The report is prepared for the general information of shareholders. It is authorized for distribution to prospective investors only when preceded or accompanied by a current prospectus.

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LETTER FROM THE EXECUTIVE CHAIR

Dear Shareholders:

Markets experienced dramatic swings this year as the coronavirus pandemic brought the global economy to a standstill for several months early in the year, though

optimism over the development of vaccines and therapeutics later brightened the economic and market outlook. However, a great deal of uncertainty remains as case counts in the United States and Europe remain very high and it is still unclear when a vaccine will become widely available. In the United States, political uncertainty eased after former Vice President Joe Biden was projected the winner of the presidential election, though whether his party also gains control of Congress will not be known until two Senate runoff elections in Georgia in early January.

Global central banks have taken aggressive steps to cushion the economic and market fallout related to the virus, and

governments are deploying unprecedented levels of fiscal support, though in the U.S. some of those measures were allowed to lapse at the end of July as negotiators found themselves at an impasse over the scope of additional funding. The measures already put in place have helped build a supportive environment and are encouraging economic recovery; however, if markets disconnect from fundamentals, they can also sow the seeds of instability. In the aftermath of the crisis, societal changes may be likely as households, businesses, and governments adjust to a new reality, and any such alterations could affect the investment landscape. For investors, events such as the COVID-19 outbreak demonstrate the importance of having a deep understanding of company fundamentals, and we have built our global research platform to do just that.

Here at MFS®, we aim to help our clients navigate the growing complexity of the markets and world economies. Our long-term investment philosophy and commitment to the responsible allocation of capital allow us to tune out the noise and uncover what we believe are the best, most durable investment opportunities in the market. Through our unique global investment platform, we combine collective expertise, thoughtful risk management, and long-term discipline to create sustainable value for investors.

Respectfully,

Robert J. Manning

Executive Chair

MFS Investment Management

December 16, 2020

The opinions expressed in this letter are subject to change and may not be relied upon for investment advice. No forecasts can be guaranteed.

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PORTFOLIO COMPOSITION

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Portfolio Composition – continued

Cash & Cash Equivalents includes any cash, investments in money market funds, short-term securities, and other assets less liabilities. Please see the Statement of Assets and Liabilities for additional information related to the fund’s cash position and other assets and liabilities.

Other includes equivalent exposure from currency derivatives and/or any offsets to derivative positions and may be negative.

Percentages are based on net assets as of October 31, 2020.

The portfolio is actively managed and current holdings may be different.

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MANAGEMENT REVIEW

Summary of Results

For the twelve months ended October 31, 2020, Class A shares of the MFS Global Equity Fund (fund) provided a total return of 0.83%, at net asset value. This compares with a return of 4.36% for the fund’s benchmark, the MSCI World Index (net div).

Market Environment

Markets experienced an extraordinarily sharp selloff and, in many cases, an unusually rapid recovery late in the period. Central banks and fiscal authorities undertook astonishing levels of stimulus to offset the economic effects of government-imposed social-distancing measures implemented to slow the spread of the COVID-19 virus. At this point, the global economy looks to have experienced the deepest, steepest and possibly shortest recession in the postwar period. However, the recovery remains subject to more than the usual number of uncertainties due to questions about the evolution of the virus, what its continued impact will be and when vaccines or medicines will become available to prevent or treat it.

Around the world, central banks responded quickly and massively to the crisis with programs to improve liquidity and support markets. These programs proved largely successful in helping to restore market function, ease volatility and stimulate a continued market rebound. Late in the period, the US Federal Reserve adopted a new, flexible average-inflation-targeting framework, which is expected to result in policy rates remaining at low levels for a longer period. In developed countries, monetary easing measures were complemented by large fiscal stimulus initiatives, although late in the period there was uncertainty surrounding the timing and scope of additional US recovery funding. Due to relatively manageable external liabilities and balances of payments in many countries, along with persistently low inflation, even emerging market countries were able to implement countercyclical policies – a departure from the usual market-dictated response to risk-off crises.

Compounding market uncertainty earlier in the pandemic was a crash in the price of crude oil due to a sharp drop in global demand and a disagreement between Saudi Arabia and Russia over production cuts, which resulted in a price war. The subsequent decline in prices undercut oil exporters, many of which are in emerging markets, as well as a large segment of the high-yield credit market. The OPEC+ group later agreed on output cuts, with shale oil producers in the United States also decreasing production, which, along with the gradual reopening of some major economies and the resultant boost in demand, helped stabilize the price of crude oil.

As has often been the case in a crisis, market vulnerabilities have been revealed. For example, companies that have added significant leverage to their balance sheets in recent years by borrowing to fund dividend payments and stock buybacks have, in many cases, halted share repurchases and cut dividends, while some firms have been forced to recapitalize.

Detractors from Performance

A combination of security selection and underweight positions in both the information technology and consumer discretionary sectors detracted from performance relative to the MSCI World Index. Within the information technology sector, not owning shares of

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Management Review – continued

strong-performing computer and personal electronics maker Apple and software giant Microsoft held back relative performance. The stock price of Apple increased during the reporting period. Despite headwinds related to COVID-19, Apple delivered strong results as product demand recovered more rapidly than expected. The shift toward work-from-home and remote learning helped support strong iPhone and iPad sales. Within the consumer discretionary sector, not owning shares of internet retailer Amazon.com and electric vehicle manufacturer Tesla weighed on relative performance. The share price of Amazon.com advanced as strong e-commerce volumes drove robust revenue and earnings that beat market expectations. Solid growth in the company’s Amazon Web Services cloud division also supported results. The fund’s overweight position in food catering company Compass Group (United Kingdom) also weakened relative returns.

Elsewhere, the fund’s overweight positions in food processing company Danone (France), life sciences company Bayer (Germany), diversified industrial manufacturer Rolls-Royce Holdings (United Kingdom) and premium drinks distributer Diageo (United Kingdom) hindered relative performance. Not owning shares of technology company Alphabet also held back relative returns. Shares of Alphabet rose as the company delivered revenue results that were ahead of estimates, driven by growth in Google Play & YouTube subscriptions and strength in search revenues.

Contributors to Performance

The fund’s underweight position in the energy sector contributed to relative performance during the reporting period. Within this sector, not holding shares of weak-performing integrated oil and gas company Exxon Mobil and global energy and petrochemicals company Royal Dutch Shell (United Kingdom) benefited relative results. The stock price of Exxon Mobil came under pressure after the company reported weaker-than-expected earnings, driven by lower prices, volume and production.

An underweight position in the financials sector further supported relative results, led by the fund’s avoidance of weak-performing diversified financial services firm Wells Fargo. The stock price of Wells Fargo declined, along with many other financial services stocks, as bond yields collapsed, notably on 10-year US Treasury bonds, and concerns about increased potential loan losses arose as global economic activity ground to a halt in efforts to stem the spread of the COVID-19 virus.

Stocks in other sectors that helped relative returns included the fund’s overweight positions in life sciences supply company Thermo Fisher Scientific, electrical distribution equipment manufacturer Schneider Electric (France), railroad company Kansas City Southern, ground delivery service company United Parcel Service, IT servicing firm Accenture and digital payment technology developer PayPal Holdings.

The timing of the fund’s cash and/or cash equivalents position during the period was also a contributor to relative performance. Under normal market conditions, the fund strives to be fully invested and generally holds cash to buy new holdings and to provide liquidity.

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Respectfully,

Portfolio Manager(s)

Ryan McAllister and Roger Morley

The views expressed in this report are those of the portfolio manager(s) only through the end of the period of the report as stated on the cover and do not necessarily reflect the views of MFS or any other person in the MFS organization. These views are subject to change at any time based on market or other conditions, and MFS disclaims any responsibility to update such views. These views may not be relied upon as investment advice or an indication of trading intent on behalf of any MFS portfolio. References to specific securities are not recommendations of such securities, and may not be representative of any MFS portfolio’s current or future investments.

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PERFORMANCE SUMMARY THROUGH 10/31/20

The following chart illustrates a representative class of the fund’s historical performance in comparison to its benchmark(s). Performance results include the deduction of the maximum applicable sales charge and reflect the percentage change in net asset value, including reinvestment of dividends and capital gains distributions. The performance of other share classes will be greater than or less than that of the class depicted below. Benchmarks are unmanaged and may not be invested in directly. Benchmark returns do not reflect sales charges, commissions or expenses. (See Notes to Performance Summary.)

Performance data shown represents past performance and is no guarantee of future results. Investment return and principal value fluctuate so your shares, when sold, may be worth more or less than the original cost; current performance may be lower or higher than quoted. The performance shown does not reflect the deduction of taxes, if any, that a shareholder would pay on fund distributions or the redemption of fund shares.

Growth of a Hypothetical $10,000 Investment

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Total Returns through 10/31/20

Average annual without sales charge

CDSC – Contingent Deferred Sales Charge.

Class I, R1, R2, R3, R4, and R6 shares do not have a sales charge.

Benchmark Definition(s)

MSCI World Index ^(e) (net div) – a market capitalization-weighted index that is designed to measure equity market performance in the global developed markets.

It is not possible to invest directly in an index.

Notes to Performance Summary

Average annual total return represents the average annual change in value for each share class for the periods presented. Life returns are presented where the share class has less than 10 years of performance history and represent the average annual total

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Performance Summary – continued

return from the class inception date to the stated period end date. As the fund’s share classes may have different inception dates, the life returns may represent different time periods and may not be comparable. As a result, no comparative benchmark performance information is provided for life periods.

Performance results reflect any applicable expense subsidies and waivers in effect during the periods shown. Without such subsidies and waivers the fund’s performance results would be less favorable. Please see the prospectus and financial statements for complete details.

Performance results do not include adjustments made for financial reporting purposes in accordance with U.S. generally accepted accounting principles and may differ from amounts reported in the financial highlights.

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

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EXPENSE TABLE

Fund expenses borne by the shareholders during the period, May 1, 2020 through October 31, 2020

As a shareholder of the fund, you incur two types of costs: (1) transaction costs, including sales charges (loads) on certain purchase or redemption payments, and (2) ongoing costs, including management fees; distribution and service (12b-1) fees; and other fund expenses. This example is intended to help you understand your ongoing costs (in dollars) of investing in the fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period May 1, 2020 through October 31, 2020.

Actual Expenses

The first line for each share class in the following table provides information about actual account values and actual expenses. You may use the information in this line, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the first line under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes

The second line for each share class in the following table provides information about hypothetical account values and hypothetical expenses based on the fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the fund’s actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds.

Please note that the expenses shown in the table are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as sales charges (loads). Therefore, the second line for each share class in the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. In addition, if these transactional costs were included, your costs would have been higher.

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Expense Table – continued

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Portfolio of Investments – continued

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Portfolio of Investments – continued

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Abbreviations indicate amounts shown in currencies other than the U.S. dollar. All amounts are stated in U.S. dollars unless otherwise indicated. A list of abbreviations is shown below:

See Notes to Financial Statements

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