Filing by Investment Company (SEC Filing - 497K)

Before you 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 Statement of Additional Information and most recent reports, online at www.jhinvestments.com/prospectuses. You can also get this information at no cost by calling 800-225-5291 (Class A and Class C) or 888-972-8696 (Class I and Class R Suite) or by sending an email request to [email protected]. The fund's prospectus and Statement of Additional Information, both dated 1/1/21, as may be supplemented, and most recent financial highlights information included in the shareholder report, dated 8/31/20, are incorporated by reference into this summary prospectus.

Tickers

Investment objective

Seeks to provide a high level of current income with consideration for capital appreciation and preservation.

Fees and expenses

This table describes the fees and expenses you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts on Class A shares if you and your family invest, or agree to invest in the future, at least $50,000 in the John Hancock family of funds. Intermediaries may have different policies and procedures regarding the availability of front-end sales charge waivers or contingent deferred sales charge (CDSC) waivers (See Appendix 1 - Intermediary sales charge waivers, which includes information about specific sales charge waivers applicable to the intermediaries identified therein). More information about these and other discounts is available from your financial professional and on pages 27 to 29 of the prospectus under 'Sales charge reductions and waivers' or pages 167 to 170 of the fund's Statement of Additional Information under 'Sales Charges on Class A and Class C Shares.'

John Hancock Multi-Asset High Income Fund

Expense 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. Please see below a hypothetical example showing the expenses of a $10,000 investment for the time periods indicated and then, except as shown below, assuming you sell all of your shares at the end of those periods. The example assumes a 5% average annual return and that fund expenses will not change over the periods. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Portfolio turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or 'turns over' its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund's performance. During its most recent fiscal year, the fund's portfolio turnover rate was 42% of the average value of its portfolio.

Principal investment strategies

The fund has significant flexibility to achieve its investment objective and invests in a broad range of income-producing securities. The fund invests in debt and equity securities, as well as derivative instruments, in the U.S. and developed and emerging markets throughout the world. There is no limit on the number of countries in which the fund may invest, and the fund may focus its investments in a single country or a small group of countries. As attractive investments across asset classes and strategies arise, the manager attempts to capture these opportunities and has wide latitude to allocate the fund's assets among strategies and asset classes. The manager buys and sells securities and investments for the fund based on the manager's views of strategies, sectors, and overall portfolio construction taking into account income generation, risk/return analyses, and relative value considerations.

Under normal market circumstances the fund invests in a broad range of income-producing securities across asset classes as market conditions warrant, but the fund may invest up to 100% of its assets in fixed-income securities and may invest up to 70% of its assets in equity securities from time to time to adjust to prevailing market conditions.

The fund may invest in individual fixed-income securities to the fullest extent permissible. The fund may invest in a portfolio of fixed income securities such as corporate bonds and notes, mortgage-backed securities, asset-backed securities, convertible securities, preferred securities and government obligations. The fund may also invest significantly in below-investment-grade bonds (also known as junk bonds) (e.g., high yield bonds or arbitrage and distressed securities), below-investment-grade bank loans, foreign currency denominated bonds and bonds of emerging market issuers. Direct investments in loans may be illiquid and holding a loan could expose the fund to the risks of being a direct lender. The fund's investment in foreign currency-denominated bonds may be on a currency hedged or unhedged basis. Below-investment-grade bonds acquired by the fund directly or through investing in exchange-traded funds (ETFs) and other underlying funds will generally be in the lower categories of the major rating agencies (BB or lower by Standard & Poor's Ratings Services (S&P) or Ba or lower by Moody's Investors Service, Inc. (Moody's)) or, if unrated, will be determined by the management team to be of similar quality. Split-rated bonds will be considered to have the higher credit rating. The fund's investment policies are based on credit ratings at the time of purchase. The average portfolio duration of the fund will vary based on the management team's forecast of interest rates and there are no limits regarding portfolio duration or average maturity.

The fund may invest in common stock, preferred stock, securities convertible into common and preferred stock, and non-convertible preferred stock. The fund generally intends to invest in dividend paying stocks. From time to time, the fund may invest in shares of companies through initial public offerings (IPOs). The fund may invest in securities of both U.S. or foreign issuers without limit, which can be U.S. dollar-based or foreign currency-based and may be currency hedged or unhedged. The fund may invest in securities of companies of any market capitalization.

The fund also may invest extensively in derivative instruments such as futures, options, and swaps, which are generally financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate, or index, and may relate to equity securities, fixed-income securities, interest rates, total return rates, currencies or currency exchange rates, and related hedging purposes. Derivatives may be used to hedge against losses from movements in stock, currency exchange rates or interest rates. Derivatives may be used for non-hedging purposes in order to invest indirectly in securities or financial markets, for duration management which allows the fund to efficiently adjust the average maturity of the

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John Hancock Multi-Asset High Income Fund

fixed-income securities it holds, to gain exposure to foreign currencies, for efficient portfolio management, or to generate additional income for the fund. The fund may also invest in structured notes that provide exposure to derivative instruments. The fund also may invest in restricted or illiquid securities.

The fund writes options on a portion of the value of the fund's portfolio, although this amount is expected to vary over time based upon U.S. and non-U.S. market conditions and other factors. The fund's use of written call options involves a tradeoff between the options premiums received and the reduced participation in potential future security price appreciation of its portfolio. As the seller of call options, the fund receives cash (the premium) from purchasers of the options. The purchaser of a call option has the right to receive from the option seller any appreciation in value over a fixed price (the exercise price) as of a specified date in the future (the option expiration date). In effect, the fund sells the potential appreciation in value, or exercise price, during the term of the option in exchange for the premium. The manager also may cause the fund to sell put options if the manager considers the pricing of those options highly favorable and sale of such an option might beneficially alter the risk profile of the fund's option exposure. The transaction costs of buying and selling options consist primarily of the bid-ask spread and commissions (which are imposed in opening, closing, exercise and assignment transactions), and may include margin and interest costs in connection with both exchange-traded and over-the-counter transactions.

The fund may invest in other investment companies, including ETFs and closed-end funds. In addition, in seeking to achieve its investment objective, the fund may invest directly in, or indirectly through exchange-traded notes (ETNs) and investment companies, including ETFs, that focus their investment strategies on alternative or non-traditional asset categories such as commodities, market neutral (long/short) strategies, global real estate, natural resources, TIPS (Treasury Inflation-Protected Securities), foreign currency trading strategies, managed futures, arbitrage strategies, and tactical, shorter-term investment strategies.

The fund may trade securities actively, which could result in a higher-than-average portfolio turnover rate. The fund may focus its investments in a particular sector or sectors of the economy.

Principal risks

An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Many factors affect performance, and fund shares will fluctuate in price, meaning you could lose money. The fund's investment strategy may not produce the intended results.

During periods of heightened market volatility or reduced liquidity, governments, their agencies, or other regulatory bodies, both within the United States and abroad, may take steps to intervene. These actions, which could include legislative, regulatory, or economic initiatives, might have unforeseeable consequences and could adversely affect the fund's performance or otherwise constrain the fund's ability to achieve its investment objective.

The fund's main risks are listed below in alphabetical order, not in order of importance. Before investing, be sure to read the additional descriptions of these risks beginning on page 8 of the prospectus.

Arbitrage strategies risk. Arbitrage strategies involve engaging in transactions that attempt to exploit the price differences of identical, related, or similar securities within a market or different markets or in different forms. The fund may realize losses or a reduced rate of return if underlying relationships among securities in which it takes investment positions change in an adverse manner or if a transaction is unexpectedly terminated or delayed.

Commodity risk. Commodity prices may be volatile due to fluctuating demand, supply disruption, speculation, and other factors. Certain commodity investments may have no active trading market at times.

Credit and counterparty risk. The issuer or guarantor of a fixed-income security, the counterparty to an over-the-counter derivatives contract, or a borrower of fund securities may not make timely payments or otherwise honor its obligations. U.S. government securities are subject to varying degrees of credit risk depending upon the nature of their support. A downgrade or default affecting any of the fund's securities could affect the fund's performance.

Cybersecurity and operational risk. Cybersecurity breaches may allow an unauthorized party to gain access to fund assets, customer data, or proprietary information, or cause a fund or its service providers to suffer data corruption or lose operational functionality. Similar incidents affecting issuers of a fund's securities may negatively impact performance. Operational risk may arise from human error, error by third parties, communication errors, or technology failures, among other causes.

Distressed investments risk. Distressed investments, including loans, mortgages, bonds, and notes, may not be publicly traded and may involve substantial risk. A fund may lose up to its entire investment.

Economic and market events risk. Events in the U.S. and global financial markets, including actions taken by the U.S. Federal Reserve or foreign central banks to stimulate or stabilize economic growth, may at times result in unusually high market volatility, which could negatively impact performance. Reduced liquidity in credit and fixed-income markets could adversely affect issuers worldwide. Banks and financial services companies could suffer losses if interest rates rise or economic conditions deteriorate.

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John Hancock Multi-Asset High Income Fund

Equity securities risk. The price of equity securities may decline due to changes in a company's financial condition or overall market conditions.

Exchange-traded funds risk. An ETF generally reflects the risks of the underlying securities of the index it is designed to track. However, at times, an ETF's portfolio composition and performance may not match that of such index. A fund bears ETF fees and expenses indirectly.

Exchange-traded notes risk. An ETN generally reflects the risks associated with the assets composing the underlying market benchmark or strategy it is designed to track. ETNs also are subject to issuer and fixed-income risks.

Fixed-income securities risk. A rise in interest rates typically causes bond prices to fall. The longer the average maturity or duration of the bonds held by a fund, the more sensitive it will likely be to interest-rate fluctuations. An issuer may not make all interest payments or repay all or any of the principal borrowed. Changes in a security's credit quality may adversely affect fund performance. Increases in real interest rates generally cause the price of inflation-protected debt securities to decrease.

Foreign securities risk. Less information may be publicly available regarding foreign issuers. Foreign securities may be subject to foreign taxes and may be more volatile than U.S. securities. Currency fluctuations and political and economic developments may adversely impact the value of foreign securities. The risks of investing in foreign securities are magnified in emerging markets. Any depositary receipts are subject to most of the risks associated with investing in foreign securities directly because the value of a depositary receipt is dependent upon the market price of the underlying foreign equity security. Depositary receipts are also subject to liquidity risk.

Hedging, derivatives, and other strategic transactions risk. Hedging, derivatives, and other strategic transactions may increase a fund's volatility and could produce disproportionate losses, potentially more than the fund's principal investment. Risks of these transactions are different from and possibly greater than risks of investing directly in securities and other traditional instruments. Under certain market conditions, derivatives could become harder to value or sell and may become subject to liquidity risk (i.e., the inability to enter into closing transactions). Derivatives and other strategic transactions that the fund intends to utilize include: credit default swaps, foreign currency forward contracts, futures contracts, interest-rate swaps, options. Foreign currency forward contracts, futures contracts, options, and swaps generally are subject to counterparty risk. In addition, swaps may be subject to interest-rate and settlement risk, and the risk of default of the underlying reference obligation. Derivatives associated with foreign currency transactions are subject to currency risk.

High portfolio turnover risk. Trading securities actively and frequently can increase transaction costs (thus lowering performance) and taxable distributions.

Illiquid and restricted securities risk. Illiquid and restricted securities may be difficult to value and may involve greater risks than liquid securities. Illiquidity may have an adverse impact on a particular security's market price and the fund's ability to sell the security.

Initial public offerings risk. IPO share prices are frequently volatile and may significantly impact fund performance.

Investment company securities risk. Underlying fund fees and expenses associated with investments in other investment companies are borne by fund shareholders.

Large company risk. Larger companies may grow more slowly than smaller companies or be slower to respond to business developments. Large-capitalization securities may underperform the market as a whole.

LIBOR discontinuation risk. The publication of the London Interbank Offered Rate (LIBOR), which many debt securities, derivatives and other financial instruments use as the reference or benchmark rate for interest rate calculations, is expected to be discontinued at the end of 2021. The transition process away from LIBOR may lead to increased volatility and illiquidity in markets that currently rely on LIBOR to determine interest rates, and the eventual use of an alternative reference rate may adversely affect the fund's performance. In addition, the usefulness of LIBOR may deteriorate in the period leading up to its discontinuation, which could adversely affect the liquidity or market value of securities that use LIBOR.

Liquidity risk. The extent (if at all) to which a security may be sold or a derivative position closed without negatively impacting its market value may be impaired by reduced market activity or participation, legal restrictions, or other economic and market impediments. Liquidity risk may be magnified in rising interest rate environments due to higher than normal redemption rates. Widespread selling of fixed-income securities to satisfy redemptions during periods of reduced demand may adversely impact the price or salability of such securities. Periods of heavy redemption could cause the fund to sell assets at a loss or depressed value, which could negatively affect performance. Redemption risk is heightened during periods of declining or illiquid markets.

Loan participations risk. Participations and assignments involve special types of risks, including credit risk, interest-rate risk, counterparty risk, liquidity risk, risks associated with extended settlement, and the risks of being a lender.

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John Hancock Multi-Asset High Income Fund

Lower-rated and high-yield fixed-income securities risk. Lower-rated and high-yield fixed-income securities (junk bonds) are subject to greater credit quality risk, risk of default, and price volatility than higher-rated fixed-income securities, may be considered speculative, and can be difficult to resell.

Mortgage-backed and asset-backed securities risk. Mortgage-backed and asset-backed securities are subject to different combinations of prepayment, extension, interest-rate, and other market risks. Factors that impact the value of these securities include interest rate changes, the reliability of available information, credit quality or enhancement, and market perception.

Natural resources industry risk. The natural resources industry can be significantly affected by international political and economic developments, energy conservation and exploration efforts, natural disasters or other extreme weather conditions, commodity prices, and taxes and other governmental regulations, among other factors.

Preferred and convertible securities risk. Preferred stock dividends are payable only if declared by the issuer's board. Preferred stock may be subject to redemption provisions. The market values of convertible securities tend to fall as interest rates rise and rise as interest rates fall. Convertible preferred stock's value can depend heavily upon the underlying common stock's value.

Real estate securities risk. Securities of companies in the real estate industry carry risks associated with owning real estate, including the potential for a decline in value due to economic or market conditions.

Sector risk. When a fund focuses its investments in certain sectors of the economy, its performance may be driven largely by sector performance and could fluctuate more widely than if the fund were invested more evenly across sectors.

Small and mid-sized company risk. Small and mid-sized companies are generally less established and may be more volatile than larger companies. Small and/or mid-capitalization securities may underperform the market as a whole.

Past performance

The following information illustrates the variability of the fund's returns and provides some indication of the risks of investing in the fund by showing changes in the fund's performance from year to year and by showing how the fund's average annual returns compared with a broad-based market index. Past performance (before and after taxes) does not indicate future results. The fund's custom blended benchmark comprises 20% MSCI USA High Dividend Yield Index/ 10% MSCI World ex-USA High Dividend Yield Index/ 25% Bloomberg Barclays US Aggregate Credit - Corporate Investment Grade Index/ 45% Bloomberg Barclays Global High Yield (USD Hedged) Index and shows how the fund's performance compares against the returns of similar investments. All figures assume dividend reinvestment. Performance information is updated daily, monthly, and quarterly and may be obtained at our website, jhinvestments.com, or by calling 800-225-5291 (Class A and Class C), Monday to Thursday, 8:00 A.M.-7:00 P.M., and Friday, 8:00 A.M.-6:00 P.M., Eastern time, or 888-972-8696 (Class I and Class R6) between 8:30 A.M. and 5:00 P.M., Eastern time, on most business days.

Please note that after-tax returns (shown for Class A shares only) reflect the highest individual federal marginal income-tax rate in effect as of the date provided and do not reflect any state or local taxes. Your actual after-tax returns may be different. After-tax returns are not relevant to shares held in an IRA, 401(k), or other tax-advantaged investment plan. The returns for Class A shares have been adjusted to reflect the increase in the maximum sales charge from 4.00% to 4.50% effective May 16, 2020. After-tax returns for other share classes would vary.

Calendar year total returns (%)-Class A (sales charges are not reflected in the bar chart and returns would have been lower if they were)

Year-to-date total return. The fund's total return for the nine months ended September 30, 2020, was -2.06%.
Best quarter:Q1 2019, 6.79%
Worst quarter:Q4 2018, -4.25%

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John Hancock Multi-Asset High Income Fund

Investment management

Investment advisor John Hancock Investment Management LLC
Subadvisor Manulife Investment Management (US) LLC

Portfolio management

Purchase and sale of fund shares

The minimum initial investment requirement for Class A and Class C shares is $1,000 ($250 for group investments), except that there is no minimum for certain group retirement plans, certain fee-based or wrap accounts, or certain other eligible investment product platforms. The minimum initial investment requirement for Class I shares is $250,000, except that the fund may waive the minimum for any category of investors at the fund's sole discretion. The minimum initial investment requirement for Class R6 shares is $1 million, except that there is no minimum for: qualified and nonqualified plan investors; certain eligible qualifying investment product platforms; Trustees, employees of the advisor or its affiliates, employees of the subadvisor, members of the fund's portfolio management team and the spouses and children (under age 21) of the aforementioned. There are no subsequent minimum investment requirements for any of these share classes.

Class A, Class C, Class I, and Class R6 shares may be redeemed on any business day by mail: John Hancock Signature Services, Inc., P.O. Box 219909, Kansas City, MO 64121-9909; or for most account types through our website: jhinvestments.com; or by telephone: 800-225-5291 (Class A and Class C); 888-972-8696 (Class I and Class R6).

Taxes

The fund's distributions are taxable, and will be taxed as ordinary income and/or capital gains, unless you are investing through a tax-deferred arrangement, such as a 401(k) plan or individual retirement account. Withdrawals from such tax-deferred arrangements may be subject to tax at a later date.

Payments to broker-dealers and other financial intermediaries

If you purchase the fund through a broker-dealer or other financial intermediary (such as a bank, registered investment advisor, financial planner, or retirement plan administrator), the fund and its related companies may pay the broker-dealer or other intermediary for the sale of fund shares and

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John Hancock Multi-Asset High Income Fund

related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the fund over another investment. These payments are not applicable to Class R6 shares. Ask your salesperson or visit your financial intermediary's website for more information.

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SEC file number: 811-21779

4480SP 1/1/21 (as revised 7/16/21)