Summary Prospectus June 28, 2022

MFS^®New Discovery Value Fund

Beforeyou invest, you may want to review the fund’s prospectus, which contains more information about the fund and its risks.You can find the fund’s prospectus and other information about the fund, including the fund’s reports to shareholders andstatement of additional information, online at funds.mfs.com. You can also get this information at no cost by calling 1-800-225-2606or by sending an e-mail request to orderliterature@mfs.com. The fund’s prospectus and statement of additional information, bothdated June 28, 2022, as may be amended or supplemented from time to time, are incorporated by reference into this summary prospectus.

Summaryof Key Information

InvestmentObjective

The fund’s investment objective is to seek capital appreciation.

Feesand Expenses

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

You may qualify for sales charge reductions if, with respect to Class Ashares, you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS funds. More informationabout these and other waivers and reductions is available from your financial intermediary and in “Sales Charges and Waivers andReductions” on page 10 and “Appendix A – Waivers and Reductions of Sales Charges” on page A-1 of thefund’s prospectus.

Shareholder Fees (fees paid directly from your investment):

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

NDV-SUM-062822

MFS New Discovery Value Fund

Example

This example is intended to help you compare the cost of investingin the fund with the cost of investing in other mutual funds.

The example assumes that: you invest $10,000 in the fund for the timeperiods indicated and you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% returneach year; and the fund’s operating expenses remain the same.

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

PortfolioTurnover

The fund pays transaction costs, such as commissions, when it buysand sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costsand may result in higher taxes when shares are held in a taxable account. These transaction costs, which are not reflected in “AnnualFund Operating Expenses” or in the “Example,” affect the fund’s performance. During the most recent fiscal year,the fund’s portfolio turnover rate was 44% of the average value of its portfolio.

PrincipalInvestment Strategies

MFS (Massachusetts Financial Services Company, the fund's investmentadviser) normally invests the fund’s assets primarily in equity securities. Equity securities include common stocks, equity interestsin real estate investment trusts (REITs), and other securities that represent an ownership interest (or right to acquire an ownershipinterest) in a company or other issuer.

MFS focuses on investing the fund's assets in the stocks of companiesit believes are undervalued compared to their perceived worth (value companies).

While MFS may invest the fund’s assets in securities of companiesof any size, MFS primarily invests in securities of companies with small capitalizations.

MFS may invest the fund’s assets in foreign securities.

MFS normally invests the fund's assets across different industriesand sectors, but MFS may invest a significant percentage of the fund's assets in issuers in a single industry or sector.

MFS uses an active bottom-up investment approach to buying and sellinginvestments for the fund. Investments are selected primarily based on fundamental analysis of individual issuers. Quantitative screeningtools that systematically evaluate issuers may also be considered.

PrincipalRisks

As with any mutual fund, the fund may not achieve its objective and/oryou could lose money on your investment in the fund. An investment in the fund is not a bank deposit and is not insured or guaranteedby the Federal Deposit Insurance Corporation or any other governmental agency.

The principal risks of investing in the fund are:

InvestmentSelection Risk: MFS' investment analysis and its selection of investments may not produce the intended results and/or canlead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperformingthe markets in which the fund invests.

EquityMarket Risk/Company Risk: Equity markets are volatile and can decline significantly in response to, or investor perceptionsof, issuer, market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. Theseconditions can affect a single issuer or type of security, issuers within a broad market sector, industry or geographic region, or theequity markets in general. Certain events can have a dramatic adverse effect on equity markets and may lead to periods of high volatilityin an equity market or a segment of an equity market. The value of an investment held by the fund may decline due to factors directlyrelated to the issuer.

ValueCompany Risk: The stocks of value companies can continue to be undervalued for long periods of time and not realize theirexpected value and can be more volatile than the market in general.

SmallCap Risk: The stocks of small cap companies can be more volatile and their shares can be less liquid than those of largercompanies.

ForeignRisk: Exposure to foreign markets through issuers or currencies can involve additional risks relating to market, economic,industry, political, regulatory, geopolitical, environmental, public health, and other conditions. These factors can make foreign investments,especially those tied economically to emerging and frontier markets, more volatile and less liquid than U.S. investments. In addition,foreign markets can react differently to these conditions than the U.S. market.

REITsRisk: The risks of investing in REITs include certain risks associated with the direct ownership of real estate and the realestate industry in general. These include risks related to general, regional and local economic conditions; difficulties in valuing anddisposing of real estate; fluctuations in interest rates and property tax rates; shifts in zoning laws, environmental regulations andother governmental action; cash flow dependency; increased operating expenses; lack of availability of mortgage funds; losses due tonatural disasters; overbuilding; losses due to casualty or condemnation; changes in property values and rental rates; the managementskill and creditworthiness of the REIT manager; and other factors. The securities of smaller real estate-related issuers can be morevolatile and less liquid than securities of larger issuers and their issuers can have more limited financial resources.

FocusRisk: Issuers in a single industry, sector, country, or region can react similarly to market, currency, political, economic,regulatory, geopolitical, environmental, public health, and other conditions, and the fund's performance will be affected by the

MFS New Discovery Value Fund

conditions in the industries, sectors, countries and regions to whichthe fund is exposed.

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

LargeShareholder 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 sellsecurities or invest additional cash, as the case may be, at disadvantageous prices. Redemptions of a large number of shares also mayincrease transaction and other costs or have adverse tax consequences for shareholders of the fund by requiring a sale of portfolio securities.Purchases of a large number of shares may adversely affect the fund's performance to the extent that it takes time to invest new cashand the fund maintains a larger cash position than it ordinarily would.

PerformanceInformation

The bar chart and performance table below are intended to providesome indication of the risks of investing in the fund by showing changes in the fund’s performance over time and how the fund’sperformance over time compares with that of a broad measure of market performance.

The fund’s past performance (before and after taxes) does notnecessarily indicate how the fund will perform in the future. Updated performance is available online at mfs.comor by calling 1-800-225-2606.

Class ABar Chart. The bar chart does not take into account any sales charges (loads) that you may be required to pay upon purchaseor redemption of the fund’s shares. If these sales charges were included, they would reduce the returns shown.

Thetotal return for the three-month period ended March 31, 2022, was (2.41)%. During the period(s) shown in the bar chart, thehighest quarterly return was 30.96% (for the calendar quarter ended December 31, 2020) and the lowest quarterly return was (34.36)%(for the calendar quarter ended March 31, 2020).

PerformanceTable.

Average Annual Total Returns

(For the Periods Ended December 31, 2021)            

After-taxreturns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of stateand local taxes. Your actual after-tax returns will depend on your own tax situation, and may differ from those shown. The after-taxreturns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans or individualretirement accounts. The after-tax returns are shown for only one of the fund’s classes of shares, and after-tax returns for thefund’s other classes of shares will vary from the returns shown.

InvestmentAdviser

MFS serves as the investment adviser for the fund.

PortfolioManager(s)

Purchaseand Sale of Fund Shares

You may purchase and redeem shares of the fund each day the New YorkStock Exchange (the NYSE) is open for trading. You may purchase or redeem shares either by having your financial intermediary processyour purchase or redemption, or through MFS Service Center, Inc. (MFSC) by overnight mail (MFSC, Suite 219341, 430 W 7^thStreet, 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 generallyare as follows:

MFS New Discovery Value Fund

Effective at the close of business on August 14, 2019 (the ClosingDate), the fund is closed to new investors subject to certain exceptions. Shareholders of the fund as of the Closing Date can continueto make additional purchases and reinvest distributions in the fund in any account open as of the Closing Date. Shareholders of the fundas of the Closing Date may also: 1) exercise their one-time Reinstatement Privilege (described in Appendix A of this prospectus) to reinvestin shares of the fund within 90 days of a redemption of fund shares; and 2) transfer some or all of the shares in their account to anotheraccount and such account will be treated as having been open as of the Closing Date.

In addition, as of the Closing Date, shares of the fund may be purchasedby the following investors:

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 restrictionswith respect to their investors. MFS' ability to monitor financial intermediaries' enforcement of these restrictions is limited by operationalsystems and the cooperation of financial intermediaries. In addition, with respect to omnibus accounts, MFS' ability to monitor is alsolimited by a lack of information with respect to the underlying shareholder accounts.

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

Taxes

If your shares are held in a taxable account, the fund’s distributionswill be taxed to you as ordinary income and/or capital gains. If your shares are held in a tax-advantaged account, you will generallybe taxed only upon withdrawals from the account.

Paymentsto Broker/Dealers and Other Financial Intermediaries

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