $100,000 for payments by check or (ii) $250,000 for payments through ACH or wire transfer. Certain redemption requests, such as those in excess of these amounts, must be in writing with a medallion signature guarantee. For Institutional Shares, certain redemption requests may require written instructions with a medallion signature guarantee. Call (800) 441-7762 for details. You can obtain a medallion signature guarantee stamp from a bank, securities dealer, securities broker, credit union, savings and loan association, national securities exchange or registered securities association. A notary public seal will not be acceptable. The Fund, its administrators and the Distributor will employ reasonable procedures to confirm that instructions communicated by telephone are genuine. The Fund and its service providers will not be liable for any loss, liability, cost or expense for acting upon telephone instructions that are reasonably believed to be genuine in accordance with such procedures. The Fund may refuse a telephone redemption request if it believes it is advisable to do so. During periods of substantial economic or market change, telephone redemptions may be difficult to complete. Please find below alternative redemption methods. Redeem by VRU: Investor Shares may also be redeemed by use of the Fund’s automated VRU service. Proceeds for Investor Shares redeemed by the VRU service may be paid for non-retirement accounts in amounts up to $25,000, either through check, ACH or wire. Redeem by Internet: You may redeem in your account, by logging onto the BlackRock website at www.blackrock.com. Proceeds from Internet redemptions may be sent via check, ACH or wire to the bank account of record. Proceeds for Investor Shares redeemed by Internet may be paid for non-retirement accounts in amounts up to $25,000, either through check, ACH or wire. Different maximums may apply to investors in Institutional Shares. Redeem in Writing: You may sell shares held at BlackRock by writing to BlackRock. All shareholders on the account must sign the letter. A medallion signature guarantee will generally be required but may be waived in certain limited circumstances. You can obtain a medallion

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	Your Choices	Important Information For You to Know
Full or Partial Redemption of Shares (continued)	Selling shares held directly with BlackRock (continued)	signature guarantee stamp from a bank, securities dealer, securities broker, credit union, savings and loan association, national securities exchange or registered securities association. A notary public seal will not be acceptable. If you hold stock certificates, return the certificates with the letter. Proceeds from redemptions may be sent via check, ACH or wire to the bank account of record. Payment of Redemption Proceeds Redemption proceeds may be paid by check or, if the Fund has verified banking information on file, through ACH or by wire transfer. Payment by Check: BlackRock will typically mail redemption proceeds one business day following receipt of a properly completed request, but in any event, within seven days. Shares can be redeemed by telephone and the proceeds sent by check to the shareholder at the address on record. Shareholders will pay $15 for redemption proceeds sent by check via overnight mail. You are responsible for any additional charges imposed by your bank for this service. The Fund reserves the right to reinvest any dividend or distribution amounts (e.g., income dividends or capital gains) which you have elected to receive by check should your check be returned as undeliverable or remain uncashed for more than 6 months. No interest will accrue on amounts represented by uncashed checks. Your check will be reinvested in your account at the NAV next calculated, on the day of the investment. When reinvested, those amounts are subject to the risk of loss like any fund investment. If you elect to receive distributions in cash and a check remains undeliverable or uncashed for more than 6 months, your cash election may also be changed automatically to reinvest and your future dividend and capital gains distributions will be reinvested in the Fund at the NAV as of the date of payment of the distribution. Payment by Wire Transfer: Proceeds for redeemed shares for which a redemption order is received before 4:00 p.m. (Eastern time) on a business day are normally paid in Federal funds wired to the redeeming shareholder on the next business day following redemption on which the Fund’s custodian is open for business. The Fund reserves the right to wire redemption proceeds within seven days after receiving a redemption order if, in the judgment of the Fund, an earlier payment could adversely affect the Fund. If a shareholder has given authorization for expedited redemption, shares can be redeemed by Federal wire transfer to a single previously designated bank account. Shareholders will pay $7.50 for redemption proceeds sent by Federal wire transfer. You are responsible for any additional charges imposed by your bank for this service. No charge for wiring redemption payments with respect to Institutional Shares is imposed by the Fund. The Fund is not responsible for the efficiency of the Federal wire system or the shareholder’s firm or bank. To change the name of the single, designated bank account to receive wire redemption proceeds, it is necessary to send a written request to the Fund at the address on the back cover of this prospectus. Payment by ACH: Redemption proceeds may be sent to the shareholder’s bank account (checking or savings) via ACH. Payment for redeemed shares for which a redemption order is received before 4:00 p.m. (Eastern time) on a business day is normally sent to the redeeming shareholder the next business day, with receipt at the receiving bank within the next two business days (48-72 hours), provided that the Fund’s custodian is also open for business. Payment for redemption orders received after 4:00 p.m. (Eastern time) or on a day when the Fund’s custodian is closed is normally sent on the next business day following redemption on which the Fund’s custodian is open for business.

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	Your Choices	Important Information For You to Know
Full or Partial Redemption of Shares (continued)	Selling shares held directly with BlackRock (continued)	The Fund reserves the right to send redemption proceeds within seven days after receiving a redemption order if, in the judgment of the Fund, an earlier payment could adversely affect the Fund. No charge for sending redemption payments via ACH is imposed by the Fund. *** If you make a redemption request before the Fund has collected payment for the purchase of shares, the Fund may delay mailing your proceeds. This delay will usually not exceed ten days. Under normal and stressed market conditions, the Fund typically expects to meet redemption requests by using cash or cash equivalents in its portfolio or by selling portfolio assets to generate additional cash.

How to Exchange Shares or Transfer Your Account

	Your Choices	Important Information For You to Know
Exchange Privilege	Selling shares of one BlackRock Fund to purchase shares of another BlackRock Fund (“exchanging”)	Investor or Institutional Shares of the Fund are generally exchangeable for shares of the same class of another BlackRock Fund, to the extent such shares are offered by your Financial Intermediary. You may exchange back into Investor A Shares of the original BlackRock Fund without incurring any sales charge or you may exchange into Investor A Shares of another BlackRock Fund and pay the difference, if any, between the sales charge previously paid and the sales charge payable at the time of the exchange into the new BlackRock Fund. You can exchange $1,000 or more of Investor Shares from one fund into the same class of another fund which offers that class of shares (you can exchange less than $1,000 of Investor Shares if you already have an account in the fund into which you are exchanging). Investors who currently own Institutional Shares of the Fund may make exchanges into Institutional Shares of other BlackRock Funds except for investors holding shares through certain client accounts at Financial Intermediaries that are omnibus with the Fund and do not meet applicable minimums. There is no required minimum amount with respect to exchanges of Institutional Shares. You may only exchange into a share class and fund that are open to new investors or in which you have a current account if the fund is closed to new investors. Some of the BlackRock Funds impose a sales charge. Therefore the exchange of Investor Shares may be subject to that sales charge. Exchanges of shares of the Fund for Investor Shares of another BlackRock Fund may be subject to the applicable CDSC upon the sale of these Investor Shares received in exchange. The CDSC will continue to be measured from the date of the original purchase. The CDSC schedule applicable to your original purchase will apply to the shares you receive in the exchange and any subsequent exchange. To exercise the exchange privilege, you may contact your Financial Intermediary. Alternatively, if your account is held directly with BlackRock, you may: (i) call (800) 441-7762 and speak with one of our representatives, (ii) make the exchange via the Internet by accessing your account online at www.blackrock.com, or (iii) send a written request to the Fund at the address on the back cover of this prospectus. Please note, if you indicated on your new account application that you did not want the Telephone Exchange Privilege, you will not be able to place exchanges via the telephone until you update this option either in writing or by calling (800) 441-7762. The Fund has the right to reject any telephone request for any reason. Although there is currently no limit on the number of exchanges that you can make, the exchange privilege may be modified or terminated at any time in the future. The Fund may suspend or terminate your exchange privilege at any time for any reason, including if the Fund believes, in its sole discretion, that you are engaging in market timing activities. See “Short-Term Trading Policy” below. For Federal income

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	Your Choices	Important Information For You to Know
Exchange Privilege (continued)	Selling shares of one BlackRock Fund to purchase shares of another BlackRock Fund (“exchanging”) (continued)	tax purposes a share exchange is a taxable event and a capital gain or loss may be realized. Please consult your tax adviser or other Financial Intermediary before making an exchange request.
Transfer Shares to Another Financial Intermediary	Transfer to a participating Financial Intermediary	You may transfer your shares of the Fund only to another securities dealer that has entered into an agreement with the Distributor. Certain shareholder services may not be available for the transferred shares. All future trading of these assets must be coordinated by the receiving firm. If your account is held directly with BlackRock, you may call (800) 441-7762 with any questions; otherwise please contact your Financial Intermediary to accomplish the transfer of shares.
	Transfer to a non-participating Financial Intermediary	You must either: • Transfer your shares to an account with the Fund; or • Sell your shares, paying any applicable deferred sales charge. If your account is held directly with BlackRock, you may call (800) 441-7762 with any questions; otherwise please contact your Financial Intermediary to accomplish the transfer of shares.

Account Services and Privileges

The following table provides examples of account services and privileges available in your BlackRock account. Certain of these account services and privileges are only available to shareholders of Investor Shares whose accounts are held directly with BlackRock. If your account is held directly with BlackRock, please call (800) 441-7762 or visit www.blackrock.com for additional information as well as forms and applications. Otherwise, please contact your Financial Intermediary for assistance in requesting one or more of the following services and privileges.

Automatic Investment Plan	Allows systematic investments on a periodic basis from your checking or savings account. (Investor A and Institutional Shares only)	BlackRock’s AIP allows you to invest a specific amount on a periodic basis from your checking or savings account into your investment account. You may apply for this option upon account opening or by completing the AIP application. The minimum investment amount for an automatic investment is $50 per portfolio.
Dividend Allocation Plan	Automatically invests your distributions into another BlackRock Fund of your choice pursuant to your instructions, without any fees or sales charges.	Dividend and capital gains distributions may be reinvested in your account to purchase additional shares or paid in cash. Using the Dividend Allocation Plan, you can direct your distributions to your bank account (checking or savings), to purchase shares of another fund at BlackRock without any fees or sales charges, or by check to a special payee. Please call (800) 441-7762 for details. If investing in another BlackRock Fund, the receiving fund must be open to new purchases.
EZ Trader	Allows an investor to purchase or sell Investor Shares by telephone or over the Internet through ACH.	(NOTE: This option is offered to shareholders whose accounts are held directly with BlackRock. Please speak with your Financial Intermediary if your account is held elsewhere.) Prior to establishing an EZ Trader account, please contact your bank to confirm that it is a member of the ACH system. Once confirmed, complete an application, making sure to include the appropriate bank information, and return the application to the address listed on the form. Prior to placing a telephone or Internet purchase or sale order, please call (800) 441-7762 to confirm that your bank information has been updated on your account. Once this is established, you may place your request to sell shares with the Fund by telephone or Internet. Proceeds will be sent to your pre-designated bank account.
Systematic Exchange Plan	This feature can be used by investors to systematically exchange money from one fund to up to four other funds.	A minimum of $10,000 in the initial BlackRock Fund is required, and investments in any additional funds must meet minimum initial investment requirements.

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Systematic Withdrawal Plan

This feature can be used by investors who want to receive regular distributions from their accounts.

To start a SWP, a shareholder must have a current investment of $10,000 or more in a BlackRock Fund.

Shareholders can elect to receive cash payments of $50 or more at any interval they choose. Shareholders may sign up by completing the SWP Application Form, which may be obtained from BlackRock. Shareholders should realize that if withdrawals exceed income the invested principal in their account will be depleted.

To participate in the SWP, shareholders must have their dividends reinvested. Shareholders may change or cancel the SWP at any time, with a minimum of 24 hours’ notice. If a shareholder purchases additional Investor A Shares of a fund at the same time he or she redeems shares through the SWP, that investor may lose money because of the sales charge involved. No CDSC will be assessed on redemptions of Investor A or Investor C Shares made through the SWP that do not exceed 12% of the account’s NAV on an annualized basis. For example, monthly, quarterly and semi-annual SWP redemptions of Investor A or Investor C Shares will not be subject to the CDSC if they do not exceed 1%, 3% and 6%, respectively, of an account’s NAV on the redemption date. SWP redemptions of Investor A or Investor C Shares in excess of this limit will still pay any applicable CDSC.

Ask your Financial Intermediary for details.

Fund’s Rights

The Fund may:

■	Suspend the right of redemption if trading is halted or restricted on the Exchange or under other emergency conditions described in the Investment Company Act;
■	Postpone the date of payment upon redemption if trading is halted or restricted on the Exchange or under other emergency conditions described in the Investment Company Act or if a redemption request is made before the Fund has collected payment for the purchase of shares;
■	Redeem shares for property other than cash as may be permitted under the Investment Company Act; and
■	Redeem shares involuntarily in certain cases, such as when the value of a shareholder account falls below a specified level.

Suspension of Redemptions Upon Liquidation. If the Board of Trustees of the Trust (the “Board”), including a majority of the trustees who are not “interested persons” of the Trust as defined in the Investment Company Act, determines either that (1) the Fund has invested, at the end of a business day, less than 10% of its total assets in weekly liquid assets, or (2) the Fund’s calculated NAV per share has deviated from $1.00 or such deviation is likely to occur; then the Board, subject to certain conditions, may, if it has determined to liquidate the Fund irrevocably, suspend redemptions and payment of redemption proceeds in order to facilitate the permanent liquidation of the Fund in an orderly manner. If this were to occur, it would likely result in a delay in your receipt of your redemption proceeds.

Note on Low Balance Accounts. Because of the high cost of maintaining smaller shareholder accounts, BlackRock has set a minimum balance of $500 in each Fund position you hold within your account (the “Fund Minimum”), and may redeem the shares in your account if the NAV of those shares in your account falls below $500 for any reason, including market fluctuation.

You will be notified that the value of your account is less than the Fund Minimum before the Fund makes any involuntary redemption. This notification will provide you with a 90 calendar day period to make an additional investment in order to bring the value of your account to at least $500 before the Fund makes an involuntary redemption. This involuntary redemption will not charge any deferred sales charge, and may not apply to accounts of certain employer-sponsored retirement plans (not including IRAs), qualified state tuition plan (529 Plan) accounts, and select fee-based programs at your Financial Intermediary.

Participation in Fee-Based Programs

If you participate in certain fee-based programs offered by BlackRock or an affiliate of BlackRock, or by Financial Intermediaries that have agreements with the Distributor or in certain fee-based programs in which BlackRock participates, you may be able to buy Institutional Shares, including by exchanges from other share classes. Sales

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charges on the shares being exchanged may be reduced or waived under certain circumstances. You generally cannot transfer shares held through a fee-based program into another account. Instead, if you choose to leave the fee-based program, you may have to redeem your shares held through the program and purchase shares of another class, which may be subject to distribution and service fees. This may be a taxable event and you may pay any applicable sales charges or redemption fee. Please speak to your Financial Intermediary for information about specific policies and procedures applicable to your account.

Generally, upon termination of a fee-based program, the shares may be liquidated, or the shares can be held in an account. In certain instances, when a shareholder chooses to continue to hold the shares, whatever share class was held in the program can be held after termination. Shares that have been held for less than specified periods within the program may be subject to a fee upon redemption. Shareholders that held Investor A or Institutional Shares in the program may be eligible to purchase additional shares of the respective share class of the Fund, but may be subject to upfront sales charges with respect to Investor A Shares. Additional purchases of Institutional Shares are permitted only if you have an existing position at the time of purchase or are otherwise eligible to purchase Institutional Shares. Please speak to your Financial Intermediary for more information.

Certain Financial Intermediaries may, in connection with a change in account type (for example, due to leaving a fee-based program or upon termination of the fee-based program) or otherwise in accordance with the Financial Intermediary’s policies and procedures, exchange the share class held in the program for another share class of the same fund, provided that the exchanged shares are not subject to a sales charge and the shareholder meets the eligibility requirements of the new share class. Please speak to your Financial Intermediary for information about specific policies and procedures applicable to your account.

Details about the features of each fee-based program and the relevant charges, terms and conditions are included in the client agreement for each fee-based program and are available from your Financial Intermediary. Please speak to your Financial Intermediary for more information.

Short-Term Trading Policy

Market timing is an investment technique involving frequent short-term trading of mutual fund shares designed to exploit market movements or inefficiencies in the way a mutual fund prices its shares. The Board has evaluated the risks of market timing activities by the Fund’s shareholders and has determined that due to (i) the Fund’s policy of seeking to maintain the Fund’s NAV per share at $1.00 each day, (ii) the nature of the Fund’s portfolio holdings, and (iii) the nature of the Fund’s shareholders, it is unlikely that (a) market timing would be attempted by the Fund’s shareholders or (b) any attempts to market time the Fund by shareholders would result in a negative impact to the Fund or its shareholders. As a result, the Board has not adopted policies and procedures to deter short-term trading in the Fund. There can be no assurances, however, that the Fund may not, on occasion, serve as a temporary or short-term investment vehicle for those who seek to market time funds offered by other investment companies.

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Management of the Fund

BlackRock

BlackRock is the Fund’s manager and manages the Fund’s investments and its business operations subject to the oversight of the Board. While BlackRock is ultimately responsible for the management of the Fund, it is able to draw upon the research and expertise of its asset management affiliates for portfolio decisions and management with respect to certain portfolio securities. BlackRock is an indirect, wholly-owned subsidiary of BlackRock, Inc.

BlackRock, a registered investment adviser, was organized in 1994 to perform advisory services for investment companies. BlackRock and its affiliates had approximately $9.425 trillion in investment company and other portfolio assets under management as of June 30, 2023.

BlackRock serves as manager to the Fund pursuant to a management agreement (the “Management Agreement”) between BlackRock and the Trust, on behalf of the Fund, which provides that BlackRock is to be paid fees computed daily and payable monthly at the maximum annual management fee rate of 0.50% of the Fund’s average daily net assets.

BlackRock has contractually agreed to cap net expenses (excluding: (i) interest, taxes, dividends tied to short sales, brokerage commissions, and other expenditures which are capitalized in accordance with generally accepted accounting principles; (ii) the Fund’s pro rata share of the fees and expenses incurred indirectly by the Fund as a result of investing in other investment companies; (iii) other expenses attributable to, and incurred as a result of, the Fund’s investments; and (iv) extraordinary expenses (including litigation expenses) not incurred in the ordinary course of the Fund’s business, if any) of each share class of the Fund at the levels shown below and in the Fund’s fees and expenses table in the “Fund Overview” section of this prospectus. Items (i), (ii), (iii) and (iv) in the preceding sentence are referred to in this prospectus as “Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses.” To achieve these expense caps, BlackRock has agreed to waive and/or reimburse fees or expenses if these operating expenses exceed a certain limit.

With respect to the Fund, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses to the amounts noted in the table below.

	Contractual Caps¹ on Total Annual Fund Operating Expenses² (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses)	Total Annual Fund Operating Expenses² after giving effect to all applicable expense limitation provisions (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund Expenses)
Investor A	0.42%	0.41%
Investor C	1.17%	1.11%
Institutional	0.42%	0.41%

¹	The contractual caps are in effect through June 30, 2025. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.
²	As a percentage of average daily net assets.

BlackRock and the Distributor have voluntarily agreed to waive a portion of their respective fees and/or reimburse operating expenses to enable the Fund to maintain minimum levels of daily net investment income. BlackRock and the Distributor may discontinue this waiver and/or reimbursement at any time without notice.

For the fiscal year ended April 30, 2023, BlackRock received a management fee, net of any applicable waivers and/or reimbursements, at the annual rate of 0.35% of the Fund’s average daily net assets.

A discussion of the basis for the Board’s approval of the Management Agreement with BlackRock is included in the Fund’s semi-annual shareholder report for the fiscal period ended October 31, 2022.

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From time to time, a manager, analyst, or other employee of BlackRock or its affiliates may express views regarding a particular asset class, company, security, industry, or market sector. The views expressed by any such person are the views of only that individual as of the time expressed and do not necessarily represent the views of BlackRock or any other person within the BlackRock organization. Any such views are subject to change at any time based upon market or other conditions and BlackRock disclaims any responsibility to update such views. These views may not be relied on as investment advice and, because investment decisions for the Fund are based on numerous factors, may not be relied on as an indication of trading intent on behalf of the Fund.

Conflicts of Interest

The investment activities of BlackRock and its affiliates (including BlackRock, Inc. and its subsidiaries (collectively, the “Affiliates”)), and their respective directors, officers or employees, in the management of, or their interest in, their own accounts and other accounts they manage, may present conflicts of interest that could disadvantage the Fund and its shareholders.

BlackRock and its Affiliates provide investment management services to other funds and discretionary managed accounts that may follow investment programs similar to that of the Fund. BlackRock and its Affiliates are involved worldwide with a broad spectrum of financial services and asset management activities and may engage in the ordinary course of business in activities in which their interests or the interests of their clients may conflict with those of the Fund. BlackRock or one or more Affiliates act or may act as an investor, research provider, investment manager, commodity pool operator, commodity trading advisor, financier, underwriter, adviser, trader, lender, index provider, agent and/or principal, and have other direct and indirect interests in securities, currencies, commodities, derivatives and other instruments in which the Fund may directly or indirectly invest. The Fund may invest in securities of, or engage in other transactions with, companies with which an Affiliate has significant debt or equity investments or other interests. The Fund may also invest in issuances (such as structured notes) by entities for which an Affiliate provides and is compensated for cash management services relating to the proceeds from the sale of such issuances. The Fund also may invest in securities of, or engage in other transactions with, companies for which an Affiliate provides or may in the future provide research coverage. An Affiliate may have business relationships with, and purchase, or distribute or sell services or products from or to, distributors, consultants or others who recommend the Fund or who engage in transactions with or for the Fund, and may receive compensation for such services. BlackRock or one or more Affiliates may engage in proprietary trading and advise accounts and funds that have investment objectives similar to those of the Fund and/or that engage in and compete for transactions in the same types of securities, currencies and other instruments as the Fund. This may include transactions in securities issued by other open-end and closed-end investment companies (which may include investment companies that are affiliated with the Fund and BlackRock, to the extent permitted under the Investment Company Act). The trading activities of BlackRock and these Affiliates are carried out without reference to positions held directly or indirectly by the Fund and may result in BlackRock or an Affiliate having positions in certain securities that are senior or junior to, or have interests different from or adverse to, the securities that are owned by the Fund.

Neither BlackRock nor any Affiliate is under any obligation to share any investment opportunity, idea or strategy with the Fund. As a result, an Affiliate may compete with the Fund for appropriate investment opportunities. The results of the Fund’s investment activities, therefore, may differ from those of an Affiliate and of other accounts managed by BlackRock or an Affiliate, and it is possible that the Fund could sustain losses during periods in which one or more Affiliates and other accounts achieve profits on their trading for proprietary or other accounts. The opposite result is also possible.

In addition, the Fund may, from time to time, enter into transactions in which BlackRock or an Affiliate or their directors, officers or employees or other clients have an adverse interest. Furthermore, transactions undertaken by clients advised or managed by BlackRock or its Affiliates may adversely impact the Fund. Transactions by one or more clients or BlackRock or its Affiliates or their directors, officers or employees, may have the effect of diluting or otherwise disadvantaging the values, prices or investment strategies of the Fund. The Fund’s activities may be limited because of regulatory restrictions applicable to BlackRock or one or more Affiliates and/or their internal policies designed to comply with such restrictions.

Under a securities lending program approved by the Board, the Trust, on behalf of the Fund, has retained BlackRock Investment Management, LLC, an Affiliate of BlackRock, to serve as the securities lending agent for the Fund to the extent that the Fund participates in the securities lending program. For these services, the securities lending agent will receive a fee from the Fund, including a fee based on the returns earned on the Fund’s investment of the cash received as collateral for the loaned securities. In addition, one or more Affiliates may be among the entities to which the Fund may lend its portfolio securities under the securities lending program.

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The activities of BlackRock and its Affiliates and their respective directors, officers or employees, may give rise to other conflicts of interest that could disadvantage the Fund and its shareholders. BlackRock has adopted policies and procedures designed to address these potential conflicts of interest. See the SAI for further information.

Valuation of Fund Investments

When you buy shares, you pay the net asset value (normally $1.00 per share) without a sales charge. This is the offering price. Shares are also redeemed at their net asset value, minus any applicable deferred sales charge. The Fund calculates the net asset value each day the Exchange is open as of the close of business on the Exchange, based on prices at the time of closing. The Exchange generally closes at 4:00 p.m. Eastern time. The Exchange is closed on New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Juneteenth, Independence Day, Labor Day, Thanksgiving Day and Christmas Day. The net asset value used in determining your share price is the next one calculated after your purchase or redemption order becomes effective. Share purchase orders are effective on the date Federal funds become available to the Fund.

The amortized cost method is used in calculating net asset value, meaning that the calculation is based on a valuation of the assets held by the Fund at cost, with an adjustment for any discount or premium on a security at the time of purchase. Generally, trading in foreign securities, U.S. Government securities, money market instruments, and certain fixed-income securities is substantially completed each day at various times prior to the close of business on the Exchange. The values of such securities used in computing the net asset value of the Fund’s shares are determined as of such times.

The Fund may accept orders from certain authorized Financial Intermediaries or their designees. The Fund will be deemed to receive an order when accepted by the Financial Intermediary or designee, and the order will receive the net asset value next computed by the Fund after such acceptance. If the payment for a purchase order is not made by a designated later time, the order will be canceled and the Financial Intermediary could be held liable for any losses.

Dividends, Distributions and Taxes

The Fund will distribute net investment income, if any, monthly and net realized capital gains, if any, at least annually. Net investment income dividends are declared daily and reinvested monthly and capital gain dividends are reinvested at least annually in the form of additional shares at net asset value without a sales charge. You will begin accruing dividends on the day following the date your purchase becomes effective. Dividends that are declared but unpaid will remain in the gross assets of the Fund and will, therefore, continue to earn income for the Fund’s shareholders. In most cases, shareholders will receive statements monthly or quarterly as to such reinvestments. Shareholders redeeming their holdings will receive all dividends declared through the date of redemption. Although this cannot be predicted with any certainty, the Fund anticipates that a significant amount of its dividends, if any, will consist of ordinary income. Capital gains may be taxable to you at different rates depending on how long the Fund held the assets sold.

You will pay tax on dividends from the Fund whether you receive them in cash or additional shares. If you redeem Fund shares or exchange them for shares of another fund, you generally will be treated as having sold your shares and any gain on the transaction may be subject to tax. Fund distributions derived from qualified dividend income, which consists of dividends received from U.S. corporations and qualifying foreign corporations, and from long-term capital gains are eligible for taxation at a maximum rate of 15% or 20% for individuals, depending on whether their income exceeds certain threshold amounts, which are adjusted annually for inflation.

A 3.8% Medicare tax is imposed on the net investment income (which includes, but is not limited to, interest, dividends and net gain from investments) of U.S. individuals with income exceeding $200,000, or $250,000 if married filing jointly, and of trusts and estates.

Your dividends and redemption proceeds will be subject to backup withholding tax if you have not provided a taxpayer identification number or social security number or the number you have provided is incorrect.

If you are neither a tax resident nor a citizen of the United States or if you are a foreign entity (other than a pass-through entity to the extent owned by U.S. persons), the Fund’s ordinary income dividends will generally be subject to a 30% U.S. withholding tax, unless a lower treaty rate applies. However, certain distributions reported by the Fund as capital gain dividends, interest-related dividends or short-term capital gain dividends and paid to a foreign shareholder may be eligible for an exemption from U.S. withholding tax.

Separately, a 30% withholding tax is currently imposed on U.S.-source dividends, interest and other income items paid to (i) certain foreign financial institutions and investment funds, and (ii) certain other foreign entities. To avoid

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Financial Highlights

The Financial Highlights tables are intended to help you understand the Fund’s financial performance for the periods shown. Certain information reflects the financial 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/or distributions). The information has been audited by Deloitte & Touche, LLP, whose report, along with the Fund’s audited financial statements, is included in the Fund’s Annual Report, which is available upon request.

	BlackRock Summit Cash Reserves Fund
	Institutional
	Year Ended 04/30/23	Year Ended 04/30/22	Year Ended 04/30/21	Period from 07/15/19^(a) to 04/30/20
(For a share outstanding throughout each period)	Year Ended 04/30/23	Year Ended 04/30/22	Year Ended 04/30/21	Period from 07/15/19^(a) to 04/30/20
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Net investment income	0.0263	0.0001	0.0000^(b)	0.0098
Net realized and unrealized gain	0.0000^(b)	0.0000^(b)	0.0003	0.0000^(b)
Net increase from investment operations	0.0263	0.0001	0.0003	0.0098
Distributions^(c)
From net investment income	(0.0263)	(0.0001)	(0.0000)^(d)	(0.0098)
From net realized gain	(0.0000)^(d)	(0.0000)^(d)	(0.0003)	(0.0000)^(d)
Total distributions	(0.0263)	(0.0001)	(0.0003)	(0.0098)
Net asset value, end of period	$1.00	$1.00	$1.00	$1.00
Total Return^(e)
Based on net asset value	2.66%	0.01%	0.03%	0.98%^(f)
Ratios to Average Net Assets
Total expenses	0.59%	0.60%	0.61%	0.64%^(g)(h)
Total expenses after fees waived and/or reimbursed	0.41%	0.12%	0.17%	0.42%^(g)(h)
Net investment income	2.66%	0.00%⁽ⁱ⁾	0.00%⁽ⁱ⁾	1.20%^(h)
Supplemental Data
Net assets, end of period (000)	$97,307	$101,901	$87,699	$97,718

^(a)	Commencement of operations.
^(b)	Amount is less than $0.00005 per share.
^(c)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(d)	Amount is greater than $(0.00005) per share.
^(e)	Where applicable, assumes the reinvestment of distributions.
^(f)	Not annualized.
^(g)	Includes non-recurring expenses of offering, organization and reorganization costs. Without these costs, total expenses and total expenses after fees waived and/or reimbursed would have been 0.62% and 0.39% for the period ended 04/30/2020, respectively.
^(h)	Annualized.
⁽ⁱ⁾	Amount is less than 0.005%.

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Financial Highlights (continued)

	BlackRock Summit Cash Reserves Fund
	Investor A
	Year Ended 04/30/23	Year Ended 04/30/22	Year Ended 04/30/21	Year Ended 04/30/20	Year Ended 04/30/19
(For a share outstanding throughout each period)	Year Ended 04/30/23	Year Ended 04/30/22	Year Ended 04/30/21	Year Ended 04/30/20	Year Ended 04/30/19
Net asset value, beginning of year	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Net investment income	0.0263	0.0002	0.0000^(a)	0.0142	0.0135
Net realized and unrealized gain	0.0000^(a)	0.0000^(a)	0.0003	0.0000^(a)	0.0000^(a)
Net increase from investment operations	0.0263	0.0002	0.0003	0.0142	0.0135
Distributions^(b)
From net investment income	(0.0263)	(0.0002)	(0.0000)^(c)	(0.0142)	(0.0135)
From net realized gain	(0.0000)^(c)	(0.0000)^(c)	(0.0003)	(0.0000)^(c)	(0.0000)^(c)
Total distributions	(0.0263)	(0.0002)	(0.0003)	(0.0142)	(0.0135)
Net asset value, end of year	$1.00	$1.00	$1.00	$1.00	$1.00
Total Return^(d)
Based on net asset value	2.66%	0.02%	0.04%	1.43%	1.35%
Ratios to Average Net Assets
Total expenses	0.59%	0.61%	0.60%	0.64%^(e)	0.82%^(e)
Total expenses after fees waived and/or reimbursed	0.41%	0.10%	0.17%	0.42%^(e)	0.52%^(e)
Net investment income	2.74%	0.01%	0.00%^(f)	1.36%	1.86%
Supplemental Data
Net assets, end of year (000)	$484,690	$356,419	$346,281	$405,760	$319,960

^(a)	Amount is less than $0.00005 per share.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Amount is greater than $(0.00005) per share.
^(d)	Where applicable, assumes the reinvestment of distributions.
^(e)	Includes non-recurring expenses of offering, organization and reorganization costs. Without these costs, total expenses and total expenses after fees waived and/or reimbursed would have been 0.61% and 0.40% for the year ended 04/30/20, respectively, and 0.72% and 0.42% for the year ended 04/30/19, respectively.
^(f)	Amount is less than 0.005%.

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Financial Highlights (concluded)

	BlackRock Summit Cash Reserves Fund
	Investor C
	Year Ended 04/30/23	Year Ended 04/30/22	Year Ended 04/30/21	Year Ended 04/30/20	Period from 08/10/18^(a) to 04/30/19
(For a share outstanding throughout each period)	Year Ended 04/30/23	Year Ended 04/30/22	Year Ended 04/30/21	Year Ended 04/30/20	Period from 08/10/18^(a) to 04/30/19
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Net investment income	0.0194	0.0002	0.0000^(b)	0.0075	0.0058
Net realized and unrealized gain	0.0000^(b)	0.0000^(b)	0.0003	0.0000^(b)	0.0000^(b)
Net increase from investment operations	0.0194	0.0002	0.0003	0.0075	0.0058
Distributions^(c)
From net investment income	(0.0194)	(0.0002)	(0.0000)^(d)	(0.0075)	(0.0058)
From net realized gain	(0.0000)^(d)	(0.0000)^(d)	(0.0003)	(0.0000)^(d)	(0.0000)^(d)
Total distributions	(0.0194)	(0.0002)	(0.0003)	(0.0075)	(0.0058)
Net asset value, end of period	$1.00	$1.00	$1.00	$1.00	$1.00
Total Return^(e)
Based on net asset value	1.96%	0.03%	0.04%	0.75%	0.58%^(f)
Ratios to Average Net Assets
Total expenses	1.35%	1.46%	1.38%	1.52%^(g)	1.47%^(g)(h)
Total expenses after fees waived and/or reimbursed	1.11%	0.10%	0.20%	0.90%^(g)	1.20%^(g)(h)
Net investment income	1.75%	0.02%	0.00%⁽ⁱ⁾	0.51%	1.25%^(h)
Supplemental Data
Net assets, end of period (000)	$820	$948	$1,052	$1,956	$651

^(a)	Commencement of operations.
^(b)	Amount is less than $0.00005 per share.
^(c)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(d)	Amount is greater than $(0.00005) per share.
^(e)	Where applicable, excludes the effects of any sales charges and assumes the reinvestment of distributions.
^(f)	Not annualized.
^(g)	Includes non-recurring expenses of offering, organization and reorganization costs. Without these costs, total expenses and total expenses after fees waived and/or reimbursed would have been 1.49% and 0.87% for the year ended 04/30/20, respectively, and 1.38% and 1.11% for the period ended 04/30/19, respectively.
^(h)	Annualized.
⁽ⁱ⁾	Amount is less than 0.005%.

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General Information

Shareholder Documents

Electronic Access to Annual Reports, Semi-Annual Reports and Prospectuses

Electronic copies of most financial reports and prospectuses are available at www.blackrock.com/cash/regulatory. Shareholders can sign up for e-mail notifications of annual and semi-annual reports and prospectuses by enrolling in the Fund’s electronic delivery program. To enroll:

Shareholders Who Hold Accounts with Investment Advisers, Banks or Brokerages: Please contact your Financial Intermediary. Please note that not all investment advisers, banks or brokerages may offer this service.

Shareholders Who Hold Accounts Directly With BlackRock:

■	Access the BlackRock website at http://www.blackrock.com/edelivery; and
■	Log into your account.

Delivery of Shareholder Documents

The Fund delivers only one copy of shareholder documents, including prospectuses, shareholder reports and proxy statements, to shareholders with multiple accounts at the same address. This practice is known as “householding” and is intended to eliminate duplicate mailings and reduce expenses. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please contact the Fund at (800) 441-7762.

Certain Fund Policies

Anti-Money Laundering Requirements

The Fund is subject to the USA PATRIOT Act (the “Patriot Act”). The Patriot Act is intended to prevent the use of the U.S. financial system in furtherance of money laundering, terrorism or other illicit activities. Pursuant to requirements under the Patriot Act, the Fund is required to obtain sufficient information from shareholders to enable it to form a reasonable belief that it knows the true identity of its shareholders. This information will be used to verify the identity of investors or, in some cases, the status of Financial Intermediaries. Such information may be verified using third-party sources. This information will be used only for compliance with the Patriot Act or other applicable laws, regulations and rules in connection with money laundering, terrorism or economic sanctions.

The Fund reserves the right to reject purchase orders from persons who have not submitted information sufficient to allow the Fund to verify their identity. The Fund also reserves the right to redeem any amounts in the Fund from persons whose identity it is unable to verify on a timely basis. It is the Fund’s policy to cooperate fully with appropriate regulators in any investigations conducted with respect to potential money laundering, terrorism or other illicit activities.

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your Financial Intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our website.

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BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law, or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Statement of Additional Information

If you would like further information about the Fund, including how it invests, please see the SAI.

For a discussion of the Fund’s policies and procedures regarding the selective disclosure of its portfolio holdings, please see the SAI.

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Glossary

This glossary contains an explanation of some of the common terms used in this prospectus. For additional information about the Fund, please see the SAI.

Annual Fund Operating Expenses — expenses that cover the costs of operating the Fund.

Daily Liquid Assets — include (i) cash; (ii) direct obligations of the U.S. Government; (iii) securities that will mature, as determined without reference to the maturity shortening provisions of Rule 2a-7 regarding interest rate readjustments, or are subject to a demand feature that is exercisable and payable within one business day; and (iv) amounts receivable and due unconditionally within one business day on pending sales of portfolio securities.

Distribution Fees — fees used to support the Fund’s marketing and distribution efforts, such as compensating Financial Intermediaries, advertising and promotion.

Dollar-Weighted Average Life — the dollar-weighted average maturity of the Fund’s portfolio calculated without reference to the exceptions used for variable or floating rate securities regarding the use of interest rate reset dates in lieu of the security’s actual maturity date. “Dollar-weighted” means the larger the dollar value of a debt security in the Fund, the more weight it gets in calculating this average.

Dollar-Weighted Average Maturity — average maturity of the Fund is the average amount of time until the organizations that issued the debt securities in the Fund’s portfolio must pay off the principal amount of the debt. “Dollar-weighted” means the larger the dollar value of a debt security in the Fund, the more weight it gets in calculating this average. To calculate the dollar-weighted average maturity, the Fund may treat a variable or floating rate security as having a maturity equal to the time remaining to the security’s next interest rate reset date rather than the security’s actual maturity.

Management Fee — a fee paid to BlackRock for managing the Fund.

Other Expenses — include transfer agency, custody, professional and registration fees.

Service Fees — fees used to compensate Financial Intermediaries for certain shareholder servicing activities.

Shareholder Fees — fees paid directly by a shareholder, including sales charges that you may pay when you buy or sell shares of the Fund.

Weekly Liquid Assets — include (i) cash; (ii) direct obligations of the U.S. Government; (iii) U.S. Government securities issued by a person controlled or supervised by and acting as an instrumentality of the U.S. Government pursuant to authority granted by the U.S. Congress, that are issued at a discount to the principal amount to be repaid at maturity without provision for the payment of interest and have a remaining maturity of 60 days or less; (iv) securities that will mature, as determined without reference to the maturity shortening provisions of Rule 2a-7 regarding interest rate readjustments, or are subject to a demand feature that is exercisable and payable within five business days; and (v) amounts receivable and due unconditionally within five business days on pending sales of portfolio securities.

Yield — the income generated by an investment in the Fund.

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Intermediary-Defined Sales Charge Waiver Policies

Ameriprise Financial:

Investor A Shares Front-End Sales Charge Waivers Available at Ameriprise Financial:

The following information applies to Investor A Shares purchases if you have an account with or otherwise purchase Fund shares through Ameriprise Financial:

Shareholders purchasing Fund shares through an Ameriprise Financial retail brokerage account are eligible for the following front-end sales charge waivers, which may differ from those disclosed elsewhere in this Fund’s prospectus or SAI:

■	Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs or SAR-SEPs.
■	Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same Fund (but not any other fund within BlackRock Funds).
■	Shares exchanged from Investor C Shares of the same fund in the month of or following the 7-year anniversary of the purchase date. To the extent that this prospectus elsewhere provides for a waiver with respect to exchanges of Investor C Shares or conversion of Investor C Shares following a shorter holding period, that waiver will apply.
■	Employees and registered representatives of Ameriprise Financial or its affiliates and their immediate family members.
■	Shares purchased by or through qualified accounts (including IRAs, Coverdell Education Savings Accounts, 401(k)s, 403(b) TSCAs subject to ERISA and defined benefit plans) that are held by a covered family member, defined as an Ameriprise financial advisor and/or the advisor’s spouse, advisor’s lineal ascendant (mother, father, grandmother, grandfather, great grandmother, great grandfather), advisor’s lineal descendant (son, step-son, daughter, step-daughter, grandson, granddaughter, great grandson, great granddaughter) or any spouse of a covered family member who is a lineal descendant.
■	Shares purchased from the proceeds of redemptions within BlackRock Funds, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (i.e. Rights of Reinstatement).

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D.A. Davidson & Co. (“D.A. Davidson”):

Effective March 1, 2021, shareholders purchasing Fund shares including existing Fund shareholders, through a D.A. Davidson platform or account, or through an introducing broker-dealer or independent registered investment advisor for which D.A. Davidson provides trade execution, clearance, and/or custody services, will be eligible for the following sales charge waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this Prospectus or the Fund’s SAI.

Front-End Sales Charge Waivers on Investor A Shares Available at D.A. Davidson

■	Shares purchased of the same Fund or another BlackRock Fund through a systematic reinvestment of capital gains and dividend distributions.
■	Shares purchased by employees and registered representatives of D.A. Davidson or its affiliates and their family members as designated by D.A. Davidson.
■	Shares purchased from the proceeds of redemptions of the same Fund or another BlackRock Fund, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement).
■	A shareholder in the Fund’s Investor C Shares will have their shares converted at net asset value to Investor A Shares (or the appropriate share class) of the Fund if the shares are no longer subject to a CDSC and the conversion is consistent with D.A. Davidson’s policies and procedures.

CDSC Waivers on Investor A and C Shares Available at D.A. Davidson

■	Shares sold due to the death or disability of the shareholder.
■	Shares sold as part of a systematic withdrawal plan as described in the Fund’s prospectus.
■	Shares bought due to return of excess contributions from an IRA account.
■	Shares sold as part of a required minimum distribution for IRA or other qualifying retirement accounts pursuant to the Internal Revenue Code.
■	Shares acquired through a Right of Reinstatement.

Front-End Sales Charge Discounts Available at D.A. Davidson: Breakpoints, Rights of Accumulation and/or Letters of Intent

■	Breakpoints as described in this Prospectus.
■	Rights of accumulation which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of BlackRock Fund assets held by accounts within the purchaser’s household at D.A. Davidson. Eligible BlackRock Fund assets not held at D.A. Davidson may be included in the calculation of rights of accumulation only if the shareholder notifies his or her financial advisor about such assets.
■	Letters of intent which allow for breakpoint discounts based on anticipated purchases of BlackRock Funds, over a 13-month time period. Eligible BlackRock Fund assets not held at D.A. Davidson may be included in the calculation of letters of intent only if the shareholder notifies his or her financial advisor about such assets.

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Edward D. Jones & Co., L.P. (“Edward Jones”):

Policies Regarding Transactions Through Edward Jones

The following information has been provided by Edward Jones:

Effective on or after January 15, 2021, the following information supersedes prior information with respect to transactions and positions held in fund shares through an Edward Jones system. Clients of Edward Jones (also referred to as “shareholders”) purchasing fund shares on the Edward Jones commission and fee-based platforms are eligible only for the following sales charge discounts (also referred to as “breakpoints”) and waivers, which may differ from discounts and waivers described elsewhere in this prospectus or statement of additional information (“SAI”) or through another broker-dealer. In all instances, it is the shareholder’s responsibility to inform Edward Jones at the time of purchase of any relationship, holdings of BlackRock Funds, or other facts qualifying the purchaser for discounts or waivers. Edward Jones can ask for documentation of such circumstance. Shareholders should contact Edward Jones if they have questions regarding their eligibility for these discounts and waivers.

Breakpoints

■	Breakpoint pricing, otherwise known as volume pricing, at dollar thresholds as described in the prospectus.

Rights of Accumulation (“ROA”)

■	The applicable sales charge on a purchase of Investor A Shares is determined by taking into account all share classes (except certain money market funds and any assets held in group retirement plans) of BlackRock Funds held by the shareholder or in an account grouped by Edward Jones with other accounts for the purpose of providing certain pricing considerations (“pricing groups”). If grouping assets as a shareholder, this includes all share classes held on the Edward Jones platform and/or held on another platform. The inclusion of eligible fund family assets in the ROA calculation is dependent on the shareholder notifying Edward Jones of such assets at the time of calculation. Money market funds are included only if such shares were sold with a sales charge at the time of purchase or acquired in exchange for shares purchased with a sales charge.
■	The employer maintaining a SEP IRA plan and/or SIMPLE IRA plan may elect to establish or change ROA for the IRA accounts associated with the plan to a plan-level grouping as opposed to including all share classes at a shareholder or pricing group level.
■	ROA is determined by calculating the higher of cost minus redemptions or market value (current shares multiplied by NAV).

Letter of Intent (“LOI”)

■

Through a LOI, a shareholder can receive the sales charge and breakpoint discounts for purchases such shareholder intends to make over a 13-month period from the date Edward Jones receives the LOI. The LOI is determined by calculating the higher of cost or market value of qualifying holdings at LOI initiation in combination with the value that the shareholder intends to buy over a 13-month period to calculate the front-end sales charge and any breakpoint discounts. Each purchase the shareholder makes during that 13-month period will receive the sales charge and breakpoint discount that applies to the total amount. The inclusion of eligible BlackRock Funds assets in the LOI calculation is dependent on the shareholder notifying Edward Jones of such assets at the time of calculation. Purchases made before the LOI is received by Edward Jones are not adjusted under the LOI and will not reduce the sales charges previously paid. Sales charges will be adjusted if the LOI is not met.

■

If the employer maintaining a SEP IRA plan and/or SIMPLE IRA plan has elected to establish or change ROA for the IRA accounts associated with the plan to a plan-level grouping, LOIs will also be at the plan-level and may only be established by the employer.

Sales Charge Waivers

Sales charges are waived for the following shareholders and in the following situations:

■	Associates of Edward Jones and its affiliates and their family members who are in the same pricing group (as determined by Edward Jones under its policies and procedures) as the associate. This waiver will continue for the remainder of the associate’s life if the associate retires from Edward Jones in good-standing and remains in good standing pursuant to Edward Jones’ policies and procedures.
■	Shares purchased in an Edward Jones fee-based advisory program.
■	Shares purchased through reinvestment of capital gains distributions and dividend reinvestment.
■	Shares purchased from the proceeds of redeemed shares of BlackRock Funds so long as the following conditions are met: 1) the proceeds are from the sale of shares within 60 days of the purchase, and 2) the sale and purchase

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	are made in the same share class and the same account or the purchase is made in an individual retirement account (“IRA”) with proceeds from liquidations in a non-retirement account.
■	Shares exchanged into Investor A Shares from another share class so long as the exchange is into the same fund and was initiated at the discretion of Edward Jones. Edward Jones is responsible for any remaining CDSCs due to BlackRock, if applicable. Any future purchases are subject to the applicable sales charge as disclosed in the prospectus.
■	Exchanges from Investor C Shares to Investor A Shares of the same fund, generally, in the 84th month following the anniversary of the purchase date or earlier at the discretion of Edward Jones.

Contingent Deferred Sales Charge (“CDSC”) Waivers

If the shareholder purchases shares that are subject to a CDSC and those shares are redeemed before the CDSC is expired, the shareholder is responsible to pay the CDSC except in the following conditions:

■	The death or disability of the shareholder.
■	Systematic withdrawals with up to 10% per year of the account value.
■	Return of excess contributions from an IRA.
■	Shares sold as part of a required minimum distribution for IRA and retirement accounts if the redemption is taken in or after the year the shareholder reaches qualified age based on applicable IRS regulations.
■	Shares sold to pay Edward Jones fees or costs in such cases where the transaction is initiated by Edward Jones.
■	Shares exchanged in an Edward Jones fee-based program.
■	Shares acquired through a Right of Reinstatement.
■	Shares redeemed at the discretion of Edward Jones for Minimum Balances, as described below.

Other Important Information Regarding Transactions Through Edward Jones

Minimum Purchase Amounts for Investor A and Investor C Shares

■	Initial purchase minimum: $250
■	Subsequent purchase minimum: none

Minimum Balances

■	Edward Jones has the right to redeem at its discretion fund holdings with a balance of $250 or less. The following are examples of accounts that are not included in this policy:

■	A fee-based account held on an Edward Jones platform
■	A 529 account held on an Edward Jones platform
■	An account with an active systematic investment plan or LOI

Exchanging Share Classes

■

At any time it deems necessary, Edward Jones has the authority to exchange at NAV a shareholder’s holdings in a fund to Investor A Shares of the same fund at NAV, provided that Edward Jones will be responsible for any remaining CDSC due to BlackRock, if applicable, and that the shareholders meet the eligibility requirements of the new share class.

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Janney Montgomery Scott LLC:

Effective May 1, 2020, if you purchase fund shares through a Janney Montgomery Scott LLC (“Janney”) brokerage account, you will be eligible for the following sales charge waivers (front-end sales charge waivers and contingent deferred sales charge (“CDSC”), or back-end sales charge, waivers) and discounts, which may differ from those disclosed elsewhere in this Fund’s prospectus or SAI.

Front-end sales charge* waivers on Investor A shares available at Janney

■	Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other BlackRock Fund).
■	Shares purchased by employees and registered representatives of Janney or its affiliates and their family members as designated by Janney.
■	Shares purchased from the proceeds of redemptions from another BlackRock Fund, provided (1) the repurchase occurs within ninety (90) days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (i.e., right of reinstatement).
■	Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans.
■	Shares acquired through a right of reinstatement.
■	Investor C shares that are no longer subject to a contingent deferred sales charge and are converted to Investor A shares of the same fund pursuant to Janney’s policies and procedures.

CDSC waivers on Investor A and C shares available at Janney

■	Shares sold upon the death or disability of the shareholder.
■	Shares sold as part of a systematic withdrawal plan as described in the Fund’s prospectus or SAI.
■	Shares purchased in connection with a return of excess contributions from an IRA account.
■	Shares sold as part of a required minimum distribution for IRA and retirement accounts pursuant to the Internal Revenue Code.
■	Shares sold to pay Janney fees but only if the transaction is initiated by Janney.
■	Shares acquired through a right of reinstatement.
■	Shares exchanged into the same share class of a different fund.

Front-end sales charge* discounts available at Janney: breakpoints, rights of accumulation, and/or letters of intent

■	Breakpoints as described in the Fund’s prospectus or SAI.
■	Rights of accumulation (“ROA”), which entitle shareholders to breakpoint discounts, will be automatically calculated based on the aggregated holding of BlackRock Fund assets held by accounts within the purchaser’s household at Janney. Eligible BlackRock Fund assets not held at Janney may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets.
■	Letters of intent which allow for breakpoint discounts based on anticipated purchases within a BlackRock Fund, over a 13-month time period. Eligible BlackRock Fund assets not held at Janney Montgomery Scott may be included in the calculation of letters of intent only if the shareholder notifies his or her financial advisor about such assets.

*Also referred to as an “initial sales charge.”

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Merrill Lynch:

Shareholders purchasing Fund shares through a Merrill Lynch platform or account (excluding shares purchased from or through the Fund, the Fund’s distributor or any non-Merrill Lynch platform or account, even if Merrill Lynch serves as broker-dealer of record for such shares) will be eligible only for the following sales charge waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in this Fund’s prospectus or SAI.

Front-end Sales Charge Waivers on Investor A Shares available at Merrill Lynch

■	Shares purchased by employer-sponsored retirement, deferred compensation and employee benefit plans (including health savings accounts) and trusts used to fund those plans, provided that the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan/plan participants
■	Shares purchased by a 529 Plan (does not include 529 Plan units or 529-specific share classes or equivalents)
■	Shares purchased through a Merrill Lynch affiliated investment advisory program
■	Exchanges of shares purchased through a Merrill Lynch affiliated investment advisory program due to the holdings moving from such Merrill Lynch affiliated investment advisory program to a Merrill Lynch brokerage (non-advisory) account pursuant to Merrill Lynch’s policies relating to sales charge discounts and waivers
■	Shares purchased by third party investment advisors on behalf of their advisory clients through Merrill Lynch’s platform
■	Shares of funds purchased through the Merrill Edge Self-Directed platform (if applicable)
■	Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other BlackRock Fund)
■	Shares exchanged from Investor C (i.e. level-load) shares of the same Fund pursuant to Merrill Lynch’s policies relating to sales charge discounts and waivers
■	Shares purchased by employees and registered representatives of Merrill Lynch or its affiliates and their family members
■	Shares purchased by directors of the Fund, and employees of BlackRock or any of its affiliates, as described in the prospectus
■	Eligible shares purchased from the proceeds of redemptions from another BlackRock Fund, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement). Automated transactions (i.e., systematic purchases and withdrawals) and purchases made after shares are automatically sold to pay Merrill Lynch’s account maintenance fees are not eligible for reinstatement.

CDSC Waivers on Investor A and C Shares available at Merrill Lynch

■	Shares sold due to death or disability of the shareholder
■	Shares sold as part of a systematic withdrawal plan as described in the Fund’s prospectus
■	Shares bought due to return of excess contributions from an IRA Account
■	Shares sold as part of a required minimum distribution for IRA and retirement accounts pursuant to the Internal Revenue Code
■	Shares sold to pay Merrill Lynch fees but only if the transaction is initiated by Merrill Lynch
■	Shares acquired through a Right of Reinstatement
■	Investor A and C Shares of a Fund held in the following IRA or other retirement brokerage accounts: Traditional IRAs, Roth IRAs, Rollover IRAs, Inherited IRAs, SEP IRAs, SIMPLE IRAs, BASIC Plans, Educational Savings Account and Medical Savings Accounts that are exchanged for Institutional shares of the same Fund due to transfer to certain fee based accounts or platforms
■	Investor A Shares sold, where such Investor A Shares were received as a result of exchanges of shares purchased through a Merrill Lynch affiliated investment advisory program due to the holdings moving from the program to a Merrill Lynch brokerage (non-advisory) account pursuant to Merrill Lynch’s policies relating to sales charge discounts and waivers

Front-end Sales Charge Discounts Available at Merrill Lynch: Breakpoints, Rights of Accumulation & Letters of Intent

■	Breakpoints as described in this prospectus

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Morgan Stanley Wealth Management:

Morgan Stanley Wealth Management Investor A Share Front-End Sales Charge Waiver

Effective July 1, 2018, Morgan Stanley Wealth Management clients purchasing Investor A Shares of the Fund through Morgan Stanley’s transactional brokerage accounts are entitled to a waiver of the front-end sales charge in the following circumstances:

■	Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans does not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans
■	Morgan Stanley employee and employee-related accounts according to Morgan Stanley’s account linking rules
■	Shares purchased through reinvestment of dividends and capital gains distributions when purchasing shares of the same fund
■	Shares purchased through a Morgan Stanley self-directed brokerage account
■	Investor C Shares that are no longer subject to a contingent deferred sales charge and are exchanged for Investor A Shares of the same fund pursuant to Morgan Stanley Wealth Management’s share class conversion program
■	Shares purchased from the proceeds of redemptions within BlackRock Funds under a Rights of Reinstatement provision, provided the repurchase occurs within 90 days following the redemption, the redemption and purchase occur in the same account, and redeemed shares were subject to a front-end or deferred sales charge

Unless specifically described above, no other front-end sales charge waivers are available to mutual fund purchases by Morgan Stanley Wealth Management clients through Morgan Stanley’s transactional brokerage accounts.

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Oppenheimer & Co. Inc.:

Effective May 1, 2020, shareholders purchasing Fund shares through an Oppenheimer & Co. Inc. (“OPCO”) platform or account are eligible only for the following sales charge waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this Fund’s prospectus or SAI.

Front-End Sales Charge Waivers on Investor A Shares available at OPCO

■	Shares purchased by employer-sponsored retirement, deferred compensation and employee benefit plans (including health savings accounts) and trusts used to fund those plans, provided that the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan
■	Shares purchased by or through a 529 Plan
■	Shares purchased through an OPCO affiliated investment advisory program
■	Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other BlackRock Fund)
■	Shares purchased from the proceeds of redemptions from another BlackRock Fund, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement)
■	A shareholder in the Fund’s Investor C Shares will have their shares converted at net asset value to Investor A Shares (or the appropriate share class) of the Fund if the shares are no longer subject to a CDSC and the conversion is in line with the policies and procedures of OPCO
■	Shares purchased by employees and registered representatives of OPCO or its affiliates and their family members
■	Shares purchased by directors or trustees of the Fund, and employees of the Fund’s investment adviser or any of its affiliates, as described in this prospectus

CDSC Waivers on Investor A and C Shares available at OPCO

■	Shares sold due to death or disability of the shareholder
■	Shares sold as part of a systematic withdrawal plan as described in the Fund’s prospectus
■	Shares bought due to return of excess contributions from an IRA account
■	Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable IRS regulations as described in the prospectus
■	Shares sold to pay OPCO fees but only if the transaction is initiated by OPCO
■	Shares acquired through a right of reinstatement

Front-End Sales Charge Discounts Available at OPCO: Breakpoints, Rights of Accumulation & Letters of Intent

■

Breakpoints as described in this prospectus

■

Rights of Accumulation (“ROA”) and Letters of Intent (“LOI”) which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of BlackRock Fund assets held by accounts within the purchaser’s household at OPCO. Eligible BlackRock Fund assets not held at OPCO may be included in the ROA or LOI calculation only if the shareholder notifies his or her financial advisor about such assets

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Raymond James & Associates, Inc., Raymond James Financial Services, Inc. and Each Entity’s Affiliates (“Raymond James”):

Effective March 1, 2019, shareholders purchasing Fund shares through a Raymond James platform or account, or through an introducing broker-dealer or independent registered investment adviser for which Raymond James provides trade execution, clearance, and/or custody services, will be eligible only for the following sales charge waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in this prospectus or the SAI.

Front-End Sales Charge Waivers on Investor A Shares Available at Raymond James

■	Shares purchased in a Raymond James investment advisory program.
■	Shares purchased of the same Fund or another BlackRock Fund through a systematic reinvestment of capital gains distributions and dividend distributions.
■	Shares purchased by employees and registered representatives of Raymond James or its affiliates and their family members as designated by Raymond James.
■	Shares purchased from the proceeds of redemptions from another BlackRock Fund, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement).
■	A shareholder in the Fund’s Investor C shares will have their shares converted at net asset value to Investor A shares of the Fund if the shares are no longer subject to a CDSC and the conversion is in line with the policies and procedures of Raymond James.

CDSC Waivers on Investor A and C Shares Available at Raymond James

■	Shares sold due to death or disability of the shareholder.
■	Shares sold as part of a systematic withdrawal plan as described in the Fund’s prospectus.
■	Shares bought due to return of excess contributions from an IRA Account.
■	Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable IRS regulations as described in the Fund’s prospectus or SAI.
■	Shares sold to pay Raymond James fees but only if the transaction is initiated by Raymond James.
■	Shares acquired through a Right of Reinstatement.

Front-End Sales Charge Discounts Available at Raymond James: Breakpoints, Rights of Accumulation and/or Letters of Intent

■	Breakpoints as described in this prospectus.
■	Rights of accumulation which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of BlackRock Fund assets held by accounts within the purchaser’s household at Raymond James. Eligible BlackRock Fund assets not held at Raymond James may be included in the calculation of rights of accumulation only if the shareholder notifies his or her financial advisor about such assets.
■	Letters of intent which allow for breakpoint discounts based on anticipated purchases of BlackRock Funds over a 13-month time period. Eligible BlackRock Fund assets not held at Raymond James may be included in the calculation of letters of intent only if the shareholder notifies his or her financial advisor about such assets.

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Robert W. Baird & Co. (“Baird”):

Effective June 15, 2020, shareholders purchasing Fund shares through a Baird platform or account will only be eligible for the following sales charge waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in this Fund’s prospectus or SAI

Front-End Sales Charge Waivers on Investor A Shares Available at Baird

■	Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing share of the same fund
■	Shares purchased by employees and registered representatives of Baird or its affiliates and their family members as designated by Baird
■	Shares purchased from the proceeds of redemptions from another BlackRock Fund, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement)
■	A shareholder in the Fund’s Investor C shares will have their shares converted at net asset value to Investor A shares of the fund if the shares are no longer subject to CDSC and the conversion is in line with the policies and procedures of Baird
■	Shares purchased by employer-sponsored retirement plans or charitable accounts in a transactional brokerage account at Baird, including 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans. For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs or SAR-SEPs

CDSC Waivers on Investor A and C Shares Available at Baird

■	Shares sold due to death or disability of the shareholder
■	Shares sold as part of a systematic withdrawal plan as described in the Fund’s prospectus
■	Shares bought due to returns of excess contributions from an IRA account
■	Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable Internal Revenue Service regulations as described in the Fund’s prospectus
■	Shares sold to pay Baird fees but only if the transaction is initiated by Baird
■	Shares acquired through a right of reinstatement

Front-End Sales Charge Discounts Available at Baird: Breakpoints, Rights of Accumulation, & Letters of Intent

■	Breakpoints as described in this prospectus
■	Rights of Accumulation (“ROA”) which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of BlackRock Fund assets held by accounts within the purchaser’s household at Baird. Eligible BlackRock Fund assets not held at Baird may be included in ROA calculation only if the shareholder notifies his or her financial advisor about such assets
■	Letters of Intent (“LOI”) allow for breakpoint discounts based on anticipated purchases of BlackRock Funds through Baird, over a 13-month period of time

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Additional Information

For more information:
This prospectus contains important information you should know before investing, including information about risks. Please read it before you invest and keep it for future reference. More information about the Fund is available at no charge upon request. This information includes:

Annual/Semi-Annual Reports
These reports contain additional information about the Fund’s investments.

Statement of Additional Information
A Statement of Additional Information (“SAI”), dated August 28, 2023, has been filed with the Securities and Exchange Commission (the “SEC”). The SAI, which includes additional information about the Fund, may be obtained free of charge, along with the Fund’s annual and semi-annual reports, by calling (800) 441-7762. The SAI, as amended and/or supplemented from time to time, is incorporated by reference into this prospectus.

BlackRock Investor Services
Representatives are available to discuss mutual fund prospectuses, literature, programs and services available. Hours: 8:00 a.m. to 6:00 p.m. (Eastern time), on any business day. Call: (800) 441-7762.

Purchases and Redemptions
Call your Financial Intermediary or BlackRock Investor Services at (800) 441-7762.

World Wide Web
General Fund information, including the SAI and annual/semi-annual reports, can be accessed free of charge at www.blackrock.com/prospectus/cash. Mutual fund prospectuses and literature can also be requested via this website.

Written Correspondence
BlackRock Summit Cash Reserves Fund
of BlackRock Financial Institutions Series Trust
P.O. Box 534429
Pittsburgh, Pennsylvania 15253-4429

Overnight Mail
BlackRock Summit Cash Reserves Fund
of BlackRock Financial Institutions Series Trust
Attention: 534429
500 Ross Street 154-0520
Pittsburgh, Pennsylvania 15262

Internal Wholesalers/Broker Dealer Support
Available on any business day to support investment professionals. Call: (800) 882-0052.

Portfolio Characteristics and Holdings
A description of the Fund’s policies and procedures related to disclosure of portfolio characteristics and holdings is available in the SAI.

For information about portfolio holdings and characteristics, BlackRock fund shareholders and prospective investors may call (800) 882-0052.

Securities and Exchange Commission
You may also view and copy public information about the Fund, including the SAI, by visiting the EDGAR database on the SEC’s website (http://www.sec.gov). Copies of this information can be obtained, for a duplicating fee, by electronic request at the following e-mail address: [email protected].

You should rely only on the information contained in this prospectus. No one is authorized to provide you with information that is different from information contained in this prospectus.

The SEC has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

INVESTMENT COMPANY ACT FILE # 811-03189

PRO-SUMM-INST-0823

For More Information	Fund and Service Providers	Inside Back Cover
	Additional Information	Back Cover

•	BlackRock Summit Cash Reserves Fund
	Investor A: MSAXX • Investor C: MCBXX • Institutional: MSIXX


Fund Overview	Key facts and details about the Fund, including investment objective, principal investment strategies, principal risk factors, fee and expense information and historical performance information
	Investment Objective	3
	Fees and Expenses of the Fund	3
	Principal Investment Strategies of the Fund	4
	Principal Risks of Investing in the Fund	4
	Performance Information	6
	Investment Manager	6
	Purchase and Sale of Fund Shares	7
	Tax Information	8
	Payments to Broker/Dealers and Other Financial Intermediaries	8


Details About the Fund	Information about how the Fund invests, including investment objective, investment processes, principal strategies and risk factors
	How the Fund Invests	10
	Investment Risks	11


Account Information	Information about account services, sales charges and waivers, shareholder transactions, and distribution and other payments
	How to Choose the Share Class that Best Suits Your Needs	15
	Details About the Share Classes	19
	Distribution and Shareholder Servicing Payments	22
	How to Buy, Sell, Exchange and Transfer Shares	22
	Account Services and Privileges	28
	Fund’s Rights	29
	Participation in Fee-Based Programs	29
	Short-Term Trading Policy	30


Management of the Fund	Information about BlackRock
	BlackRock	31
	Conflicts of Interest	32
	Valuation of Fund Investments	33
	Dividends, Distributions and Taxes	33