December 29, 2023

PROSPECTUS

MFS^® U.S. Government Cash Reserve Fund

The investment objective of the fund is to seek current income consistent with preservation of capital and liquidity.

class		ticker symbol
Class A		MSRXX
Class B		MCRXX
Class C		MCCXX
Class I		CRHXX
Class R1		CRVXX
Class R2		CRMXX
Class R3		CRJXX
Class R4		CRKXX
Class R6		CRRXX

Table of contents

SUMMARY OF KEY INFORMATION 2

INVESTMENT OBJECTIVE, STRATEGIES, AND RISKS 5

MANAGEMENT OF THE FUND 6

DESCRIPTION OF SHARE CLASSES 7

HOW TO PURCHASE, REDEEM, AND EXCHANGE SHARES 10

OTHER INFORMATION 14

FINANCIAL HIGHLIGHTS 16

APPENDIX A – WAIVERS AND REDUCTIONS OF SALES CHARGES A-1

The Securities and Exchange Commission has not approved or disapproved the fund’s shares or determined whether this prospectus is accurate or complete. Anyone who tells you otherwise is committing a crime.

LMM-PRO-122923

MFS U.S. Government Cash Reserve Fund

Summary of Key Information

Investment Objective

The fund’s investment objective is to seek current income consistent with preservation of capital and liquidity.

Fees and Expenses

This table describes the fees and expenses that you may pay when you buy, hold, and sell shares of the fund. Investors may also pay commissions or other fees to their financial intermediaries when they buy, hold, and sell shares of the fund, which are not reflected below.

Shareholder Fees (fees paid directly from your investment):

Share Class	A			B			C			I			R1			R2			R3			R4			R6
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	None			None			None			None			None			None			None			None			None
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)		None			4.00	%		1.00	%		None			None			None			None			None			None

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

Share Class	A			B			C			I			R1			R2			R3			R4			R6
Management Fee		0.40	%		0.40	%		0.40	%		0.40	%		0.40	%		0.40	%		0.40	%		0.40	%		0.40	%
Distribution and/or Service (12b-1) Fees		0.25	%		1.00	%		1.00	%		None			1.00	%		0.50	%		0.25	%		None			None
Other Expenses		0.19	%		0.19	%		0.19	%		0.19	%		0.19	%		0.19	%		0.19	%		0.19	%		0.13	%
Total Annual Fund Operating Expenses		0.84	%		1.59	%		1.59	%		0.59	%		1.59	%		1.09	%		0.84	%		0.59	%		0.53	%
Fee Reductions and/or Expense Reimbursements¹		(0.39	)%		(1.14	)%		(1.14	)%		(0.14	)%		(1.14	)%		(0.64	)%		(0.39	)%		(0.14	)%		(0.16	)%
Total Annual Fund Operating Expenses After Fee Reductions and/or Expense Reimbursements		0.45	%		0.45	%		0.45	%		0.45	%		0.45	%		0.45	%		0.45	%		0.45	%		0.37	%

Massachusetts Financial Services Company (MFS) has agreed in writing to waive at least 0.01% of the fund’s management fee as part of an agreement pursuant to which MFS has agreed to reduce its management fee by a specified amount if certain MFS mutual fund assets exceed thresholds agreed to by MFS and the fund’s Board of Trustees. The agreement to waive at least 0.01% of the management fee will continue until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024. MFS Fund Distributors, Inc. (MFD), has agreed in writing to waive the Class B, Class C, Class R1, and Class R2 distribution fee to 0.00% of each class’ average daily net assets annually until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024. MFD has agreed in writing to waive the Class A, Class B, Class C, Class R1, Class R2, and Class R3 service fee to 0.00% of each class’ average daily net assets annually until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024. MFS has agreed in writing to bear the fund’s expenses, excluding interest, taxes, extraordinary expenses, brokerage and transaction costs, and investment-related expenses (such as interest and borrowing expenses incurred in connection with the fund’s investment activity), such that “Total Annual Fund Operating Expenses” do not exceed 0.45% of the class’ average daily net assets annually for each of Class A, Class B, Class C, Class I, Class R1, Class R2, Class R3, and Class R4 shares, and 0.37% of the class’ average daily net assets annually for Class R6 shares. This written agreement will continue until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024.

MFS U.S. Government Cash Reserve 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 you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund’s operating expenses remain the same.

Although your actual costs will likely be higher or lower, under these assumptions your costs would be:

	1 YEAR		3 YEARS		5 YEARS		10 YEARS
Class A Shares	$	46	$	229	$	428	$	1,001
Class B Shares assuming¹
redemption at end of period	$	446	$	690	$	958	$	1,589
no redemption at end of period	$	46	$	390	$	758	$	1,589
Class C Shares assuming¹
redemption at end of period	$	146	$	390	$	758	$	1,589
no redemption at end of period	$	46	$	390	$	758	$	1,589
Class I Shares	$	46	$	175	$	315	$	725
Class R1 Shares	$	46	$	390	$	758	$	1,793
Class R2 Shares	$	46	$	283	$	539	$	1,271
Class R3 Shares	$	46	$	229	$	428	$	1,001
Class R4 Shares	$	46	$	175	$	315	$	725
Class R6 Shares	$	38	$	154	$	280	$	650

Shares automatically convert to Class A shares approximately eight years after purchase; therefore, the expense examples reflect Class A share expenses after eight years.

Principal Investment Strategies

MFS (Massachusetts Financial Services Company, the fund’s investment adviser) normally invests at least 99.5% of the fund’s total assets in cash, U.S. Government money market instruments, and/or repurchase agreements collateralized by cash or U.S. Government securities. MFS normally invests at least 80% of the fund’s net assets in U.S. Government money market instruments and repurchase agreements collateralized by U.S. Government securities.

In buying and selling investments for the fund, MFS follows U.S. Securities and Exchange Commission rules for money market funds regarding credit quality, diversification, liquidity, and maturity. MFS stresses maintaining a stable $1.00 per share price, liquidity, and income.

For purposes of the fund’s 80% policy, net assets include the amount of any borrowings for investment purposes.

Principal Risks

You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the fund is 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 principal risks of investing in the fund are:

Credit and Market Risk: The value of a money market instrument depends on the credit quality of the issuer, borrower, counterparty, or other entity responsible for payment. The value of a money market instrument can also decline in response to changes in, or perceptions of, the financial condition of the issuer or borrower, changes in, or perceptions of, specific market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions that affect a particular type of instrument, issuer, or borrower, and changes in, or perceptions of, general market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions.

Investment Selection Risk: MFS’ investment analysis and its selection of investments may not produce the intended results and/or can lead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperforming the markets in which the fund invests. In addition, to the extent MFS considers quantitative tools in managing the fund, such tools may not produce the intended results.

Redemption Risk: Large or frequent redemptions could cause the fund’s share price to decrease to below $1.00 per share.

Focus Risk: If MFS invests a significant percentage of the fund’s assets in a single issuer or small number of issuers, the fund’s performance could be more volatile than the performance of more diversified funds.

Counterparty and Third Party Risk: Transactions involving a counterparty or third party other than the issuer of the instrument are subject to the credit risk of the counterparty or third party, and to the counterparty’s or third party’s ability or willingness to perform in accordance with the terms of the transaction.

Liquidity Risk: It may be difficult to value, and it may not be possible to sell, certain investments, types of investments, and/or investments in certain segments of the market, and the fund may have to sell certain of these investments at prices or times that are not advantageous in order to meet redemptions or other cash needs.

Performance Information

The bar chart and performance table below are intended to provide some indication of the risks of investing in the fund by showing changes in the fund’s performance over time.

Performance information prior to July 1, 2014, reflects time periods when the fund was not considered a U.S. Government money market fund and had different investment policies and strategies. The fund’s investment policies and strategies changed effective July 1, 2014. The fund’s past performance does not necessarily indicate

MFS U.S. Government Cash Reserve Fund

how the fund will perform in the future. Updated performance is available online at mfs.com or by calling 1-800-225-2606.

Class A Bar Chart.

The total return for the nine-month period ended September 30, 2023, was 3.30%. During the period(s) shown in the bar chart, the highest quarterly return was 0.76% (for the calendar quarter ended December 31, 2022) and the lowest quarterly return was 0.00% (for the calendar quarter ended March 31, 2022).

Performance Table.

Average Annual Total Returns

(For the Periods Ended December 31, 2022)

Share Class	1 YEAR			5 YEARS			10 YEARS
A Shares		1.19	%		0.79	%		0.41	%
B Shares		(2.81	)%		0.40	%		0.41	%
C Shares		0.19	%		0.79	%		0.41	%
I Shares		1.19	%		0.79	%		0.41	%
R1 Shares		1.19	%		0.79	%		0.41	%
R2 Shares		1.19	%		0.79	%		0.41	%
R3 Shares		1.19	%		0.79	%		0.41	%
R4 Shares		1.19	%		0.79	%		0.41	%
R6 Shares		1.22	%		0.82	%		0.43	%

Investment Adviser

MFS serves as the investment adviser for the fund.

Purchase and Sale of Fund Shares

You may purchase and redeem shares of the fund each day the New York Stock Exchange (the NYSE) is open for trading. You may purchase or redeem shares either by having your financial intermediary process your purchase or redemption, or through MFS Service Center, Inc. (MFSC) by overnight mail (MFSC, Suite 219341, 430 W 7^th Street, Kansas City, MO 64105-1407), by mail ([Fund Name], P.O. Box 219341, Kansas City, MO 64121-9341), by telephone (1-800-225-2606), or via the Internet at mfs.com (MFS Access).

The fund’s initial and subsequent investment minimums generally are as follows:

Class

Initial Minimum

Subsequent Minimum

Class A, Class B, Class C

None – automatic investment plans and certain asset-based fee programs

$25 – employer-sponsored retirement plans

$250 – Traditional and Roth IRAs

$1,000 – other accounts

$50 – by check and non-systematic written exchange request, and via MFSC telephone representatives

None – other purchases

Class I, Class R1, Class R2, Class R3, Class R4, Class R6

None

Effective at the close of business on May 29, 2020 (the Closing Date), the fund is closed to all purchases except: 1) purchases through the reinvestment of distributions in the fund; 2) purchases as a result of exchanges from another MFS fund; 3) purchases as a result of shareholders exercising their one-time Reinstatement Privilege (described in Appendix A of this prospectus) to reinvest in shares of the fund within 90 days of a redemption of fund shares; 4) purchases in connection with a shareholder’s transfer of some or all of the shares in the shareholder’s account to another account; 5) purchases by retirement plans other than traditional IRAs, SIMPLE IRAs, Roth IRAs, SEP plans, and SARSEP plans if the fund was offered or officially selected as an investment option by such plan (or any predecessor plan or other plan sponsored by the same employer) as of the Closing Date; 6) purchases by qualified tuition programs established under Section 529 of the Internal Revenue Code of 1986, as amended, if the fund was offered as an investment option by such program on the Closing Date; and 7) investors approved by the fund, the fund’s investment adviser, and the fund’s distributor.

The fund reserves the right to modify or limit the above exceptions or re-open the fund at any time without prior notice.

Financial intermediaries are responsible for enforcing these restrictions with respect to their investors. MFS’ ability to monitor financial intermediaries’ enforcement of these restrictions is limited by operational systems and the cooperation of financial intermediaries. In addition, with respect to omnibus accounts, MFS’ ability to monitor is also limited by a lack of information with respect to the underlying shareholder accounts.

Purchases of Class B shares are closed to new and existing investors except through reinvestment of dividends and capital gain distributions. Existing investors may continue to exchange their Class B shares for the same share class of another MFS fund.

Purchases of Class R1 and Class R2 shares are closed to new eligible investors. Existing eligible investors can make additional purchases and reinvest distributions in Class R1 and Class R2 shares in any account open. Existing eligible investors may also exchange their Class R1 and Class R2 shares for the same share class of another MFS fund, open new Class R1 and Class R2 share accounts in other MFS funds, and transfer some or all of the shares in their account to another account and such account will be treated as having been open. Subject to the approval of the fund’s Board of Trustees, the fund may in the future (i) close purchases of Class R1 and/or Class R2 shares to existing eligible investors; (ii) terminate and liquidate Class R1 and/or Class R2 shares; or (iii) convert Class R1 and/or Class R2 shares to another share class of the fund. Such actions may be undertaken without shareholder approval, but the fund expects to provide shareholders with at least 60 days’ notice before taking any such action.

MFS U.S. Government Cash Reserve Fund

Taxes

If your shares are held in a taxable account, the fund’s distributions will be taxed to you as ordinary income and/or capital gains. The fund expects that substantially all its distributions will consist of investment income taxable as ordinary income. If your shares are held in a tax-advantaged account, you will generally be taxed only upon withdrawals from the account.

Payments to Broker/Dealers and Other Financial Intermediaries

If you purchase shares of the fund through a broker/dealer or other financial intermediary (such as a bank), the fund, MFS, and/or MFS’ affiliates may pay the financial intermediary for the sale of shares of the fund and/or the servicing of shareholder accounts. These payments may create a conflict of interest by influencing your broker/dealer or other financial intermediary and your salesperson to recommend the fund over another investment. Ask your financial intermediary or visit your financial intermediary’s website for more information.

Investment Objective, Strategies, and Risks

Investment Objective

The fund’s investment objective is to seek current income consistent with preservation of capital and liquidity. The fund’s objective may be changed without shareholder approval.

Principal Investment Strategies

MFS normally invests at least 99.5% of the fund’s total assets in cash, U.S. Government money market instruments, and/or repurchase agreements collateralized by cash or U.S. Government securities. MFS normally invests at least 80% of the fund’s net assets in U.S. Government money market instruments and repurchase agreements collateralized by U.S. Government securities.

For purposes of the fund’s 80% policy, net assets include the amount of any borrowings for investment purposes.

Principal Investment Types

The principal investment types in which the fund may invest are:

U.S. Government Money Market Instruments: U.S. Government money market instruments are short-term instruments issued or guaranteed as to the payment of principal and interest by the U.S. Treasury, by an agency or instrumentality of the U.S. Government, or by a U.S. Government-sponsored entity that pay a fixed, variable, or floating interest rate. Certain U.S. Government securities are not supported as to the payment of principal and interest by the full faith and credit of the U.S. Treasury or the ability to borrow from the U.S. Treasury. Some U.S. Government securities are supported as to the payment of principal and interest only by the credit of the entity issuing or guaranteeing the security. U.S. Government securities include mortgage-backed securities and other types of asset-backed securities issued or guaranteed by the U.S. Treasury, by an agency or instrumentality of the U.S. Government, or by a U.S. Government-sponsored entity.

Repurchase Agreements: Repurchase agreements are agreements to buy a security from a third party at one price, with simultaneous agreements to sell it back to the third party at an agreed-upon price.

Principal Risks

The fund’s yield will change daily based on changes in interest rates and other market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. 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 significance of any specific risk to an investment in the fund will vary over time depending on the composition of the fund’s portfolio, market conditions, and other factors. You should read all of the risk information below carefully, because any one or more of these risks may result in losses to the fund.

The principal risks of investing in the fund are:

Interest Rate Risk: In general, the price of a money market instrument falls when interest rates rise and rises when interest rates fall. A major or unexpected increase in interest rates could cause the fund’s share price to decrease to below $1.00 per share. The fund may face a heightened level of interest rate risk due to changes in monetary policy. When interest rates go down, the fund’s yield may decline. Also, when interest rates decline, the fund’s investments may pay a lower interest rate, which would reduce the income received by the fund. A low or negative interest rate environment may prevent the fund from providing a positive yield and could impair the fund’s ability to maintain a stable $1.00 per share. Inflationary price movements may cause fixed income securities markets to experience heightened levels of interest rate volatility and liquidity risk. The risks associated with rising interest rates may be particularly acute in the current market environment because the Federal Reserve Board recently raised interest rates and may continue to do so.

Redemption Risk: Large or frequent redemptions could cause the fund’s share price to decrease to below $1.00 per share.

Focus Risk: If MFS invests a significant percentage of the fund’s assets in a single issuer or small number of issuers, the fund’s performance will be affected by economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions that impact that one issuer or issuers, could be closely

MFS U.S. Government Cash Reserve Fund

tied to the value of that issuer or issuers, and could be more volatile than the performance of more diversified funds.

Counterparty and Third Party Risk: Transactions involving a counterparty other than the issuer of the instrument, including clearing organizations, or a third party responsible for servicing the instrument or effecting the transaction, are subject to the credit risk of the counterparty or third party, and to the counterparty’s or third party’s ability or willingness to perform in accordance with the terms of the transaction. If a counterparty or third party fails to meet its contractual obligations, goes bankrupt, or otherwise experiences a business interruption, the fund could miss investment opportunities, lose value on its investments, or otherwise hold investments it would prefer to sell, resulting in losses for the fund.

Liquidity Risk: Certain investments and types of investments are subject to restrictions on resale, may trade in the over-the-counter market, or may not have an active trading market due to adverse market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions, including trading halts, sanctions, or wars. Investors trying to sell large quantities of a particular investment or type of investment, or lack of market makers or other buyers for a particular investment or type of investment may also adversely affect liquidity. At times, all or a significant portion of a market may not have an active trading market. Without an active trading market, it may be difficult to value, and it may not be possible to sell, these investments and the fund could miss other investment opportunities and hold investments it would prefer to sell, resulting in losses for the fund. In addition, the fund may have to sell certain of these investments at prices or times that are not advantageous in order to meet redemptions or other cash needs, which could result in dilution of remaining investors’ interests in the fund. The prices of illiquid securities may be more volatile than more liquid investments.

Large Shareholder Risk: From time to time, shareholders of the fund (which may include institutional investors, financial intermediaries, or other MFS funds) may make relatively large redemptions or purchases of fund shares. These transactions may cause the fund to sell securities or invest additional cash, as the case may be, at disadvantageous prices. While it is impossible to predict the overall impact of these transactions over time, there could be adverse effects on the fund’s performance to the extent that the fund may be required to sell securities or invest cash at times it would not otherwise do so. Redemptions of a large number of shares also may increase transaction and other costs or have adverse tax consequences for shareholders of the fund by requiring a sale of portfolio securities. In addition, a large redemption could result in the fund’s current expenses being allocated over a smaller asset base, leading to an increase in the fund’s expense ratio. Purchases of a large number of shares may adversely affect the fund’s performance to the extent that it takes time to invest new cash and the fund maintains a larger cash position than it ordinarily would.

Other Investment Strategies and Risks

Operational and Cybersecurity Risk: The fund and its service providers, and your ability to transact with the fund, may be negatively impacted due to operational matters arising from, among other issues, human errors, systems and technology disruptions or failures, fraudulent activities, or cybersecurity incidents. Operational issues and cybersecurity incidents may cause the fund or its service providers, as well as securities trading venues and other market participants, to suffer data corruption and/or lose operational functionality, and could, among other things, interfere with the processing of shareholder transactions, impair the ability to calculate the fund’s net asset value per share, impede trading of portfolio securities, and result in the theft, misuse, and/or improper release of confidential information relating to the fund or its shareholders. Such operational issues and cybersecurity incidents may result in losses to the fund and its shareholders. Because technology is frequently changing, new ways to carry out cyberattacks continue to develop. Therefore, there is a chance that certain risks have not been identified or prepared for, or that an attack may not be detected, which puts limitations on the ability of the fund and its service providers to plan for or respond to a cyberattack. Furthermore, geopolitical tensions could increase the scale and sophistication of deliberate cybersecurity attacks, particularly those from nation-states or from entities with nation-state backing.

Temporary Defensive Strategy: In response to adverse market, economic, industry, political, or other conditions, MFS may depart from the fund’s principal investment strategies by temporarily investing for defensive purposes. When MFS invests defensively, different factors could affect the fund’s performance and the fund may not achieve its investment objective. In addition, the defensive strategy may not work as intended.

Further Information on Investment Strategies, Types, and Risks: Information about investment strategies and investment types not described in the prospectus and the risks associated with those investment strategies and investment types are described in the fund’s Statement of Additional Information (SAI).

Management of the Fund

Investment Adviser

MFS, located at 111 Huntington Avenue, Boston, Massachusetts 02199, serves as the investment adviser for the fund. Subject to the supervision of the fund’s Board of Trustees, MFS is responsible for managing the fund’s investments, executing transactions, and providing related administrative services and facilities under an Investment Advisory Agreement between the fund and MFS.

For the fiscal year ended August 31, 2023, the fund paid MFS an effective management fee equal to 0.39% of the fund’s average daily net assets.

The management fee set forth in the Investment Advisory Agreement is 0.40% of the fund’s average daily net assets annually up to $1 billion and 0.35% of the fund’s average daily net assets annually in excess of $1 billion.

MFS has voluntarily agreed to waive all or a portion of the management fee of the fund and bear some or all of the fund’s expenses to avoid a negative yield for the fund. MFS may terminate this voluntary waiver at any time. For the fiscal year ended August 31, 2023, MFS did not waive any portion of the fund’s management fee or the fund’s expenses related to this voluntary agreement.

MFS has agreed in writing to reduce its management fee by a specified amount if certain MFS mutual fund assets exceed thresholds agreed to by MFS and the fund’s Board of Trustees. MFS has agreed in writing to waive at least 0.01% of its management fee as part of this agreement. The agreement to waive at least 0.01% of the management fee will continue until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024. For the fiscal year ended August 31, 2023, this management fee reduction amounted to 0.01% of the fund’s average daily net assets.

MFS has agreed in writing to bear the fund’s expenses, excluding interest, taxes, extraordinary expenses, brokerage and transaction costs, and investment-related expenses (such as interest and borrowing expenses incurred in connection with the fund’s investment activity), such that “Total Annual Fund Operating Expenses” do not exceed 0.45% of the class’ average daily net assets

MFS U.S. Government Cash Reserve Fund

annually for each of Class A, Class B, Class C, Class I, Class R1, Class R2, Class R3, and Class R4 shares, and 0.37% of the class’ average daily net assets annually for Class R6 shares. This written agreement will continue until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024.

A discussion regarding the basis for the Board of Trustees’ approval of the Investment Advisory Agreement is available in the fund’s annual report for the one-year period ended August 31, 2023.

MFS is America’s oldest mutual fund organization. MFS and its predecessor organizations have a history of money management dating from 1924 and the founding of the first mutual fund, Massachusetts Investors Trust. Net assets under the management of the MFS organization were approximately $538 billion as of October 31, 2023.

Disclosure of Portfolio Holdings. The fund has established a policy with respect to the disclosure of fund portfolio holdings. A description of this policy is provided in the SAI.

The following information is available to you at mfs.com/openendfunds by selecting the fund’s name:

Information		Approximate Date of Posting
Fund’s top 10 holdings as of each month’s end		11 days after month end
Fund’s full holdings as of each month’s end (under “Monthly Portfolio Holding Reports”)		5 business days after month end
Fund’s full holdings as of each month’s end (under “Full and Historical Holdings”)		19 days after month end

Note that the fund or MFS may suspend the posting of this information or modify the elements of this Web posting policy without notice to shareholders. Once posted, the above information will generally remain available on mfs.com until at least the date on which the information is filed with the SEC for the period that includes the date as of which the mfs.com information is current.

Administrator

MFS provides the fund with certain financial, legal, and other administrative services under a Master Administrative Services Agreement between the fund and MFS. Under the Agreement, MFS is paid an annual fee for providing these services.

Distributor

MFS Fund Distributors, Inc. (MFD), a wholly-owned subsidiary of MFS, is the distributor of shares of the fund.

Shareholder Servicing Agent

MFS Service Center, Inc. (MFSC), a wholly-owned subsidiary of MFS, provides dividend and distribution disbursing and transfer agent and recordkeeping functions in connection with the issuance, transfer, and redemption of each class of shares of the fund under a Shareholder Servicing Agent Agreement. MFSC receives a fee based on the costs it incurs in providing these services and a target profit margin. In addition, MFSC is reimbursed for payments made to service providers that provide certain sub-accounting and other shareholder services (shareholder servicing payments) and its out-of-pocket expenses. No shareholder servicing payments are made for Class R6 shares.

Description of Share Classes

The fund offers Class A, Class B, Class C, Class I, Class R1, Class R2, Class R3, Class R4, and Class R6 shares through this prospectus. All classes of the fund have the same investment objective and investments, but each class has its own sales charge and expense structure. Your financial intermediary may also charge you additional fees, commissions, or other charges. You should consult with your financial intermediary to help you determine which class is most appropriate for you.

The fund reserves the right to modify or limit the above exceptions or re-open the fund at any time without prior notice.

Share Class Eligibility

Your financial intermediary is responsible for determining if you meet any share class eligibility requirements. MFS does not generally monitor any share class eligibility requirements.

MFS U.S. Government Cash Reserve Fund

Class A, Class B, and Class C shares do not have any share class eligibility requirements.

Class I shares generally are available only to the following eligible investors:

	●	certain retirement plans established for the benefit of employees and former employees of MFS or its affiliates;
	●	defined benefit retirement plans, endowments, or foundations;
	●	bank trust departments or law firms acting as trustee or manager for trust accounts;
	●	investors who purchase shares through asset-based fee programs available through financial intermediaries;
	●	employees and former employees of MFS and its subsidiaries who were employed by MFS or its subsidiaries on or after January 1, 2013, trusts, pension, profit-sharing or other retirement plans for the sole benefit of such persons, and joint accounts with such persons’ spouses or legal equivalents under applicable state law; and
	●	trustees and former trustees of any investment company for which MFD serves as a distributor and who served as trustee on or after January 1, 2013, trusts, pension, profit-sharing or other retirement plans for the sole benefit of such persons, and joint accounts with such persons’ spouses or legal equivalents under applicable state law.

Class I shares are also available to other institutional investors who have entered into an agreement with MFD to purchase Class I shares and investors who purchase shares through brokerage programs of certain financial intermediaries that have entered into an agreement with MFD to offer Class I shares through such programs. In addition, Class I shares are available to investors whose Class A, Class B, or Class C shares have been converted to Class I shares as a result of no financial intermediary being specified on the investor’s account. (Please see “Conversion Among Share Classes” below.)

Class R1, Class R2, Class R3, and Class R4 shares generally are available only to eligible retirement plans (401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans, defined benefit plans and non-qualified deferred compensation plans any of whose accounts are maintained by the fund at an omnibus level (“Employer Retirement Plans”)), and health savings accounts under Section 223 of the Internal Revenue Code if such accounts are maintained by the fund at an omnibus level.

Class R1, Class R2, Class R3, and Class R4 shares generally are not available to traditional and Roth IRAs, Coverdell Educational Savings Accounts, SEPs, SAR-SEPs, SIMPLE IRAs, salary reduction only 403(b) plans, and Section 529 tuition plans.

Class R6 shares generally are available only to the following eligible investors:

	●	Employer Retirement Plans;
	●	health savings accounts under Section 223 of the Internal Revenue Code if such accounts are maintained by the fund at an omnibus level;
	●	investment companies distributed by MFD;
	●	endowments and foundations, local, city and state agencies (or entities acting on their behalf);
	●	funded welfare benefit plans (e.g., Voluntary Employees’ Beneficiary Association (VEBA) and Other Post-Employment (OPEB) plans);
	●	unaffiliated registered investment companies;
	●	collective investment trusts;
	●	investors who purchase shares through asset-based fee programs of certain financial intermediaries that have entered into an agreement with MFD to offer Class R6 shares through such programs; and
	●	Section 529 tuition plans that have entered into an agreement with MFD to purchase Class R6 shares.

Effective January 1, 2024, the following bullet is added to the end of the list of bullets directly above:

●

MFS Development Funds, LLC, pooled investment vehicles established by MFS for the purpose of establishing a performance record to enable MFS and its subsidiaries to offer such vehicle’s investment style to clients.

Class R6 shares are also available to other institutional investors who have entered into an agreement with MFD to purchase Class R6 shares and investors who purchase shares through brokerage programs of certain financial intermediaries that have entered into an agreement with MFD to offer Class R6 shares through such programs.

Conversion Among Share Classes

If you hold Class B shares for approximately eight years, they will convert to Class A shares of the fund. For purposes of calculating the conversion date, purchases made on any day during a calendar month will age one month at the close of business on the last day of that month, and at the close of business on the last day of each subsequent month.

All Class B shares you acquire through the reinvestment of dividends and distributions will be held in a separate sub-account. Each time any Class B shares in your account convert to Class A shares, a proportionate number of the Class B shares in the sub-account will also convert to Class A shares.

For shareholders invested in Class B shares through a financial intermediary, it is the responsibility of the financial intermediary to ensure that the investor is credited with the proper holding period. The automatic conversion of Class B shares to Class A shares will not apply to shares held through financial intermediaries that do not track the length of time that a shareholder has held such shares. Please consult your financial intermediary for more information.

If you hold Class C shares for approximately eight years, they will convert to Class A shares of the fund. For purposes of calculating the conversion date, purchases made on any day during a calendar month will age one month at the close of business on the last day of that month, and at the close of business on the last day of each subsequent month.

All Class C shares you acquire through the reinvestment of dividends and distributions will be held in a separate sub-account. Each time any Class C shares in your account convert to Class A shares, a proportionate number of the Class C shares in the sub-account will also convert to Class A shares.

For shareholders invested in Class C shares through a financial intermediary, it is the responsibility of the financial intermediary to ensure that the investor is credited with the proper holding period. The automatic conversion of Class C shares to Class A shares will not apply to shares held through financial intermediaries that do not track the length of time that a shareholder has held such shares. In addition, for shareholders invested in Class C shares through a

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financial intermediary, Class C shares may be automatically exchanged for Class A shares of the fund under the policies of the financial intermediary, as described in Appendix A of this prospectus. It is solely the responsibility of the respective financial intermediary to administer and support such transactions. Please consult your financial intermediary for more information.

Class C shareholders of the fund may be able to convert their shares to Class A shares of the fund if their financial intermediary provides written notification to MFD prior to such conversion that the intermediary has determined that Class A was the appropriate share class at the time of purchase for such shareholder and receives approval of such conversion by MFD. Class C shareholders also may be able to convert their Class C shares not subject to a CDSC to Class I shares of the fund if they satisfy eligibility requirements of Class I shares.

Shareholders may be able to convert between Class A shares and Class I shares of the fund if they satisfy eligibility requirements for the other class, if any. Class I shareholders may be able to convert their Class I shares to Class R6 shares of the fund if they satisfy eligibility requirements of Class R6 shares.

Class A, Class B, or Class C shares in an account held directly with MFSC for which no financial intermediary is specified will be periodically converted to Class I shares as authorized by MFD. If your Class A, Class B, or Class C shares are converted to Class I shares pursuant to this conversion feature, all future purchases in your account will be invested in Class I shares. Shareholders will generally be provided with written notice at least 30 days prior to a conversion of their Class A, Class B, or Class C shares to Class I shares.

If a shareholder converts from one share class to another share class of the fund, as described above, the transaction will be based on the respective net asset value of each class as of the trade date for the conversion. Consequently, the converting shareholder may receive fewer shares or more shares than originally owned, depending on that day’s net asset values. The total value of the initially held shares, however, will equal the total value of the converted shares received. A conversion between share classes in the same fund, as described above, is a nontaxable event for federal income tax purposes.

Sales Charges and Waivers and Reductions

You may be subject to a CDSC when you redeem Class B or Class C shares. These sales charges are paid to MFD.

You may qualify for a sales charge waiver when you redeem shares. The waivers that are applicable to your transaction depend on your financial intermediary and the type of account and transaction. Further details regarding these waivers are provided in Appendix A of this prospectus. You or your financial intermediary must inform MFSC upon redeeming fund shares of your eligibility for a sales charge waiver. Waivers may be eliminated, modified, and added at any time without providing advance notice to shareholders.

Class A Shares. You may purchase Class A shares at net asset value without an initial sales charge or a CDSC upon redemption. If you exchange Class A shares of another MFS fund that are subject to a CDSC into the fund, you will pay the CDSC, if applicable, upon redemption of such shares from the fund.

Class B Shares. Class B shares are not subject to an initial sales charge, but if you redeem your shares within the first six years after purchase, you may be subject to a CDSC (declining from 4% during the first year to 0% after six years).

The CDSC is imposed according to the following schedule:

Year of redemption after purchase		1st				2nd				3rd				4th				5th				6th				7th
Contingent deferred sales charge			4	%			4	%			3	%			3	%			2	%			1	%			0	%

Class C Shares. You may purchase Class C shares at net asset value without an initial sales charge. However, a CDSC of 1% will generally be deducted from your redemption proceeds if you redeem within 12 months of your purchase.

Class I Shares. Eligible investors may purchase Class I shares at net asset value without an initial sales charge or a CDSC upon redemption.

Class R1, Class R2, Class R3, Class R4, and Class R6 Shares. Eligible investors may purchase Class R1, Class R2, Class R3, Class R4, and Class R6 shares at net asset value without an initial sales charge or a CDSC upon redemption.

Calculation Of CDSC. As discussed above, certain investments in Class A, Class B, and Class C shares are subject to a CDSC. For purposes of calculating the CDSC, purchases made on any day during a calendar month will age one month at the close of business on the last day of that month, and at the close of business on the last day of each subsequent month. The CDSC is based on the original purchase cost or the current market value of the shares being sold, whichever is less. For purposes of determining the CDSC, if you sell only some of your shares, shares not subject to a CDSC are sold first, followed by shares held the longest.

Shares acquired through reinvestment of distributions are not subject to a CDSC.

Distribution and Service Fees

The fund has adopted a plan in accordance with Rule 12b-1 under the Investment Company Act of 1940, as amended (the “Distribution Plan”). Under the Distribution Plan, the fund pays distribution and/or service fees to MFD to support the sale and distribution of Class A, Class B, Class C, Class R1, Class R2, and Class R3 shares, and/or shareholder servicing and account maintenance activities. These distribution and/or service fees equal on an annual basis up to the following maximum percentages of average daily net assets of the class:

CLASS	Maximum Distribution Fee			Maximum Service Fee			Maximum Total Distribution and Service Fee
Class A		0.00	%		0.25	%		0.25	%
Class B		0.75	%		0.25	%		1.00	%
Class C		0.75	%		0.25	%		1.00	%
Class R1		0.75	%		0.25	%		1.00	%
Class R2		0.25	%		0.25	%		0.50	%
Class R3		0.00	%		0.25	%		0.25	%

These fees are paid out of fund assets of the applicable class of shares. Because these fees are an ongoing expense of the fund, they increase the cost of your investment over time and may cost you more than other types of sales charges.

MFD has agreed in writing to waive the Class A, Class B, Class C, Class R1, Class R2, and Class R3 service fee to 0.00% of each class’ average daily net assets annually until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024.

MFD has agreed in writing to waive the Class B, Class C, Class R1, and Class R2 distribution fee to 0.00% of each class’ average daily

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net assets annually until modified by the fund’s Board of Trustees, but such agreement will continue until at least December 31, 2024.

The fund has not adopted a Rule 12b-1 plan with respect to its Class I, Class R4, or Class R6 shares.

Financial Intermediary Compensation

The term “financial intermediary” refers to any broker/dealer, bank (including bank trust departments), registered investment adviser, financial planner, retirement plan administrator, third-party administrator, insurance company, consultant, and any other institution having a selling, administration, or any similar agreement with MFD, MFS, or any of their affiliates.

Financial intermediaries receive various forms of compensation in connection with the sale of shares of a fund and/or the servicing of shareholder accounts. Financial intermediaries receive such compensation (i) in the form of up-front commissions and ongoing asset-based compensation paid by MFD based on sales charges received and expected to be received by MFD from shareholders and Distribution Plan distribution and service payments received by MFD from the fund, (ii) in the form of shareholder servicing payments paid by an affiliate of MFD based on the receipt of such payments by MFD or its affiliates from the fund, and/or (iii) in the form of payments paid by MFD from MFD’s own additional resources.

Financial intermediaries receive up-front commissions of up to the following percentage amount(s) for sales of the following share class(es):

SHARE CLASS	UP FRONT COMMISSION AS A PERCENTAGE OF OFFERING PRICE
Class A	N/A
Class B	3.75	%
Class C	1.00	%

In addition, certain financial intermediaries receive payments from MFD from MFD’s own additional resources as incentives to market the MFS funds, to participate in MFD’s promotional efforts and/or in recognition of their marketing support, administrative services, and/or transaction processing support. This compensation from MFD is not reflected in the “Fees and Expenses” table in the fund’s prospectus. MFD compensates financial intermediaries based on criteria established by MFD from time to time, including the distribution potential of the financial intermediary, the types of products and programs offered by the financial intermediary, eligibility for placement on the financial intermediary’s preferred or recommended list, the financial and contractual terms with the financial intermediary, the level and/or type of marketing and administrative support provided by the financial intermediary, and the quality of the overall relationship with the financial intermediary. In particular, MFD normally considers the level of assets attributable to the financial intermediary, the level of redemptions by the financial intermediary, the level of access to the financial intermediary’s representatives and management, the ability to educate the representatives of the financial intermediary about the MFS funds, and the number of representatives of the financial intermediary potentially utilizing the MFS funds with their clients.

MFD makes these additional payments to financial intermediaries for marketing support and administrative services with respect to fund shares sold or held through the financial intermediary’s distribution network and/or through programs such as retirement programs, qualified tuition programs, fund supermarkets, fee-based advisory or wrap fee programs, bank trust programs, and insurance (e.g., individual or group annuity) programs. MFD also makes payments to certain financial intermediaries to help offset the costs associated with client account maintenance support, statement preparation, and transaction processing. To the extent permitted by U.S. Securities and Exchange Commission (SEC) and Financial Industry Regulatory Authority (FINRA) rules and other applicable laws and regulations, MFD makes other payments or allows other promotional incentives or payments to financial intermediaries.

The types of payments described above are not exclusive and such payments can be significant to the financial intermediary. In addition, the compensation that financial intermediaries receive may vary by class of shares sold and among financial intermediaries. Depending upon the arrangements in place at any particular time, financial intermediaries may have a financial incentive to recommend a particular fund or share class when a less expensive option with the same or similar characteristics is available or to recommend MFS funds instead of other funds that generate less or no compensation for the financial intermediary. Likewise, such compensation could create incentives for the financial intermediary to hold an investment longer than might be appropriate, or conversely, to make more frequent exchanges or other transactions than might be necessary.

You can find further details in the SAI about the payments made by MFD and its affiliates and the services provided by financial intermediaries. Financial intermediaries may charge you additional fees and/or commissions other than those disclosed in this prospectus. You should ask your financial intermediary for information about any payments it receives from MFD and its affiliates and any services it provides, as well as about fees and/or commissions it charges you. Financial intermediaries that sell fund shares may also act as a broker/dealer in connection with an MFS fund’s purchase or sale of portfolio securities. However, the fund and MFS do not consider financial intermediaries’ sales of shares of an MFS fund as a factor when choosing broker/dealers to effect portfolio transactions for the MFS funds.

How To Purchase, Redeem, and Exchange Shares

You may purchase, redeem, and exchange shares of the fund in the manner described below. The fund is generally only available to U.S. residents with a valid U.S. tax identification number (and to certain other qualified investors). If you buy or sell shares of a fund through a retirement account, Section 529 tuition plan, or financial intermediary, the procedures for buying, selling, and exchanging shares of the fund and the features, policies, and fees may differ from those discussed in this prospectus. Investment minimums may be waived or reduced for certain types of investors and investments and your financial intermediary may have additional minimums.

How to Purchase Shares

Your shares will be bought at the net asset value per share next calculated after your purchase order is received in proper form. Your financial intermediary is responsible for transmitting your purchase order to the fund in proper form and in a timely manner. MFSC reserves the right to reject any purchase order that is not in proper form. The specific requirements for proper form depend on the type of account and transaction and the method of purchase; contact MFSC if you have questions about your particular circumstances. Certain restrictions apply to the use of a transfer on death registration. You or your financial intermediary should contact MFSC to obtain a Transfer on Death registration form and for information regarding MFSC’s other requirements for transfer on death registrations. If payment for a purchase order is not received by the time required under applicable law, your purchase

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order may be cancelled and your financial intermediary could be liable for any costs or losses.

The fund may reject for any reason, or cancel as permitted or required by law, any purchase orders. The fund may stop offering shares completely, or may offer shares only on a limited basis, for a period of time or permanently.

The fund is required by law to obtain from you certain information that will be used to verify the identity of the account owner. If you do not provide the information, the fund will not be able to open your account. The fund must also take certain steps to verify that the account information you provide is correct.

The fund reserves the right to modify or limit the above exceptions or re-open the fund at any time without prior notice.

Class A, Class B, and Class C Shares. You can establish an account by having your financial intermediary process your purchase or by contacting MFSC directly.

Purchases of Class B shares are subject to a total account value limitation at the time of purchase of $99,999, and purchases of Class C shares are subject to a total account value limitation at the time of purchase of $999,999. If your existing accounts for all share classes held with the MFS funds have a total value equal to $99,999 for Class B share purchases or $999,999 for Class C share purchases, you will not be able to purchase Class B or Class C shares, as applicable. For the purpose of determining your total account value, existing accounts for all share classes held with the MFS funds that are linked under a Letter of Intent or Right of Accumulation will be included.

The fund or its agents may at their discretion accept a purchase request for Class B shares or Class C shares that would otherwise exceed the total account value limitation of $99,999 and $999,999, respectively, under certain circumstances, including purchases by certain types of group or sponsored retirement plans.

Class I Shares. You can establish an account through your MFD representative, by having your financial intermediary process your purchase, or by contacting MFSC directly.

Class R1, Class R2, Class R3, Class R4, and Class R6 Shares. You can establish an account through your financial intermediary or by contacting MFSC directly. For Class R6 investors, you can also establish your account through your MFD representative.

Additional Purchases

You may purchase additional shares through your financial intermediary or MFSC.

Additional Purchases Directly Through MFSC.

	●	Mail. You may purchase additional shares by mailing a check with your investment instructions to MFSC.
	●	Telephone. You may purchase additional shares by phone from your pre-designated bank account. You must elect this privilege on your account application or service application. Purchases via telephone are not available for certain types of accounts.
	●	Internet. You may purchase additional shares from a pre-designated bank account via the Internet at mfs.com (MFS Access). You must elect this privilege on your account application or service application and establish a password on MFS Access to use this service. Purchases via the Internet are not available for Class R1, Class R2, Class R3, Class R4, and Class R6 shares, and certain types of accounts.
	●	Wire. To purchase additional shares by wire, call MFSC for instructions.
	●	Automatic Investment Plan. You may purchase additional shares by automatically investing a designated amount from your checking or savings account on any day of the month. You must elect this privilege on your account application or service application.

Additional Purchases Through Your Financial Intermediary. You can have your financial intermediary purchase shares on your behalf. Your financial intermediary will be responsible for furnishing all necessary documents to MFSC and may charge you for this service.

How to Redeem Shares

Your shares will be sold at the net asset value per share next calculated after your redemption order is received in proper form, minus any applicable CDSC and/or other fees. Your financial intermediary is responsible for transmitting your redemption order

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to the fund in proper form and in a timely manner. MFSC reserves the right to reject any redemption request that is not in proper form. The specific requirements for proper form depend on the type of account and transaction and the method of redemption; contact MFSC if you have questions about your particular circumstances.

In certain circumstances, you will need to have your signature guaranteed and/or submit additional documentation to redeem your shares. In general, no signature guarantee is required for a redemption order for up to $100,000 that is signed by all owners or fiduciaries identified in the account registration, paid as registered, and mailed to the address of record. However, if you have changed your address of record within 30 days of your redemption order, a Medallion signature guarantee will generally be required. A Medallion signature guarantee will also generally be required if you want to send your redemption proceeds to a pre-designated bank account that was added or changed on your account within 30 days of your redemption order.

The fund typically processes your redemption proceeds, after your request is received in proper form, by the end of the next business day for payment by wire and payment processed through DTCC’s Defined Contribution Clearance & Settlement System or Fund/SERV system (financial intermediaries can choose to have payments processed through the Fund/SERV system by the end of the second business day instead of the next business day), and by the end of the second business day for payment by check and Automated Clearing House. However, the fund may delay processing your redemption request for up to seven days. Under unusual circumstances, such as when the NYSE is closed, trading on the NYSE is restricted, or as permitted by the SEC, the fund may suspend redemptions or postpone payment for more than seven days.

If you recently purchased shares and subsequently request a redemption, redemption proceeds (other than in an exchange) for the shares you recently purchased will generally be delayed until money from such purchases sufficient to cover your redemption has been received and collected. Receiving and collecting payment can take up to seven business days after a purchase. You can avoid this delay by purchasing shares by wire transfer.

The fund typically expects to meet redemption requests by holding cash and/or cash equivalents, selling investments, and using overdraft provisions or lines of credit. The fund may also meet redemption requests by redeeming shares in kind for large redemptions or during stressed market conditions. If, during any 90-day period, you redeem shares in an amount greater than the lesser of $250,000 or 1% of fund net assets, and if MFS determines it to be feasible and appropriate, the fund may pay the redemption amount above such threshold by a distribution in kind of portfolio securities (redemption in kind). In the event that the fund makes a redemption in kind, you should expect to incur brokerage and other transaction charges when converting the securities to cash, and the securities will likely increase or decrease in value before you sell them.

You may redeem your shares either by having your financial intermediary process your redemption or by contacting MFSC directly.

Redeeming Directly Through MFSC.

	●	Mail. To redeem shares by mail, you can send a letter, or the applicable redemption form, to MFSC with the name of the fund, your account number, and the number of shares or dollar amount to be redeemed. MFSC currently charges a fee to send your proceeds via overnight mail.
	●	Telephone. If a signature guarantee is not required, you can call MFSC to have shares redeemed from your account and proceeds mailed to the address of record on the account. MFSC currently charges a fee to send your proceeds via overnight mail. You can also call MFSC to have shares redeemed from your account and the proceeds sent directly to a pre-designated bank account. You must elect this privilege on your account application or service application if you wish to have proceeds sent to your bank account. Telephone redemptions are not available for certain types of accounts.
	●	Internet. If a signature guarantee is not required, you can have shares redeemed from your account via the Internet at mfs.com (MFS Access) and the proceeds mailed to the address of record on the account. You can also have shares redeemed from your account via MFS Access and the proceeds sent directly to a pre-designated bank account. You must elect this privilege on your account application or service application and establish a password on MFS Access to use this service. Redemptions via the Internet are not available for Class R1, Class R2, Class R3, Class R4, and Class R6 shares, and certain types of accounts.
	●	Systematic Withdrawal Plan (not available for Class R1, Class R2, Class R3, Class R4, and Class R6 shares). If you have a balance of at least $5,000 in your account in the fund, you may elect to automatically receive (or designate someone else to receive) regular periodic payments (of at least $50 if by check) through an automatic redemption of such classes. The fund may terminate any Systematic Withdrawal Plan for an account if the value of the account falls below $5,000 as a result of share redemptions (other than as a result of a Systematic Withdrawal Plan). Please contact MFSC or your financial intermediary for details.
	●	Checkwriting. You may redeem your Class A and Class C shares by writing checks against your account. There is no charge for this service. You must elect this privilege on your account application to use this service. Shares in your account equal in value to the amount of the check plus the applicable CDSC (if any) and any income tax required to be withheld (if any), are redeemed to cover the amount of the check. If your account value is not great enough to cover these amounts, your check will be dishonored. Checkwriting is not available for all accounts.

Redeeming Through Your Financial Intermediary. You can have your financial intermediary process a redemption on your behalf. Your financial intermediary will be responsible for furnishing all necessary documents to MFSC and may charge you for this service.

Signature Guarantee/Additional Documentation. If a Medallion signature guarantee is required, your signature may be guaranteed by an eligible bank, broker/dealer, credit union, national securities exchange, registered securities association, clearing agency, or savings association that participates in a Medallion program recognized by the Securities Transfer Association. MFSC may require additional documentation for certain types of registrations and under certain circumstances. Signature guarantees and this additional documentation shall be accepted in accordance with policies established by MFSC, and MFSC may, at its discretion, change and make certain exceptions to these requirements. Please

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contact MFSC with any questions and for the requirements for your particular situation.

Share Certificates. If certificates are outstanding for your shares, you may only redeem such shares by mailing the certificates to MFSC. Telephone, electronic, and systematic withdrawal plan redemptions and checkwriting are not available if certificates are outstanding for your shares.

Involuntary Redemptions. Because it is costly to maintain small accounts, the MFS funds have reserved the right to redeem your Class A, Class B, Class C, or Class I shares without your permission when your account contains less than $500 for any reason, including market fluctuation. Before the fund makes such a redemption, you will be notified and given 60 days to increase your investment to at least $500. Certain accounts are not subject to these provisions. Any applicable CDSC will be waived for shares redeemed due to the small size of a shareholder’s account.

In addition, the MFS funds have reserved the right to redeem your shares without your permission in cases of threatening conduct or suspicious, fraudulent, or illegal activity. Any applicable CDSC will be assessed upon redemption of your shares.

How to Exchange Shares

An exchange involves the redemption of shares of one fund and the purchase of shares of another fund.

Exchange Privilege. You can exchange your shares for shares of the same class, if available, of most other MFS funds at their respective net asset values by having your financial intermediary process your exchange request or by contacting MFSC directly. If you exchange Class A shares out of the fund into Class A shares of any other MFS fund, you will pay the initial sales charge, if applicable, if you have not already paid this charge on these shares. You will not pay this initial sales charge if:

	●	the shares of the fund were acquired by an exchange from any other MFS fund;
	●	the shares exchanged from the fund were acquired by automatic investment of distributions from any other MFS fund; or
	●	the shares being exchanged would have, at the time of purchase, been eligible for purchase at net asset value had you invested directly in the MFS fund into which the exchange is being made.

You can exchange your Class A shares and your Class I shares of the fund for shares of the MFS U.S. Government Money Market Fund, if available, according to the terms of such fund’s prospectus.

Shares otherwise subject to a CDSC will not be charged a CDSC in an exchange. Shares will retain the CDSC schedule in effect based upon a pro rata share of the CDSC from the exchanged fund and the original purchase date of the shares subject to the CDSC.

Other funds may have different exchange restrictions. You should read the prospectus of the MFS fund into which you are exchanging and consider the differences in investment objectives, policies, and risks, and in fees and expenses, before making an exchange. The exchange privilege may be changed or discontinued at any time, and all exchanges are subject to certain limitations and MFS funds’ policies concerning disruptive trading practices, which are designed to protect the funds and their shareholders from the harmful effects of frequent trading.

The MFS funds allow certain financial intermediaries to place exchange orders on behalf of a group of their discretionary investment advisory clients (“group exchange orders”). As with any exchange request, the funds and their agents reserve the right to reject any group exchange order, and the funds’ agents will generally reject any group exchange order received by the funds or their agents after 1 p.m., Eastern time. In addition, MFD has agreements with certain financial intermediaries which set forth the terms and conditions under which group exchange orders may be placed by these financial intermediaries. These conditions may be more restrictive than those applicable to individual exchange orders, and may include the requirement to provide the funds or their agents with advance notice of group exchange orders.

Automatic Exchange Plan (not available for Class R1, Class R2, Class R3, Class R4, and Class R6 shares). If you have a balance of at least $2,000 in your account in the fund, you may participate in the automatic exchange plan, a dollar-cost averaging program. This plan permits you to make automatic periodic exchanges from your account in the fund for shares of the same class of other MFS funds. Exchanges will generally be made at net asset value without any sales charges; however, you will pay the initial sales charge, if applicable, if you have not already paid this charge on these shares.

Frequent Trading

General Purchase and Exchange Limitation Policy. The fund reserves the right to restrict, reject, or cancel, without any prior notice, any purchase or exchange order. MFS anticipates that shareholders will purchase and sell shares of the fund frequently because the fund is intended to serve as a liquid cash investment. As a result, the Board of Trustees of the fund has not adopted policies and procedures designed to discourage frequent fund share transactions.

Frequent Trading Risks. To the extent that there are large or frequent purchases and/or redemptions in the fund, these purchases and/or redemptions can interfere with the efficient management of the fund’s portfolio, may result in increased transaction and administrative costs, and may adversely impact the fund’s performance.

Other Considerations

Unauthorized Transactions. MFS will not be responsible for losses that result from unauthorized transactions unless MFSC does not follow procedures reasonably designed to verify your identity. If an account has more than one owner or authorized person, MFSC will accept telephone and online instructions from any one owner or authorized person, except MFSC will require instructions for a redemption from all trustees of trust accounts registered with multiple trustees. It is important that you contact MFSC immediately about any transactions made through MFSC you believe to be unauthorized.

Ability to Contact MFSC. Certain methods of contacting MFSC, such as by mail, telephone, or electronically, may be unavailable or delayed (for example, after natural disasters, during periods of significant/major political, social, or economic instability, or in the event of a cybersecurity incident).

Unclaimed Accounts and Uncashed Checks. If your account has no activity for a certain period of time and/or mail sent to you on behalf of the fund is returned by the post office, the fund may be required to transfer your account and any assets related to uncashed checks to the appropriate state under the state’s abandoned property laws. To avoid such action, it is important to keep your account address up to date and periodically communicate with the fund, MFSC, or your financial intermediary. When a traditional IRA account is transferred to a state as abandoned property, the Internal Revenue Service considers the transfer a taxable distribution subject to federal income tax withholding and reporting. The fund and MFSC will not be liable to shareholders or their representatives for good faith compliance with abandoned property laws.

MFS U.S. Government Cash Reserve Fund

Reservation of Other Rights. In addition to the rights expressly stated elsewhere in this prospectus, subject to applicable rules, laws, and regulations, MFSC reserves the right to: 1) alter, add, or discontinue any conditions of purchase, redemption, service, or privilege at any time without notice; 2) freeze any account or suspend account services when MFSC has received reasonable notice (written or otherwise) of a dispute between registered or beneficial account owners or when MFSC believes a fraudulent transaction may occur or has occurred; and 3) change, impose, discontinue, or waive any fee it charges.

Anti-Money Laundering Restrictions. Federal law requires the fund to implement policies and procedures reasonably designed to prevent, detect and report money laundering and other illegal activity. The fund, consistent with applicable federal law, may redeem your shares and close your account; suspend, restrict or cancel purchase and redemption orders; process redemption requests and withhold your proceeds; and take other action if it is unable to verify your identity within a reasonable time or conduct required due diligence on your account or as otherwise permitted by its anti-money laundering policies and procedures. Any applicable CDSC will be assessed upon redemption of your shares.

Confirmations in Quarterly Statements. Transactions made under certain periodic investment and withdrawal programs (including reinvestment plans) will be confirmed on quarterly account statements.

Other Information

Valuation

The price of each class of the fund’s shares is based on its net asset value. The net asset value of each class of shares is determined each day the NYSE is open for trading as of the close of regular trading on the NYSE (generally 4:00 p.m. Eastern time). However, net asset value may be calculated earlier in emergency situations or as otherwise permitted by the SEC. Net asset value per share is computed by dividing the net assets allocated to each share class by the number of shares outstanding for that class. On days when the NYSE is closed (such as weekends and holidays), net asset value is not calculated, and the fund does not transact purchase and redemption orders. To the extent the fund’s assets are traded in other markets on days when the fund does not price its shares, the value of the fund’s assets will likely change when you will not be able to purchase or redeem shares of the fund.

To determine net asset value, the fund’s investments are generally valued at amortized cost, although in some circumstances the fund’s investments may be valued using available market quotations.

A low or negative interest rate environment could impact the fund’s ability to maintain a stable $1.00 per share. If this occurs, the fund’s Board of Trustees may enact certain measures to seek to maintain a stable $1.00 per share, including the implementation of reverse distributions, reverse stock splits, negative dividends, or other mechanisms, as necessary in the Board’s judgment. Investments in the fund are subject to the potential that the fund’s Board of Trustees may enact such measures.

In a reverse distribution, the fund would reduce the number of shares outstanding in an amount necessary to offset the daily negative income accrued by the fund on its investments. As a result, the number of shares held by each shareholder of the fund would be reduced on a pro rata basis. Although the fund would continue to maintain a stable $1.00 per share, the value of your investment in the fund would decline.

Distributions

The fund intends to declare a dividend daily and to pay any dividends to shareholders at least monthly.

Any capital gains are distributed at least annually.

Distribution Options

The following distribution options are generally available for Class A, Class B, Class C, and Class I shares:

	●	Dividend and capital gain distributions automatically reinvested in additional shares (this option will be assigned if no other option is specified);
	●	Dividend distributions in cash; capital gain distributions automatically reinvested in additional shares;
	●	Dividend and capital gain distributions in cash; or
	●	Dividend and capital gain distributions automatically reinvested into the same class of shares of another MFS fund (not available for Class B shares).

Not all options are available for every class or every account.

Dividends and capital gain distributions for Class R1, Class R2, Class R3, Class R4, and Class R6 shares can only be reinvested in additional shares of the fund, except with respect to Class R6 shares, (i) certain institutional shareholders, (ii) shareholders who purchase shares through brokerage programs of certain financial intermediaries, and (iii) shareholders who purchase shares through asset-based fee programs of certain financial intermediaries may elect any of the other distribution options described above.

The distribution option for accounts with dividend distributions of less than $10 generally will be changed to reinvestment in additional shares of the fund. If you have elected to receive distributions in cash, and the postal service is unable to deliver checks to your address of record, or you do not respond to mailings from MFSC with regard to uncashed distribution checks, your distribution option may be converted to having all distributions reinvested in additional shares. You should contact MFSC to change your distribution option, and your request to do so must be received by MFSC before the record date for a distribution in order to be effective for that distribution. No interest will accrue on amounts represented by uncashed distribution checks.

Tax Considerations

The following discussion is very general. You are urged to consult your tax adviser regarding the effect that an investment in the fund will have on your particular tax situation, including possible foreign, state, and local taxes. This discussion does not apply to shares of the fund held through tax-advantaged accounts or by shareholders that are not “U.S. persons” under the Internal Revenue Code of 1986, as amended.

The fund expects to distribute substantially all of its income and gains annually. The fund expects that substantially all its distributions will consist of investment income. Distributions from the fund are taxable whether you receive them in cash or reinvest them in additional shares.

For federal income tax purposes, distributions of investment income are generally taxable as ordinary income.

Distributions designated as capital gain dividends are taxable as long-term capital gains includible in net capital gain and taxed to individuals at reduced rates.

Any gain resulting from the redemption, sale, or exchange of your shares will generally also be subject to tax.

A 3.8% Medicare contribution tax is generally imposed on

MFS U.S. Government Cash Reserve Fund

distributions paid by the fund (other than exempt-interest dividends, if any) to, and net gains recognized on the sale, redemption, exchange, or other taxable disposition of shares of the fund by certain individuals, estates, and trusts to the extent their income exceeds certain threshold amounts.

The fund’s investments in foreign securities may be subject to foreign withholding or other taxes, which will decrease the fund’s return on those securities; you generally are not expected to be eligible to claim a credit (or a deduction) for such amounts on your federal income tax return.

The Form 1099 that is provided to you early each year details your distributions from the fund and how they are treated for federal tax purposes, and cost basis information for shares purchased on or after January 1, 2012, that you redeemed, sold, or exchanged. Our default method for calculating cost basis is average cost basis. More information about other cost basis methods and a cost basis selection/change form are available on mfs.com. If your account is held by your financial intermediary, you must contact your financial intermediary to obtain information about available cost basis methods and cost basis elections for your account.

Information about the Summary Prospectus, Prospectus, and SAI

The summary prospectus, prospectus, and SAI for a fund provide information concerning the fund. The summary prospectus, prospectus, and SAI are updated at least annually and any information provided in a summary prospectus, prospectus, or SAI can be changed without a shareholder vote unless specifically stated otherwise. The summary prospectus, prospectus, and SAI are not contracts between the fund and its shareholders and do not give rise to any contractual rights or obligations or any shareholder rights other than any rights conferred explicitly by federal or state securities laws that may not be waived.

Provision of Financial Reports and Summary Prospectuses

The fund produces financial reports every six months and updates its summary prospectus and prospectus annually. To avoid sending duplicate copies of materials to households, only one paper copy of the fund’s annual and semiannual report and summary prospectus may be mailed to shareholders having the same last name and residential address on the fund’s records. However, any shareholder may contact MFSC (please see back cover for address and telephone number) to request that copies of these reports and summary prospectuses be sent personally to that shareholder.

Additional Information on Fees and Expenses and Performance

Fees and Expenses

The annual fund operating expenses shown in “Fees and Expenses” are based on annualized expenses reported during the fund’s most recently completed fiscal year expressed as a percentage of a class’ average net assets during the period. Annual fund operating expenses have not been adjusted to reflect the fund’s current asset size. In general, annual fund operating expenses, expressed as a percentage of a class’ average net assets, increase as the fund’s assets decrease. Annual fund operating expenses will likely vary from year to year.

Performance Information

All performance information shown in the “Class A Bar Chart” and the “Performance Table” reflects any applicable fee reductions and waivers and expense reimbursements in effect during the periods shown; without these, the performance would have been lower.

From time to time, the fund may receive proceeds from litigation settlements, without which performance would be lower.

The fund commenced operations on December 29, 1986, with the offering of Class B shares, and subsequently offered Class A shares on September 7, 1993, Class C shares on April 1, 1996, and Class R1, Class R2, Class R3, and Class R4 shares on April 1, 2005, and Class I shares and Class R6 shares on September 18, 2018.

In the “Performance Table,” performance for each of Class I and Class R6 shares includes the performance of the fund’s Class A shares, adjusted to take into account differences in sales loads and class specific operating expenses (such as Rule 12b-1 fees), if any, for periods prior to their offering.

MFS U.S. Government Cash Reserve Fund

Financial Highlights

The financial highlights are intended to help you understand a fund’s financial performance for the past five years (or life of a particular class, if shorter). Certain information reflects financial results for a single fund share. The total returns in the financial highlights represent the rate by which an investor would have earned (or lost) on an investment in a fund (assuming reinvestment of all distributions) held for the entire period. This information has been audited by the fund’s independent registered public accounting firm, whose report, together with the fund’s financial statements, is included in the fund’s Annual Report to shareholders. The fund’s Annual Report is available upon request by contacting MFSC (please see back cover for address and telephone number). The fund’s independent registered public accounting firm is Deloitte & Touche LLP.

Class A

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.83			0.28			0.00			0.54			1.58
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		0.83			0.91			0.91			0.96			0.98
Expenses after expense reductions		0.43			0.21			0.05			0.44			0.72
Net investment income (loss)		3.74			0.33			0.00			0.44			1.57
Net assets at end of period (000 omitted)	$	161,677		$	173,514		$	128,482		$	140,426		$	99,511

Class B

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.83			0.28			0.00			0.54			1.58
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		1.58			1.66			1.66			1.71			1.73
Expenses after expense reductions		0.43			0.18			0.05			0.47			0.72
Net investment income (loss)		3.68			0.25			0.00			0.49			1.57
Net assets at end of period (000 omitted)	$	3,501		$	5,194		$	6,792		$	9,528		$	8,977

MFS U.S. Government Cash Reserve Fund

Class C

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.83			0.28			0.00			0.54			1.58
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		1.58			1.66			1.66			1.71			1.73
Expenses after expense reductions		0.43			0.25			0.05			0.40			0.72
Net investment income (loss)		3.56			0.40			0.00			0.37			1.57
Net assets at end of period (000 omitted)	$	22,344		$	43,674		$	23,748		$	34,508		$	19,438

Class I

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19(i)
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.83			0.28			0.00			0.54			1.52	(n)
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		0.58			0.66			0.65			0.69			0.73	(a)
Expenses after expense reductions		0.43			0.20			0.05			0.23			0.72	(a)
Net investment income (loss)		3.75			0.29			0.00			0.06			1.60	(a)
Net assets at end of period (000 omitted)	$	17,492		$	17,382		$	12,819		$	9,797		$	56

MFS U.S. Government Cash Reserve Fund

Class R1

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.82			0.28			0.00			0.54			1.57
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		1.58			1.66			1.65			1.71			1.73
Expenses after expense reductions		0.43			0.19			0.05			0.47			0.72
Net investment income (loss)		3.70			0.27			0.00			0.48			1.57
Net assets at end of period (000 omitted)	$	6,818		$	9,298		$	8,761		$	9,209		$	7,610

Class R2

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.01		$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.01		$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.01	)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.01	)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.82			0.28			0.00			0.54			1.57
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		1.08			1.16			1.16			1.21			1.23
Expenses after expense reductions		0.43			0.19			0.05			0.48			0.72
Net investment income (loss)		3.67			0.26			0.00			0.51			1.57
Net assets at end of period (000 omitted)	$	17,342		$	23,726		$	26,432		$	33,676		$	31,672

MFS U.S. Government Cash Reserve Fund

Class R3

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.82			0.28			0.00			0.54			1.57
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		0.83			0.91			0.90			0.96			0.98
Expenses after expense reductions		0.43			0.19			0.05			0.44			0.72
Net investment income (loss)		3.74			0.29			0.00			0.44			1.55
Net assets at end of period (000 omitted)	$	19,628		$	21,166		$	21,266		$	24,536		$	16,471

Class R4

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.00	(w)	$	0.00		$	0.01		$	0.02
Net realized and unrealized gain (loss)		—			(0.00	)(w)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.01		$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.01	)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.01	)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.83			0.28			0.00			0.54			1.57
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		0.58			0.66			0.65			0.71			0.73
Expenses after expense reductions		0.43			0.19			0.05			0.49			0.72
Net investment income (loss)		3.77			0.27			0.00			0.54			1.57
Net assets at end of period (000 omitted)	$	2,787		$	2,684		$	2,676		$	2,709		$	2,676

MFS U.S. Government Cash Reserve Fund

Class R6

	Year ended
	8/31/23			8/31/22			8/31/21			8/31/20			8/31/19(i)
Net asset value, beginning of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income (loss) from investment operations
Net investment income (loss) (d)	$	0.04		$	0.01		$	0.00		$	0.00	(w)	$	0.02
Net realized and unrealized gain (loss)		—			(0.01	)		0.00	(w)		0.00	(w)		0.00	(w)
Total from investment operations	$	0.04		$	0.00	(w)	$	0.00	(w)	$	0.00	(w)	$	0.02
Less distributions declared to shareholders
From net investment income	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
From net realized gain		—			(0.00	)(w)		—			—			—
Total distributions declared to shareholders	$	(0.04	)	$	(0.00	)(w)	$	—		$	(0.00	)(w)	$	(0.02	)
Net asset value, end of period	$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total return (%) (r)(t)		3.89			0.30			0.00			0.58			1.58	(n)
Ratios (%) (to average net assets) and Supplemental data:
Expenses before expense reductions		0.53			0.56			0.59			0.65			0.66	(a)
Expenses after expense reductions		0.37			0.37			0.05			0.42			0.65	(a)
Net investment income (loss)		3.85			0.99			0.00			0.46			1.65	(a)
Net assets at end of period (000 omitted)	$	227,118		$	211,381		$	113		$	113		$	54

(a)	Annualized.
(d)	Per share data is based on average shares outstanding.
(i)	For Class I and Class R6, the period is from the class inception, September 18, 2018, through the stated period end.
(n)	Not annualized.
(r)	Certain expenses have been reduced without which performance would have been lower.
(t)	Total returns do not include any applicable sales charges.
(w)	Per share amount was less than $0.01.

MFS U.S. Government Cash Reserve Fund

Appendix A - Waivers and Reductions of Sales Charges

This Appendix sets forth the various circumstances in which the initial sales charge (ISC) and/or the CDSC is waived or reduced for the MFS funds’ share classes. The waivers and reductions that are applicable to your transaction depend on your financial intermediary and the type of account and transaction. Financial intermediaries may have different policies and procedures regarding the availability of ISC or CDSC waivers, which are discussed below. In all instances, it is your responsibility to notify your financial intermediary or MFSC at the time of purchase of any relationship or other facts qualifying you for sales charge waivers or reductions. For waivers and reductions not available through a particular financial intermediary, shareholders will have to purchase fund shares through another financial intermediary or directly from the fund to receive these waivers or reductions. You should contact your financial intermediary or MFSC if you have questions on the waivers and reductions that apply to your account and/or transaction type, including whether your account is maintained at an omnibus level with the fund by your financial intermediary. The following Categories of waivers and reductions apply:

	●	Merrill Lynch (Merrill) – If Merrill is the record owner of your shares and/or broker of record on your account and the account is maintained at an omnibus level by Merrill with the fund, Category II waivers apply.
	●	Ameriprise Financial – If Ameriprise Financial is the record owner and/or broker of record on your account invested in Class A shares and the account is maintained at an omnibus level by Ameriprise Financial with the fund, Category III waivers apply.
	●	Morgan Stanley – If Morgan Stanley is the record owner and/or broker of record on your account invested in Class A shares of the fund and the account is a Morgan Stanley Wealth Management transactional brokerage account maintained at an omnibus level by Morgan Stanley with the fund, Category IV waivers apply.
	●	Raymond James – If you are invested in shares of the fund 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, and the account is maintained at an omnibus level by Raymond James with the fund, Category V waivers apply.
	●	Janney Montgomery Scott LLC (Janney) – If you are invested in shares of the fund through an account maintained at an omnibus level by or on behalf of Janney with the fund, Category VI waivers apply.
	●	Edward Jones – If you are invested in shares of the fund through an Edward Jones platform or account maintained at an omnibus level by Edward Jones with the fund, Category VII waivers apply.
	●	D.A. Davidson & Co. (D.A. Davidson) – If you are invested in shares of the fund through a D.A. Davidson platform or account maintained at an omnibus level by or on behalf of D.A. Davidson with the fund, Category VIII waivers apply.
	●	Baird – If you are invested in shares through a Baird platform or account maintained at an omnibus level by or on behalf of Baird with the fund, Category IX waivers apply.
	●	J.P. Morgan Securities LLC – If you are invested in shares of the fund through an applicable J.P. Morgan Securities LLC brokerage account, Category X waivers apply.
	●	Stifel, Nicolaus & Company, Incorporated (Stifel) – If you are invested in shares of the fund through an applicable Stifel brokerage account, Category XI waivers apply.
	●	All Others – Category I waivers apply to other accounts and transactions that do not otherwise fall under Category II – XI.

Not all MFS funds offer each share class. In order to qualify for a sales charge waiver or reduction, you must advise MFSC or your financial intermediary that you are eligible for the waiver at the time of purchase and/or redemption. The fund, MFS, and their affiliates reserve the right to eliminate, modify, and add waivers and reductions of sales charges at any time at their discretion.

Shares otherwise subject to a CDSC will not be charged a CDSC in an exchange. Shares will retain the CDSC schedule in effect prior to an exchange based upon a pro rata share of the CDSC from the exchanged fund and the original purchase date of the shares subject to the CDSC. If you exchange your shares out of MFS U.S. Government Money Market Fund or MFS U.S. Government Cash Reserve Fund into Class A shares of any other MFS fund, you will pay the initial sales charge, if applicable, if you have not already paid this charge on these shares. You will not pay the initial sales charge if:

	●	the shares exchanged from either MFS fund were acquired by an exchange from any other MFS fund;
	●	the shares exchanged from either MFS fund were acquired by automatic investment of distributions from any other MFS fund; or
	●	the shares being exchanged would have, at the time of purchase, been eligible for purchase at net asset value had you invested directly in the MFS fund into which the exchange is being made.

In addition, transfers, rollovers, or other transactions from an account to a second account that purchases shares of the same class of the same fund or another MFS fund will not be charged the CDSC or ISC, as applicable, provided that the redemption order from the first account and the purchase order for the second account are combined into a single order for the transfer, rollover, or other transaction, and MFSC has available to it the necessary information about the CDSC applicable to the first account. Shares will retain the CDSC schedule in effect based upon a pro rata share of the CDSC from the fund in the first account and the original purchase date of the shares subject to the CDSC. You should contact your financial intermediary or MFSC if you have questions on the sales charge waivers and reductions that apply in a transfer between accounts, including whether MFSC has the required information.

The CDSC may be waived from time to time pursuant to Conduct Rule 2341 of FINRA.

With respect to MFS Municipal Income Fund, all references to Class A shares shall also apply to Class A1 shares and all references to Class B shares shall also apply to Class B1 shares.

A-1

MFS U.S. Government Cash Reserve Fund

WAIVERS AND REDUCTIONS

Financial Intermediary Category I

Eligible Accounts:

Accounts that are not Eligible for Financial Intermediary Categories II – XI

As used below, the term “ESP” refers to employer sponsored plans; the term “SRO” refers to salary reduction only plans; the term “Employer Retirement Plans” includes 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans, defined benefit plans and non-qualified deferred compensation plans any of whose accounts are maintained by the fund at an omnibus level; the term “IRA” refers to traditional, Roth, rollover, SEP and SIMPLE IRAs; the term “ERISA” refers to the Employment Retirement Income Security Act of 1974, as amended.

GENERAL WAIVERS

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
A. Distribution Reinvestment
Shares acquired through dividend or capital gain reinvestment into the same class of the fund.	√	√	√	√
Shares acquired by automatic reinvestment of distributions of dividends and capital gains of any MFS fund into the same class of shares of another MFS fund.	√	√	√	√
B. Affiliates of Funds/Certain Financial Advisers
Shares acquired by officers, eligible directors, employees (including former employees), and agents of MFS, Sun Life Financial, or any of their subsidiary companies.	√	√	√	√
Shares acquired by trustees and former trustees of any investment company for which MFD serves as distributor.	√	√	√	√
Shares acquired by employees, directors, partners, officers, and trustees of any subadvisor to any MFS fund.	√	√	√	√
Shares acquired by certain family members of any such individual identified above and their spouses (or legal equivalent under applicable state law), and certain trusts, pension, profit-sharing or other retirement plans for the sole benefit of such persons, provided the shares are not resold except to the fund which issued the shares.	√	√	√	√
Shares acquired by employees or registered representatives (including former employees) of financial intermediaries that have a selling agreement with MFD or an employee’s spouse (or legal equivalent under applicable state law) or employee’s children under the age of 21. For employees or registered representatives of such financial intermediaries who established an account with MFS prior to May 1, 2006, shares acquired by certain family members of employees or registered representatives of financial intermediaries and their spouses (or legal equivalent under applicable state law), and certain trusts, pension, profit-sharing or other retirement plans for the sole benefit of such persons, provided the shares are not resold except to the fund which issued the shares.	√	√	√	√
Shares acquired by institutional clients of MFS or MFS Institutional Advisors, Inc.	√	√	√	√
C. Involuntary Redemptions
Shares redeemed at a fund’s direction due to the small size of a shareholder’s account.		√	√	√
D. Investment of Proceeds From Certain Redemptions of Class I Shares
The initial sales charge imposed on purchases of Class A shares and the contingent deferred sales charge imposed on certain redemptions of Class A shares, are waived with respect to Class A shares acquired of any MFS fund through the immediate reinvestment of the proceeds of a redemption of Class I shares of any MFS fund.	√	√
E. Systematic Withdrawals
Systematic withdrawals with respect to up to 10% per year of the account value determined at the time of your first withdrawal under the plan(s) (or January 4, 2016, with respect to Class A shares, whichever is later).		√	√	√

A-2

MFS U.S. Government Cash Reserve Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
F. Death of Owner
Shares redeemed on account of the death of the account owner (e.g., shares redeemed by the estate or any transferee of the shares from the estate) if the shares were held solely in the deceased individual’s name, or for the benefit of the deceased individual.		√	√	√
G. Disability of Owner
Shares redeemed on account of the disability of the account owner if shares are held either solely or jointly in the disabled individual’s name or for the benefit of the disabled individual (in which case a disability certification form is required to be submitted to MFSC), or shares redeemed on account of the disability of the 529 account beneficiary.		√	√	√
H. Asset-Based Fee Programs
Shares acquired by investors who purchase shares through asset-based fee programs available through financial intermediaries.	√	√
I. Insurance Company Separate Accounts
Shares acquired by insurance company separate accounts.	√	√
J. No Commissions Paid
Shares redeemed where MFD has not paid an up-front commission with respect to the sale of the shares, provided that such arrangement meets certain conditions established by MFD from time to time.		√	√	√
K. Conversions
In connection with a conversion from Class A shares to Class I shares of the same fund.		√
In connection with a conversion from Class A shares to Class I shares of the same fund as a result of no financial intermediary being specified on the account.		√
In connection with a conversion from Class B shares to Class I shares of the same fund as a result of no financial intermediary being specified on the account.			√
In connection with a conversion from Class C shares to Class I shares of the same fund as a result of no financial intermediary being specified on the account.				√
In connection with a conversion from Class I shares to Class A shares of the same fund.	√	√
In connection with an automatic conversion from Class B shares to Class A shares of the same fund.	√	√
In connection with an automatic conversion from Class C shares to Class A shares of the same fund.	√	√
In connection with a conversion from Class C shares to Class A shares of the same fund if the shareholder’s financial intermediary provides written notification to MFD prior to such conversion that the intermediary has determined that Class A was the appropriate share class at the time of purchase for such shareholder and receives approval of such conversion by MFD.	√	√		√
L. Exchanges
The initial sales charge imposed on purchases of Class A shares is waived on shares purchased pursuant to an Automatic Exchange Plan.	√
The initial sales charge imposed on purchases of Class A shares is waived when shares are purchased by exchange from another MFS fund.	√
M. Reinstatement Privilege
The initial sales charge imposed on purchases of Class A shares is waived when shares are purchased pursuant to the Reinstatement Privilege as described below.	√
N. Large Purchases
The initial sales charge imposed on purchases of Class A shares is waived for purchases in excess of the maximum breakpoint amount described under “Description of Share Classes – Sales Charges and Waivers and Reductions” in the fund’s prospectus. Letter of Intent or Right of Accumulation provisions may apply for purposes of determining purchase amount as described below.	√

A-3

MFS U.S. Government Cash Reserve Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
O. Miscellaneous
In connection with settlements reached between certain broker/dealers and FINRA, the SEC, and/or other regulatory bodies regarding sales of Class B and Class C shares in excess of certain dollar thresholds, the fund will, at times, permit shareholders who are clients of these firms to redeem Class B and Class C shares of the fund and concurrently purchase Class A shares without paying an initial sales charge.	√	√
P. Self-Directed Brokerage Account Platforms (Class A shares only)
Shares acquired through a self-directed brokerage account platform (that may or may not charge a transaction fee to investors) offered by a financial intermediary who has entered into an agreement with MFD to offer fund shares through such platform. As of the date of the fund’s prospectus, the following financial intermediaries had entered into an agreement with MFD to offer fund shares through such a platform: Charles Schwab & Co. Inc.; National Financial Services LLC; Fidelity Brokerage Services LLC; J.P. Morgan Securities LLC; Morgan Stanley Smith Barney LLC; Merrill Lynch, Pierce, Fenner & Smith Incorporated; Nationwide Financial Services, Inc.; GWFS Equities, Inc.; E*TRADE Securities LLC; Nationwide Securities LLC, TD Ameritrade, Inc., and TD Ameritrade Clearing, Inc.	√	√
Q. LPL Mutual Funds Only Platform (Class A shares only)
Shares acquired through the Mutual Fund Only Platform or other similar platform offered by LPL Financial LLC who has entered into an agreement with MFD to offer fund shares through such platform.	√	√
R. U.S. Bancorp Investments, Inc., (USBI) Accounts Maintained at an Omnibus Level (Class A shares only)
Class C shares that are no longer subject to a contingent deferred sales charge are systematically converted to Class A shares of the same fund at net asset value pursuant to USBI’s policies and procedures.	√

WAIVERS FOR Retirement Plans

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
A. General Waivers
Employer Retirement Plans.	√	√
B. Benefit Responsive Waivers
Distributions made from an IRA, SAR-SEP, or a 403(b) SRO Plan pursuant to Section 72(t) of the Internal Revenue Code of 1986, as amended.		√	√	√
Death, disability, or retirement of 401(a) or ESP Plan participant, or death or disability of IRA owner, SAR-SEP Plan participant or 403(b) SRO Plan participant.		√	√	√
Eligible participant distributions, such as distributions due to death, disability, financial hardship, retirement, and termination of employment from nonqualified deferred compensation plans (excluding, however, a termination of a plan).		√	√	√
Loan from 401(a) or ESP Plan.		√	√	√
Financial hardship (as defined in U.S. Treasury Department Regulation Section 1.401(k)-l(d)(2), as amended from time to time) for 401(a) Plans and ESP Plans.		√	√	√
Termination of employment of 401(a) or ESP Plan participant (excluding, however, a termination of the Plan).		√	√	√
Tax-free return of excess 401(a) Plan, ESP Plan, IRA, or SAR-SEP contributions.		√	√	√
Certain involuntary redemptions and redemptions in connection with certain automatic withdrawals from a 401(a) Plan.		√	√	√
Required minimum distributions pursuant to Internal Revenue Code rules made on or after the 401(a) Plan participant, ESP Plan participant, IRA owner, SAR-SEP Plan participant or 403(b) SRO Plan participant, as applicable, has attained the age at which such distributions are required under Internal Revenue Code rules.		√	√	√

A-4

MFS U.S. Government Cash Reserve Fund

Description of Certain Investment Programs Eligible for Sales Charge Waivers or Reductions

Letter Of Intent (LOI). You may pay a reduced or no initial sales charge on purchases of Class A shares if you intend to invest a specific dollar amount, based on the gross amount of your investment (including the amount of any sales charge paid), including investments through any linked accounts in any class of any MFS fund within a 13-month period (36 months for shareholders with an LOI entered into prior to February 1, 2023, with a $1 million commitment) and investments in the MFS 529 Savings Plan. Distributions reinvested in additional shares of the fund or distributions from other MFS funds automatically invested in shares of the fund will not apply toward the satisfaction of the LOI.

For each purchase you make under the LOI you will pay the initial sales charge rate applicable to the total amount you intended to purchase.

Out of the shareholder’s initial purchase (or subsequent purchases if necessary), 5% of the dollar amount specified in the Letter of Intent application shall be held in escrow by MFSC in the form of shares registered in the shareholder’s name. All distributions on escrowed shares will be paid to the shareholder or to the shareholder’s order. At the end of the 13-month period or 36-month period, as applicable, the shareholder will be notified, the escrowed shares will be released, and the Letter of Intent will be terminated.

If the intended minimum investment amount is not completed, MFSC will redeem an appropriate number of the escrowed shares in order to pay the higher sales charge level for the amount actually purchased. Shares remaining after any such redemption will be released by MFSC. By completing and signing the Account Application or separate Service Application, the shareholder irrevocably appoints MFSC his or her attorney to surrender for redemption any or all escrowed shares with full power of substitution in the premises.

To establish an LOI, complete the Letter of Intent section of your account application or service application. In order to benefit from the LOI, it is your responsibility to inform your financial intermediary or MFSC that the LOI is in effect each time shares of a fund are purchased.

Right Of Accumulation (ROA). Under the ROA, you may pay a reduced or no initial sales charge on purchases of Class A shares by aggregating the total dollar amount of your investment with your existing investments or any linked accounts invested in MFS funds and/or any investments in the MFS 529 Savings Plan, based on the current maximum public offering price of the funds. For example, you will pay a sales charge on your current purchase at the rate applicable to the total value of all eligible accounts.

Linking Accounts For LOI and ROA. For purposes of obtaining reduced sales charges under the LOI and ROA, you may combine the value of your accounts with those of your spouse (or legal equivalent under applicable state law) and your children under the age of 21.

Eligible accounts that you may link under an LOI and ROA are:

	●	Individual accounts;
	●	Joint accounts;
	●	Trust accounts of which you, your spouse (or legal equivalent under applicable state law), or child under the age of 21 is the grantor;
	●	Certain single-participant retirement plan accounts;
	●	Certain Individual Retirement Accounts;
	●	Uniform Gifts/Transfers to Minor Acts accounts; and
	●	Accounts held in the name of your financial intermediary on your behalf.

In addition to the accounts set forth above which are eligible for linking, you may also combine any of your investments in the MFS 529 Savings Plan for purposes of obtaining reduced sales charges on purchases of Class A shares of any MFS fund.

It is your responsibility to inform the broker/dealer for each current purchase of any accounts held with the MFS funds that you believe are eligible to be linked under an LOI or an ROA and of any investments you have in the MFS 529 Savings Plan that are also able to be counted for purposes of obtaining reduced sales charges on purchases of Class A shares of any MFS fund. If you have not designated a broker/dealer, you should inform MFSC directly of any accounts held with the MFS funds and of any investments in the MFS 529 Savings Plan that you believe are eligible to be counted under an LOI or an ROA. You should provide your financial intermediary (or MFSC if you have not designated a broker/dealer) with certain supporting information at the time of each purchase regarding accounts held with the MFS funds and investments in the MFS 529 Savings Plan that are eligible to be combined for purposes of an LOI or ROA. Such information may include shareholder identification numbers or applicable account numbers or account statements. Your financial intermediary is responsible for taking into account this information about accounts eligible to be combined (including any MFS 529 Savings Plan investments) when transmitting your purchase order to the fund.

Group Purchases. A bona fide group and all its members may be treated at MFD’s discretion as a single purchaser and, under the ROA (but not the LOI), obtain quantity sales charge discounts on the purchase of Class A or Class A1 shares if the group (1) gives its endorsement or authorization to the investment program so that it may be used by the financial intermediary to facilitate solicitation of the membership, thus effecting economies of the sales efforts; (2) has a legitimate purpose other than to purchase mutual fund shares at a discount; (3) is not a group of individuals whose sole organizational nexus is as credit cardholders of a company, policyholders of an insurance company, customers of a bank or financial intermediary, clients of an investment adviser, or other similar groups; and (4) agrees to provide certification of membership of those members investing money in the funds upon the request of MFD. Employer-sponsored retirement plans, such as a 401(a) plan, 457 deferred compensation plan, an Employer Sponsored Group IRA, and an IRA SEP/SARSEP, SIMPLE and 403(b) plans, may qualify as a bona fide group if they meet the above criteria.

A-5

MFS U.S. Government Cash Reserve Fund

Reinstatement Privilege. With respect to Class A, Class B and Class C shares, after you have redeemed fund shares, you have a one-time right per fund per registration to reinvest the proceeds in the fund within 90 days of the redemption without paying a sales charge. Proceeds can only be reinvested in Class A shares of the same fund under the same account registration.

Any CDSC paid upon the redemption of Class A shares will be credited to your account, and your new Class A shares will be subject to a CDSC according to the CDSC schedule applicable to your original shares.

Any CDSC paid upon the redemption of Class B or Class C shares will not be credited to your account.

In order to benefit from the reinstatement privilege, it is your responsibility to inform your financial intermediary or MFSC that the reinstatement privilege is in effect each time shares of the fund are purchased under this privilege.

A-6

MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category II

Eligible Accounts:

Accounts with Merrill Listed as Record Owner and/or Broker of Record and Which Are Maintained at an Omnibus Level by Merrill with the Fund

Purchases or sales of front-end (i.e., Class A) or level-load (i.e., Class C) mutual fund shares through a Merrill platform or account will be eligible only for the following sales load waivers (front-end, contingent deferred, or back-end waivers) and discounts, which differ from those disclosed elsewhere in this Fund’s prospectus. Purchasers will have to buy mutual fund shares directly from the mutual fund company or through another intermediary to be eligible for waivers or discounts not listed below.

It is the client’s responsibility to notify Merrill at the time of purchase or sale of any relationship or other facts that qualify the transaction for a waiver or discount. A Merrill representative may ask for reasonable documentation of such facts and Merrill may condition the granting of a waiver or discount on the timely receipt of such documentation.

Additional information on waivers and discounts is available in the Merrill Sales Load Waiver and Discounts Supplement (the “Merrill SLWD Supplement”) and in the Mutual Fund Investing at Merrill pamphlet at ml.com/funds. Clients are encouraged to review these documents and speak with their financial advisor to determine whether a transaction is eligible for a waiver or discount.

Front-end Load Waivers Available at Merrill

Shares of mutual funds available for purchase by employer-sponsored retirement, deferred compensation, and employee benefit plans (including health savings accounts) and trusts used to fund those plans provided the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan. For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans

Shares purchased through a Merrill investment advisory program

Brokerage class shares exchanged from advisory class shares due to the holdings moving from a Merrill investment advisory program to a Merrill brokerage account

Shares purchased through the Merrill Edge Self-Directed platform

Shares purchased through the systematic reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same mutual fund in the same account

Shares exchanged from level-load shares to front-end load shares of the same mutual fund in accordance with the description in the Merrill SLWD Supplement

Shares exchanged from back-end load (i.e., Class B) shares to front-end load shares of the same mutual fund¹

Shares purchased by eligible employees of Merrill or its affiliates and their family members who purchase shares in accounts within the employee’s Merrill Household (as defined in the Merrill SLWD Supplement)

Shares purchased by eligible persons associated with the fund as defined in this prospectus (e.g., the fund’s officers or trustees)

Shares purchased from the proceeds of a mutual fund redemption in front-end or back-end load shares provided (1) the repurchase is in a mutual fund within the same fund family; (2) the repurchase occurs within 90 calendar days from the redemption trade date, and (3) the redemption and purchase occur in the same account (known as Rights of Reinstatement). Automated transactions (i.e., systematic purchases and withdrawals) and purchases made after shares are automatically sold to pay Merrill’s account maintenance fees are not eligible for Rights of Reinstatement

Contingent Deferred Sales Charge (“CDSC”) Waivers on Front-end, Back-end, and Level Load Shares Available at Merrill

Shares sold due to the client’s death or disability (as defined by Internal Revenue Code Section 22e(3))

Shares sold pursuant to a systematic withdrawal program subject to Merrill’s maximum systematic withdrawal limits as described in the Merrill SLWD Supplement

Shares sold 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 investor reaching the qualified age based on applicable IRS regulation

Shares exchanged from back-end load shares to front-end load shares of the same mutual fund¹

Front-end or level-load shares held in commission-based, non-taxable retirement brokerage accounts (e.g., traditional, Roth, rollover, SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans) that are transferred to fee-based accounts or platforms and exchanged for a lower cost share class of the same mutual fund

On or around April 15, 2024, Merrill will exchange all back-end load shares held in Merrill accounts to front-end load shares of the same mutual fund.

A-7

MFS U.S. Government Cash Reserve Fund

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

Breakpoint discounts, as described in this prospectus, where the sales load is at or below the maximum sales load that Merrill permits to be assessed to a front-end load purchase, as described in the Merrill SLWD Supplement

Rights of Accumulation (ROA), as described in the Merrill SLWD Supplement, which entitle clients to breakpoint discounts based on the aggregated holdings of mutual fund family assets held in accounts in their Merrill Household

Letters of Intent (LOI), which allow for breakpoint discounts on eligible new purchases based on anticipated future eligible purchases within a fund family at Merrill, in accounts within your Merrill Household, as further described in the Merrill SLWD Supplement

A-8

MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category III

Eligible Accounts:

Accounts Investing in Class A Shares with Ameriprise Financial Listed as Record Owner and/or Broker of Record and Which Are Maintained at an Omnibus Level by Ameriprise Financial with the Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC
A. Distribution Reinvestment
Shares acquired through dividend or capital gain reinvestment into the same class of the fund.	√	√
B. Employees/Registered Representatives of Ameriprise Financial
Shares purchased by 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 financial adviser and/or the adviser’s spouse, adviser’s lineal ascendant (mother, father, grandmother, grandfather, great grandmother, great grandfather), adviser’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.	√	√
C. Reinstatement Privilege
Shares purchased from the proceeds of redemptions within the same fund family, provided (i) the repurchase occurs within 90 days following the redemption, (ii) the redemption and purchase occur in the same account, and (iii) redeemed shares were subject to a front-end or deferred sales charge.	√	√
D. Retirement Plans
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.	√	√
E. Transactions between Share Classes
Shares exchanged from Class C shares of the same fund in the month of or following the 7-year anniversary of the purchase date. To the extent that the fund’s prospectus elsewhere provides for a waiver with respect to exchanges of Class C shares or conversion of Class C shares following a shorter holding period, that waiver will apply. To the extent that the fund’s prospectus elsewhere provides for a waiver with respect to exchanges of Class C shares for load-waived shares, that waiver will also apply to such exchanges.	√	√

Description of Certain Investment Programs Eligible for Sales Charge Waivers or Reductions

Letter Of Intent (LOI). You may pay a reduced or no initial sales charge on purchases of Class A shares if you intend to invest a specific dollar amount, based on the gross amount of your investment (including the amount of any sales charge paid), including investments through any linked accounts in any class of any MFS fund within a 13-month period (36 months for shareholders with an LOI entered into prior to February 1, 2023, with a $1 million commitment). Distributions reinvested in additional shares of the fund or distributions from other MFS funds automatically invested in shares of the fund will not apply toward the satisfaction of the LOI.

Right Of Accumulation (ROA). Under the ROA, you may pay a reduced or no initial sales charge on purchases of Class A shares by aggregating the total dollar amount of your investment with your existing investments or any linked accounts invested in MFS funds, based on the current maximum public offering price of the funds. For example, you will pay a sales charge on your current purchase at the rate applicable to the total value of all eligible accounts.

A-9

MFS U.S. Government Cash Reserve Fund

Eligible accounts that you may link under an LOI and ROA are:

	●	Individual accounts;
	●	Joint accounts;
	●	Trust accounts of which you, your spouse (or legal equivalent under applicable state law), or child under the age of 21 is the grantor;
	●	Certain single-participant retirement plan accounts;
	●	Certain Individual Retirement Accounts;
	●	Uniform Gifts/Transfers to Minor Acts accounts; and
	●	Accounts held in the name of your financial intermediary on your behalf.

It is your responsibility to inform Ameriprise Financial for each current purchase of any accounts not held by Ameriprise Financial that hold shares of the MFS funds that you believe are eligible to be linked under an LOI or an ROA.

A-10

MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category IV

Eligible Accounts:

Accounts Investing in Class A Shares through a Morgan Stanley Wealth Management Transactional Brokerage Account Maintained at an Omnibus Level with the Fund

Shareholders purchasing fund shares through a Morgan Stanley Wealth Management transactional brokerage account will be eligible only for the following front-end sales charge waivers with respect to Class A shares, which may differ from and may be more limited than those disclosed elsewhere in the fund’s prospectus or SAI. Shareholders remain eligible for other reductions in Class A front-end sales charges available pursuant to exchange features or volume breakpoints (including Rights of Accumulation (ROA) and Letter of Intent (LOI) programs) as described elsewhere in the fund’s prospectus or SAI.

		Class A Front-end Sales Charge Waived
Waiver Category		Class A ISC
A. Dividend and Distribution Reinvestment
Shares purchased through reinvestment of dividends and capital gains distributions when purchasing shares of the same fund.		√
B. Employees of Morgan Stanley
Morgan Stanley employee and employee-related accounts according to Morgan Stanley’s account linking rules.		√
C. Reinstatement Privilege
Shares purchased from the proceeds of redemptions within the same fund family, provided (i) the repurchase occurs within 90 days following the redemption, (ii) the redemption and purchase occur in the same account, and (iii) redeemed shares were subject to a front-end or deferred sales charge.		√
D. Retirement Plans
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.		√
E. Morgan Stanley Self-Directed Programs
Shares purchased through a Morgan Stanley self-directed brokerage account.		√
F. Morgan Stanley Wealth Management Share Class Conversion Program
Class C shares that are no longer subject to a contingent deferred sales charge and are converted to Class A shares of the same fund pursuant to Morgan Stanley Wealth Management’s share class conversion program.		√

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category V

Eligible Accounts:

Accounts Investing in Shares through a Raymond James Platform or Account Maintained at an Omnibus Level by Raymond James with the Fund

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 load waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in the fund’s prospectus or SAI. In all instances, it is the purchaser’s responsibility to notify the purchaser’s financial intermediary at the time of purchase of any relationship or other facts qualifying the purchaser for sales charge waivers or discounts. As described elsewhere in the fund’s prospectus or SAI, there is no initial sales charge imposed on purchases of Class A shares pursuant to an Automatic Exchange Plan or purchased by exchange from another MFS fund.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
A. Investment Advisory Programs
Shares purchased in a Raymond James investment advisory program.	√
B. Dividend and Distribution Reinvestment
Shares purchased within the same fund family through a systematic reinvestment of capital gains and dividend distributions.	√
C. Employees/Registered Representatives of Raymond James
Shares acquired by employees and registered representatives of Raymond James or its affiliates and their family members as designated by Raymond James.	√
D. Large Purchases
Breakpoints as described in the fund’s prospectus.	√
E. Reinstatement Privilege
Shares purchased from the proceeds of redemptions within the same fund family, provided (i) the repurchase occurs within 90 days following the redemption, (ii) the redemption and purchase occur in the same account, and (iii) redeemed shares were subject to a front-end or deferred sales charge (also known as “Rights of Reinstatement”).	√	√	√	√
F. Raymond James Share Class Conversion Program
A shareholder in the fund’s Class C shares will have such Class C shares converted at net asset value to Class 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 Raymond James.	√
G. Death or Disability of Owner
Shares redeemed on account of the death or disability of the account shareholder.		√	√	√
H. Systematic Withdrawals
Systematic withdrawals with respect to up to 10% per year of the account value determined at the time of your first withdrawal under the plan(s) (or January 4, 2016, with respect to Class A shares, whichever is later).		√	√	√
I. Benefit Responsive Waivers for Retirement Accounts
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.		√	√	√

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MFS U.S. Government Cash Reserve Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
J. Payment of Raymond James Fees
Shares sold to pay Raymond James fees but only if the transaction is initiated by Raymond James.		√	√	√
K. Rights of Accumulation
Rights of accumulation which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of fund family assets held by accounts within the purchaser’s household at Raymond James. Eligible fund family 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 adviser about such assets.	√
L. Letters of Intent
Letters of intent which allow for breakpoint discounts based on anticipated purchases within a fund family over a 13-month time period. Eligible fund family 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 adviser about such assets.	√

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category VI

Eligible Accounts:

Accounts Maintained at an Omnibus Level by or on behalf of Janney Montgomery Scott LLC with the Fund

Shareholders purchasing fund shares through an account maintained at an omnibus level with the fund by Janney Montgomery Scott LLC (Janney), or by a clearing broker or custodian on behalf of Janney, will be eligible only for the following load waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in the fund’s prospectus or SAI. Customers of Janney whose accounts are established directly with the fund are not eligible for these waivers and discounts.

Shareholders remain eligible for volume breakpoints as described in the fund’s prospectus or SAI.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
A. Dividend and Distribution Reinvestment
Shares purchased of the same fund within the MFS fund family through reinvestment of capital gains and dividend distributions.	√
B. Employees/Registered Representatives of Janney
Shares purchased by employees and registered representatives of Janney or its affiliates and their family members as designated by Janney.	√
C. Reinstatement Privilege
Shares purchased from the proceeds of redemptions within the MFS fund family, provided (i) the repurchase occurs within 90 days following the redemption, (ii) the redemption and purchase occur in the same account, and (iii) redeemed shares were subject to a front-end or deferred sales charge.	√	√	√
D. Transactions Between Share Classes and Funds
Class C shares that are no longer subject to a contingent deferred sales charge and are converted to Class A shares of the same fund pursuant to Janney’s policies and procedures.	√
Shares exchanged into the same share class of another MFS fund.		√	√
E. Death or Disability of Owner
Shares redeemed upon the death or disability of the account shareholder.		√	√
F. Systematic Withdrawals
Systematic withdrawals with respect to up to 10% per year of the account value determined at the time of the shareholder’s first withdrawal under the plan(s).		√	√
G. Benefit Responsive Waivers for Retirement Accounts
Return of excess contributions from an IRA Account.		√	√
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		√	√
H. Retirement Plans
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.	√
I. Payment of Janney Fees
Shares sold to pay Janney fees but only if the transaction is initiated by Janney.		√	√

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MFS U.S. Government Cash Reserve Fund

Description of Certain Investment Programs Eligible for Sales Charge Waivers or Reductions

Right Of Accumulation (ROA). ROA, which entitles shareholders to breakpoint discounts, will be automatically calculated based on the aggregated holdings of MFS fund family assets held by accounts within the shareholder’s household at Janney. Eligible MFS fund family assets not held at Janney may be included in the ROA calculation only if the shareholder notifies his or her financial adviser about such assets.

Letter of Intent (LOI). LOI, which allow for breakpoint discounts based on anticipated purchases within the MFS fund family over a 13-month time period. Eligible MFS fund family assets not held at Janney may be included in the calculation of letters of intent only if the shareholder notifies his or her financial adviser about such assets.

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category VII

Eligible Accounts:

Accounts Investing in Shares of the Fund through an Edward Jones Platform or Account Maintained at an Omnibus Level by Edward Jones with the Fund

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 can differ from discounts and waivers described elsewhere in the fund’s prospectus or 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 MFS funds, or other facts qualifying the purchaser for breakpoints 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 breakpoints and waivers.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
A. Fee-Based Programs
Shares purchased in an Edward Jones fee-based program.	√
Shares exchanged in an Edward Jones fee-based program.		√	√	√
B. Dividend and Distribution Reinvestment
Shares purchased within the same fund family through reinvestment of capital gains and dividend distributions.	√
C. Associates of Edward Jones
Shares acquired by associates of Edward Jones and its affiliates and other shareholders 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.	√
D. Reinstatement Privilege
Shares purchased from the proceeds of redeemed shares of the same fund family so long as the following conditions are met (i) the proceeds are from the sale of shares within 60 days of the purchase; and (ii) the sale and purchase are made in the same share class and the same account or the purchase is made in an individual retirement account with proceeds from liquidations in a non-retirement account.	√
Effective January 1, 2024, “Waiver Category D. Reinstatement Privilege” above is restated in its entirety as follows:
Shares purchased from the proceeds of redeemed shares of the same fund family so long as the following conditions are met (i) the proceeds are from the sale of shares within 60 days of the purchase; and (ii) the sale and purchase are made in the same share class and one of the following applies: (a) the sale and purchase occur in the same account or (b) the sale proceeds are used to process an individual retirement account contribution, excess contributions, conversion, recharacterization of contributions, or distribution, and the purchase is done in an account within the same pricing group (as determined by Edward Jones under its policies and procedures).	√
Shares acquired through NAV reinstatement.		√	√	√
E. Transactions between Share Classes and Funds
Shares converted from another share class into Class A shares of the same fund at the discretion of Edward Jones. Edward Jones will be responsible for any remaining CDSC due to the fund company, if applicable. Any future purchases are subject to the applicable Class A sales charge as disclosed in the fund’s prospectus.	√

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MFS U.S. Government Cash Reserve Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class B CDSC	Class C CDSC
Shares converted from Class C into Class A shares of the same fund, generally, in the 84^th month following the anniversary of the purchase date or earlier at the discretion of Edward Jones.	√
Shares exchanged from another MFS Fund in an Edward Jones fee-based program.	√	√	√	√
F. Death or Disability of Owner
Shares redeemed on account of the death or disability of the account shareholder or 529 plan account beneficiary.		√	√	√
G. Systematic Withdrawals
Systematic withdrawals with respect to up to 10% per year of the account value determined at the time of the shareholder’s first withdrawal under the plan(s).		√	√	√
H. Benefit Responsive Waivers for Retirement Accounts
Return of excess contributions from an IRA Account.		√	√	√
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.		√	√	√
I. Payment of Edward Jones Fees
Shares sold to pay Edward Jones fees or costs but only if the transaction is initiated by Edward Jones.		√	√	√
J. Large Purchases
Breakpoint amounts as described in the fund’s prospectus, subject to the Rights of Accumulation rules described below.	√
K. Minimum Balances
Shares redeemed at the discretion of Edward Jones for Minimum Balances, as described below.		√	√	√

Description of Certain Policies for Sales Charge Waivers or Reductions

Letter Of Intent (LOI). A shareholder may pay a reduced or no initial sales charge on purchases of Class A shares if the shareholder intends to invest a specific dollar amount in any class of any MFS fund within a 13-month period. The LOI is determined by calculating the higher of the cost paid by the shareholder or the market value of any existing qualifying holdings (as calculated at the beginning of the 13-month period) in combination with the value that the shareholder intends to purchase over a 13-month period to calculate the front-end sales charge and any breakpoint discounts. Each purchase the shareholder makes during the 13-month period will receive the sales charge and breakpoint discount that applies to the total amount.

If the shareholder does not purchase the intended amount within the 13-month period, the shareholder’s account will be adjusted by redemption of the amount of shares needed to pay the higher initial sales charge level for the amount actually purchased. Purchases made before the LOI is received by Edward Jones are not adjusted under the LOI and will not reduce any sales charge previously paid. The inclusion of investments in the MFS funds held in accounts not maintained by Edward Jones is dependent on the shareholder notifying Edward Jones of such investments at the time of calculation. 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.

Right Of Accumulation (ROA). Under the ROA, a shareholder may pay a reduced or no initial sales charge on purchases of Class A shares by aggregating the amount of the shareholder’s investment with the shareholder’s existing investments in the MFS funds, based on the higher of the cost paid by the shareholder minus redemptions or the current market value of the applicable MFS funds. For purposes of calculating the ROA, the shareholder’s account may be grouped by Edward Jones with other accounts for the purpose of providing certain pricing considerations (“pricing groups”) (as determined by Edward Jones under its policies and procedures). For purposes of calculating the ROA, holdings of shares of certain money market funds or shares held in group retirement plans are not taken into account. If grouping assets as a shareholder, the ROA includes all investments of a shareholder in the MFS funds held on the Edward Jones platform and/or held on other platforms. The inclusion of investments in the MFS funds held in accounts not maintained by Edward Jones is dependent on the shareholder notifying Edward Jones of such investments 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

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MFS U.S. Government Cash Reserve Fund

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.

Other Important Information Regarding Transactions Through Edward Jones

Minimum Purchase Amounts. Purchases by shareholders will be subject to a $250 initial purchase minimum and no subsequent purchase minimum.

Minimum Balances. Edward Jones has the right to redeem at its discretion fund holdings with a balance of $250 or less. The following accounts are not subject to this minimum balance policy: (1) a fee-based account held on an Edward Jones platform; (2) a 529 account held on an Edward Jones platform; or (3) an account with an active systematic investment plan or LOI (as defined above).

Changing Share Classes. At any time it deems necessary, Edward Jones has the authority to convert at NAV a shareholder’s holdings in a fund to Class A shares of the same fund.

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category VIII

Eligible Accounts:

Accounts Investing in Shares of the Fund through a D.A. Davidson & Co. Platform or Account Maintained at an Omnibus Level by or on behalf of D.A. Davidson & Co. with the Fund

Shareholders purchasing fund shares, including existing fund shareholders, through a D.A. Davidson &. Co. (D.A. Davidson) platform or account, or through an introducing broker-dealer or independent registered investment adviser for which D.A. Davidson provides trade execution, clearance, and/or custody services, where such account is maintained on an omnibus level with the fund by D.A. Davidson, or by a clearing broker or custodian on behalf of D.A. Davidson, 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 the fund’s prospectus or SAI. Customers of D.A. Davidson whose accounts are established directly with the fund are not eligible for these waivers and discounts.

Shareholders remain eligible for volume breakpoints as described in the fund’s prospectus or SAI.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
A. Dividend and Distribution Reinvestment
Shares purchased within the MFS fund family through systematic reinvestment of capital gains and dividend distributions.	√
B. Employees/Registered Representatives of D.A. Davidson
Shares acquired by employees and registered representatives of D.A. Davidson or its affiliates and their family members as designated by D.A. Davidson.	√
C. Reinstatement Privilege
Shares purchased from the proceeds of redeemed shares of the MFS fund family so long as the following conditions are met (i) the repurchase occurs within 90 days following the redemption; (ii) the redemption and purchase occur in the same account; and (iii) redeemed shares were subject to a front-end or deferred sales charge (known as Rights of Reinstatement).	√	√	√
D. Transactions between Share Classes and Funds
A shareholder in the fund’s Class C shares will have such Class C shares converted at net asset value to Class 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 D.A. Davidson.	√
Shares exchanged into the same share class of another MFS Fund.	√	√	√
E. Death or Disability of Owner
Shares redeemed on account of the death or disability of the account shareholder.		√	√
F. Systematic Withdrawals
Shares sold as part of a systematic withdrawal plan as described in the fund’s prospectus.		√	√
G. Benefit Responsive Waivers for Retirement Accounts
Return of excess contributions from an IRA Account.		√	√
Shares sold as part of a required minimum distribution for IRA or other qualifying retirement accounts if the redemption is taken in or after the year the shareholder reaches the qualified age based on IRS regulations.		√	√

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category IX

Eligible Accounts:

Accounts Investing in Shares through a Baird Platform or Account Maintained at an Omnibus Level by or on behalf of Baird with the Fund

Shareholders purchasing fund shares through a Baird platform or account maintained at an omnibus level with the fund by Baird, or by a clearing broker or custodian on behalf of Baird, 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 the fund’s prospectus or the SAI. Customers of Baird whose accounts are established directly with the fund are not eligible for these waivers and discounts.

Shareholders remain eligible for volume breakpoints as described in the fund’s prospectus or SAI.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
A. Dividend and Distribution Reinvestment
Shares purchased through reinvestment of dividends and capital gains distributions when purchasing shares of the same fund.	√
B. Employees/Registered Representatives of Baird
Shares acquired by employees and registered representatives of Baird or its affiliates and their family members as designated by Baird.	√
C. Reinstatement Privilege
Shares purchased from the proceeds of redemptions from another MFS fund, provided (i) the repurchase occurs within 90 days following the redemption, (ii) the redemption and purchase occur in the same account, and (iii) redeemed shares were subject to a front-end or deferred sales charge (also known as “Rights of Reinstatement”).	√	√	√
D. Transactions between Share Classes and Funds
A shareholder in the fund’s Class C shares will have such Class C shares converted at net asset value to Class 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 Baird.	√
Shares exchanged into the same share class of another MFS Fund.	√	√	√
E. Retirement Plans
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.	√
F. Death or Disability of Owner
Shares redeemed on account of the death or disability of the account shareholder.		√	√
G. Systematic Withdrawals
Shares sold as part of a systematic withdrawal plan as described in the fund’s prospectus.		√	√
H. Benefit Responsive Waivers for Retirement Accounts
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.		√	√

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MFS U.S. Government Cash Reserve Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
I. Payment of Baird Fees
Shares sold to pay Baird fees but only if the transaction is initiated by Baird.		√	√
J. Rights of Accumulation
Rights of Accumulations (ROAs) which entitles shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of MFS fund family assets held by accounts within the purchaser’s household at Baird. Eligible MFS fund family assets not held at Baird may be included in the rights of accumulations calculation only if the shareholder notifies his or her financial adviser about such assets.	√
K. Letters of Intent
Letters of Intent (LOI) allow for breakpoint discounts based on anticipated purchases of MFS fund family assets through Baird, over a 13-month period of time.	√

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category X

Eligible Accounts:

Accounts Investing in Shares through a J.P. Morgan Securities LLC Platform or Account Maintained at an Omnibus Level by J.P. Morgan Securities LLC with the Fund

If you purchase or hold fund shares through an applicable J.P. Morgan Securities LLC brokerage account, you will be eligible for the following sales charge waivers (front-end sales charge waivers and CDSC, or back-end sales charge, waivers), share class conversion policy and discounts, which may differ from those disclosed elsewhere in the fund’s prospectus or SAI.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
A. Transactions between Share Classes
Shares exchanged from Class C (i.e., level-load) shares that are no longer subject to a CDSC and are exchanged into Class A shares of the same fund pursuant to J.P. Morgan Securities LLC’s share class exchange policy.	√
A shareholder in the fund’s Class C shares will have their shares converted by J.P. Morgan Securities LLC to Class A shares (or the appropriate share class) of the same fund if the shares are no longer subject to a CDSC and the conversion is consistent with J.P. Morgan Securities LLC’s policies and procedures.	√
B. Retirement Plans
Qualified employer-sponsored defined contribution and defined benefit retirement plans, nonqualified deferred compensation plans, other employee benefit plans and trusts used to fund those plans. For purposes of this provision, such plans do not include SEP IRAs, SIMPLE IRAs, SAR-SEPs or 501(c)(3) accounts.	√
C. J.P. Morgan Securities LLC Self-Directed Investing accounts
Shares of funds purchased through J.P. Morgan Securities LLC Self-Directed Investing accounts.	√
D. Reinstatement Privilege
Shares purchased through rights of reinstatement.	√
Shares acquired through a right of reinstatement.		√	√
E. Dividend and Distribution Reinvestment
Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family).	√
F. Employees/Registered Representatives of J.P. Morgan Securities LLC
Shares purchased by employees and registered representatives of J.P. Morgan Securities LLC or its affiliates and their spouse or financial dependent as defined by J.P. Morgan Securities LLC.	√
G. Death or Disability of Owner
Shares sold upon the death or disability of the shareholder.		√	√
H. Systematic Withdrawals
Shares sold as part of a systematic withdrawal plan as described in the fund’s prospectus.		√	√
I. Benefit Responsive Waivers for Retirement Accounts
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.		√	√

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MFS U.S. Government Cash Reserve Fund

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
J. Large Purchases
Breakpoints as described in the prospectus.	√
K. Rights of Accumulation
Rights of Accumulation (“ROA”) which entitle shareholders to breakpoint discounts as described in the fund’s prospectus will be automatically calculated based on the aggregated holding of fund family assets held by accounts within the purchaser’s household at J.P. Morgan Securities LLC. Eligible fund family assets not held at J.P. Morgan Securities LLC (including 529 program holdings, where applicable) may be included in the ROA calculation only if the shareholder notifies their financial advisor about such assets.	√
L. Letters of Intent
Letters of Intent (“LOI”) which allow for breakpoint discounts based on anticipated purchases within a fund family, through J.P. Morgan Securities LLC, over a 13-month period of time (if applicable).	√

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MFS U.S. Government Cash Reserve Fund

Financial Intermediary Category XI

Eligible Accounts:

Accounts Investing in Shares through a Stifel Platform or Account Maintained at an Omnibus Level by Stifel with the Fund

Shareholders purchasing or holding fund shares, including existing fund shareholders, through a Stifel or affiliated platform that provides trade execution, clearance, and/or custody services, will be eligible for the following sales charge load waivers (including front-end sales charge waivers and CDSC, or back-end sales charge, waivers) and discounts, which may differ from those disclosed elsewhere in the fund’s prospectus or SAI.

As described elsewhere in this prospectus, Stifel may receive compensation out of the front-end sales charge if you purchase Class A shares through Stifel.

All other sales charge waivers and reductions described elsewhere in the fund’s prospectus or SAI still apply.

	Sales Charge Waived
Waiver Category	Class A ISC	Class A CDSC	Class C CDSC
A. Front-end sales charge waivers on Class A shares available at Stifel
A shareholder in the fund’s Class C shares will have such Class C shares converted at net asset value to Class A shares of the fund in the 7^thyear following the anniversary of the purchase date or earlier at the discretion of Stifel, but in no event earlier than the expiration of the applicable Class C CDSC.	√
Shares purchased by employees and registered representatives of Stifel or its affiliates and their family members as designated by Stifel.	√
Shares purchased in an Stifel fee-based advisory program (often referred to as a “wrap” program).	√
Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same or other fund within the MFS fund family.	√
Shares purchased from the proceeds of redemptions within the same fund family provided the proceeds are from the sale of shares from an account with the same owner/beneficiary within 90 days of the purchase. For the absence of doubt, shares redeemed through a Systematic Withdrawal Plan are not eligible for rights of reinstatement.	√
Shares from rollovers into Stifel from retirement plans to IRAs.	√
Shares exchanged into Class A shares from another share class so long as the exchange is into the same fund and was initiated at the direction of Stifel. Stifel is responsible for any remaining CDSC due to MFS, if applicable. Any future purchases are subject to the applicable Class A sales charge as disclosed in the applicable fund’s prospectus.	√
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.	√
B. CDSC Waivers on Class A and Class C Shares
Death or disability of the shareholder or, in the case of 529 plans, the account beneficiary.		√	√
Shares sold as part of a systematic withdrawal plan not to exceed 12% annually.		√	√
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.		√	√
Shares acquired through a right of reinstatement.		√	√
Shares sold to pay Stifel fees or costs in such cases where the transaction is initiated by Stifel.		√	√

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MFS U.S. Government Cash Reserve Fund

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MFS U.S. Government Cash Reserve Fund

MFS U.S. Government Cash Reserve Fund

Shareholder Communications with the Board of Trustees. Shareholders may mail written communications to the Board of Trustees to the attention of the Board of Trustees, [fund name], Massachusetts Financial Services Company, 111 Huntington Avenue, Boston, MA 02199, Attention: Fund Secretary. Shareholder communications must (i) be in writing and be signed by the shareholder, (ii) identify the MFS fund to which they relate, and (iii) identify the class and number of shares held by the shareholder.

If you want more information about MFS U.S. Government Cash Reserve Fund, the following documents are available free upon request:

Annual/Semiannual Reports. These reports contain information about the fund’s actual investments.

Statement of Additional Information (SAI). The SAI, dated December 29, 2023, as may be amended or supplemented from time to time, provides more detailed information about the fund and is incorporated into this prospectus by reference.

You can get free copies of the annual/semiannual reports, the SAI and other information about the fund, including current net asset values per share, and make inquiries about the fund, by contacting:

Internet: mfs.com

MFS Service Center, Inc.

P.O. Box 219341

Kansas City, MO 64121-9341

Telephone: 1-800-225-2606

Reports and other information about the fund are available on the EDGAR Database on the Commission’s Internet website at http://www.sec.gov, and copies of this information may be obtained, upon payment of a duplicating fee, by electronic request at the following e-mail address: [email protected].

The fund’s Investment Company Act file number is 811-4777.

HOW TO CONTACT US

Website

mfs.com

MFS TALK

1-800-637-8255

24 hours a day

Account service and literature

Shareholders

1-800-225-2606

Investment professionals

1-800-343-2829

Retirement plan services

1-800-637-1255

Mailing address

MFS Service Center, Inc.

P.O. Box 219341

Kansas City, MO 64121-9341

Overnight mail

MFS Service Center, Inc.

Suite 219341

430 W 7^th Street

Kansas City, MO 64105-1407

Table of contents

SUMMARY OF KEY INFORMATION			2
INVESTMENT OBJECTIVE, STRATEGIES, AND RISKS			5
MANAGEMENT OF THE FUND			6
DESCRIPTION OF SHARE CLASSES			7
HOW TO PURCHASE, REDEEM, AND EXCHANGE SHARES			10
OTHER INFORMATION			14
FINANCIAL HIGHLIGHTS			16
APPENDIX A – WAIVERS AND REDUCTIONS OF SALES CHARGES			A-1

Sales Charge Waived

Waiver Category

Class A
ISC

Class A
CDSC

Class C
CDSC

H. Rights of Accumulation

Rights of accumulation which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of MFS fund family assets held by accounts within the purchaser’s household at D.A. Davidson. Eligible MFS fund family 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 adviser about such assets.

I. Letters of Intent

Letters of intent which allow for breakpoint discounts based on anticipated purchases within the MFS fund family over a 13-month time period. Eligible MFS fund family 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 adviser about such assets.