Prospectus Supplement Supplement dated April 15, 2020

Emerging Markets Fund n Emerging Markets Small Cap Fund n Focused Global Growth Fund n Focused International Growth Fund n Global Small Cap Fund n International Growth Fund n International Opportunities Fund n International Value Fund n Non-U.S. Intrinsic Value fund

(Prospectuses dated April 1, 2020)

Global Real Estate Fund n Real Estate Fund n AC Alternatives Income Fund n Growth Fund n Heritage Fund n Select Fund n Small Cap Growth Fund n Sustainable Equity Fund n Ultra Fund n Emerging Markets Debt Fund n Global Bond Fund n International Bond Fund

(Prospectuses dated March 1, 2020)

California High-Yield Municipal Fund n California Intermediate-Term Tax-Free Bond Fund

(Prospectuses dated January 1, 2020)

One Choice^® In Retirement Portfolio n One Choice^® 2020 Portfolio n One Choice^® 2025 Portfolio n One Choice^® 2030 Portfolio n One Choice^® 2035 Portfolio n One Choice^® 2040 Portfolio n One Choice^® 2045 Portfolio n One Choice^® 2050 Portfolio n One Choice^® 2055 Portfolio n One Choice^® 2060 Portfolio n Multi-Asset Income Fund n Strategic Allocation: Aggressive Fund n Strategic Allocation: Conservative Fund n Strategic Allocation: Moderate Fund

(Prospectuses dated December 1, 2019)

Disciplined Growth Fund n Equity Growth Fund n Global Gold Fund n Income & Growth Fund n Multi-Asset Real Return Fund n Small Company Fund

(Prospectuses dated November 1, 2019)

High-Yield Municipal Fund n Intermediate-Term Tax-Free Bond Fund

(Prospectuses dated October 1, 2019)

Ginnie Mae Fund n Government Bond Fund n Inflation-Adjusted Bond Fund n Short-Term Government Fund n AC Alternatives Market Neutral Value Fund n Equity Income Fund n Large Company Value Fund n Mid Cap Value Fund n Small Cap Value Fund n Value Fund n Core Plus Fund n Diversified Bond Fund n High Income Fund n High-Yield Fund n Prime Money Market Fund n Short Duration Fund n Short Duration Inflation Protection Bond Fund n Short Duration Strategic Income Fund n Strategic Income Fund n U.S. Government Money Market Fund

(Prospectuses dated August 1, 2019)

The following replaces the first paragraph in the Account Maintenance Fee section of the prospectuses.

If you hold Investor Class shares of any American Century Investments fund, or I Class shares of the American Century Diversified Bond Fund, in an American Century Investments account (i.e., not through a financial intermediary or employer-sponsored retirement plan account), we may charge you a $25.00 annual account maintenance fee if the value of those shares is less than $10,000. We will determine the amount of your total eligible investments once per year, generally the last Friday in October. If the value of those investments is less than $10,000 at that time, we will automatically redeem shares in one of your accounts to pay the $25.00 fee as soon as administratively possible. Please note that you may incur tax liability as a result of the redemption. In determining your total eligible investment amount, we will include your investments in all personal accounts (including American Century Investments brokerage accounts) registered under your Social Security number. We will not charge the fee as long as you choose to manage your accounts exclusively online. You may enroll for exclusive online account management by visiting americancentury.com. Regardless of whether you manage your account online, you may request a paper copy of the prospectus, statement of additional information, or annual report free of charge.

The following replaces Appendix A in the prospectus for each of the funds.

Appendix A

The information in this Appendix is part of, and incorporated into, the fund’s prospectus.

Financial Intermediary Sales Charge Reduction and Waiver Information

The availability of certain sales charge waivers and discounts will depend on whether you purchase your shares directly from the fund or through a financial intermediary. Intermediaries may have different policies and procedures regarding the availability of front-end sales load waivers or contingent deferred (back-end) sales load (CDSC) waivers, which are set forth below. In all instances, it is the investor’s responsibility to notify the fund or the applicable financial intermediary at the time of purchase of any relationship or other facts qualifying the investor for sales charge waivers or discounts. For waivers and discounts not available through a particular intermediary, shareholders will have to purchase fund shares directly from the fund or through another intermediary to receive these waivers or discounts.

Sales Charge Reductions and Waivers Available through Ameriprise Financial

The following information applies to A Class shares purchases if you have an account with or otherwise purchase fund shares through Ameriprise Financial.

Effective June 1, 2018, shareholders purchasing fund shares through an Ameriprise Financial platform or account will be eligible for the following front-end sales charge waivers and discounts, which may differ from those disclosed elsewhere in this fund’s prospectus or SAI:

• Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs or SAR-SEPs.

• Shares purchased through an Ameriprise Financial investment advisory program (if an advisory or similar share class for such investment advisory program is not available).

• Shares purchased by third party investment advisors on behalf of their advisory clients through Ameriprise Financial’s platform (if an advisory or similar share class for such investment advisory program is not available).

• Shares purchased through reinvestment of distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the American Century Investments family of mutual funds).

• Shares exchanged from C Class shares of the same fund in the month of or following the 10-year anniversary of the purchase date. To the extent that this prospectus elsewhere provides for a waiver with respect to such shares following a shorter holding period, that waiver will apply to exchanges following such shorter period. To the extent that this prospectus elsewhere provides for a waiver with respect to exchanges of C Class shares for load waived shares, that waiver will also apply to such exchanges.

• Employees and registered representatives of Ameriprise Financial or its affiliates and their immediate family members.

• Shares purchased by or through qualified accounts (including IRAs, Coverdell Education Savings Accounts, 401(k)s, 403(b) TSCAs subject to ERISA and defined benefit plans) that are held by a covered family member, defined as an Ameriprise financial advisor and/or the advisor’s spouse, advisor’s lineal ascendant (mother, father, grandmother, grandfather, great grandmother, great grandfather), advisor’s lineal descendant (son, step-son, daughter, step-daughter, grandson, granddaughter, great grandson, great granddaughter) or any spouse of a covered family member who is a lineal descendant.

• Shares purchased from the proceeds of redemptions within the American Century Investments family of mutual funds, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (i.e. Rights of Reinstatement).

Sales Waivers and Reductions in Sales Charges for Edward Jones

Effective on or after May 1, 2020, 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 breakpoints and waivers described elsewhere in the mutual fund 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 American Century or other facts qualifying the purchaser for breakpoints or waivers. Edward Jones can ask for documentation of such circumstance.

Breakpoints

Rights of Accumulation (ROA)

• The applicable sales charge on a purchase of A Class shares is determined by taking into account all share classes (except any money market funds and retirement plan share classes) of American Century held by the shareholder or in an account grouped by Edward Jones with other accounts for the purpose of providing certain pricing considerations ("pricing groups"). This includes all share classes held on the Edward Jones platform and/or held on another platform. The inclusion of eligible fund family assets in the rights of accumulation calculation is dependent on the shareholder notifying his or her financial advisor of such assets at the time of calculation.

• ROA is determined by calculating the higher of cost or market value (current shares x NAV).

Letter of Intent (LOI)

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

Sales Charge Waivers

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

• Associates of Edward Jones and its affiliates and their family members who are in the same pricing group (as determined by Edward Jones under its policies and procedures) as the associate. This waiver will continue for the remainder of the associate's life if the associate retires from Edward Jones in good-standing.

• Shares purchased in an Edward Jones fee-based program.

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment.

• Shares purchased from the proceeds of redeemed shares of the same fund family so long as the following conditions are met: 1) the proceeds are from the sale of shares within 60 days of the purchase, and 2) the sale and purchase 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.

• Shares exchanged into A Class shares from another share class so long as the exchange is into the same fund and was initiated at the discretion of Edward Jones. Edward Jones is responsible for any remaining CDSC due to the fund company, if applicable. Any future purchases are subject to the applicable sales charge as disclosed in the prospectus.

• Exchanges from class C shares to class A shares of the same fund, generally, in the 84th month following the anniversary of the purchase date or earlier at the discretion of Edward Jones.

Contingent Deferred Sales Charge (CDSC) Waivers

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

• The death or disability of the shareholder

• Systematic withdrawals with up to 10% per year of the account value

• Return of excess contributions from an Individual Retirement Account (IRA)

• Shares sold as part of a required minimum distribution for IRA and retirement accounts if the redemption is taken in or after the year the shareholder reaches qualified age based on applicable IRS regulations

• Shares sold to pay Edward Jones fees or costs in such cases where the transaction is initiated by Edward Jones

• Shares exchanged in an Edward Jones fee-based program

• Shares acquired through NAV reinstatement

Other Important Information

1.1 Minimum Purchase Amounts

• $250 initial purchase minimum

• $50 subsequent purchase minimum

1.2 Minimum Balances

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

◦ A fee-based account held on an Edward Jones platform

◦ A 529 account held on an Edward Jones platform

◦ An account with an active systematic investment plan or letter of intent (LOI)

1.3 Changing Share Classes

• At any time it deems necessary, Edward Jones has the authority to exchange at NAV a shareholder's holdings in a fund to Class A shares.

Sales Charge Reductions and Waivers Available through Janney Montgomery Scott LLC (Janney)

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

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

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family).

• Shares purchased by employees and registered representatives of Janney or its affiliates and their family members as designated by Janney.

• Shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within ninety (90) days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (i.e., right of reinstatement).

• Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans.

• Shares acquired through a right of reinstatement.

• C Class shares that are no longer subject to a contingent deferred sales charge and are converted to A Class shares of the same fund pursuant to Janney’s policies and procedures.

CDSC waivers on A and C Class shares available at Janney

• Shares sold upon the death or disability of the shareholder.

• Shares sold as part of a systematic withdrawal plan as described in the fund’s prospectus.

• 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 other retirement accounts if the redemption is taken in or after the year the shareholder reaches qualified age based on applicable IRS regulations.

• Shares sold to pay Janney fees but only if the transaction is initiated by Janney.

• Shares acquired through a right of reinstatement.

• Shares exchanged into the same share class of a different fund.

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

• Breakpoints as described in the fund’s prospectus.

• Rights of accumulation (ROA), 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 Janney. Eligible fund family assets not held at Janney may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets.

• Letters of intent which allow for breakpoint discounts based on anticipated purchases within a fund family, over a 13-month time period. Eligible fund family assets not held at Janney Montgomery Scott may be included in the calculation of letters of intent only if the shareholder notifies his or her financial advisor about such assets.

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

Sales Charge Reductions and Waivers Available through Merrill Lynch

Shareholders purchasing fund shares through a Merrill Lynch platform or account will be eligible only for the following load waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this fund’s prospectus or SAI.

Front-end Sales Load Waivers on A Class Shares available at Merrill Lynch

• Employer-sponsored retirement, deferred compensation and employee benefit plans (including health savings accounts) and trusts used to fund those plans, provided that the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan

• Shares purchased by a 529 Plan (does not include 529-specific share classes or equivalents)

• Shares purchased through a Merrill Lynch affiliated investment advisory program

• Shares exchanged due to the holdings moving from a Merrill Lynch affiliated investment advisory program to a Merrill Lynch brokerage (non-advisory) account pursuant to Merrill Lynch’s policies relating to sales load discounts and waivers

• Shares purchased by third party investment advisors on behalf of their advisory clients through Merrill Lynch’s platform

• Shares of funds purchased through the Merrill Edge Self-Directed platform] (if applicable)

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family)

• Shares exchanged from C Class (i.e. level-load) shares of the same fund pursuant to Merrill Lynch’s policies relating to sales load discounts and waivers

• Employees and registered representatives of Merrill Lynch or its affiliates and their family members

• Directors or trustees of the fund, and employees of the fund’s investment advisor or any of its affiliates, as described in this prospectus

• Eligible shares purchased from the proceeds of redemptions within the American Century Investments family of mutual funds, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (known as Rights of Reinstatement) Automated transactions (i.e. systematic purchases and withdrawals) and purchases made after shares are automatically sold to pay Merrill Lynch’s account maintenance fees are not eligible for reinstatement

CDSC Waivers on A and C Shares available at Merrill Lynch

• Death or disability of the shareholder

• Shares sold as part of a systematic withdrawal plan as described in the fund’s prospectus

• Return of excess contributions from an IRA Account

• Shares sold as part of a required minimum distribution for IRA and retirement accounts pursuant to the Internal Revenue Code

• Shares sold to pay Merrill Lynch fees but only if the transaction is initiated by Merrill Lynch

• Shares acquired through a right of reinstatement

• Shares held in retirement brokerage accounts, that are exchanged for a lower cost share class due to transfer to certain fee based accounts or platforms (applicable to A and C shares only)

• Shares received through an exchange due to the holdings moving from a Merrill Lynch affiliated investment advisory program to a Merrill Lynch brokerage (non-advisory) account pursuant to Merrill Lynch’s policies relating to sales load discounts and waivers

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

• Breakpoints as described in this prospectus.

• 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 (including 529 program holdings, where applicable) within the purchaser’s household at Merrill Lynch. Eligible fund family assets not held at Merrill Lynch may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets

• Letters of Intent (LOI) which allow for breakpoint discounts based on anticipated purchases within a fund family, through Merrill Lynch, over a 13-month period of time (if applicable)

Sales Charge Reductions and Waivers available through Morgan Stanley Wealth Management

Effective July 1, 2018, 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 A Class shares, which may differ from and may be more limited than those disclosed elsewhere in this fund’s prospectus or SAI.

• Employer-sponsored retirement plans (e.g., 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit sharing and money purchase pension plans and defined benefit plans). For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans

• Morgan Stanley employee and employee-related accounts according to Morgan Stanley’s account linking rules

• Shares purchased through reinvestment of dividends and capital gains distributions when purchasing shares of the same fund

• Shares purchased through a Morgan Stanley self-directed brokerage account

• C Class (i.e., level-load) shares that are no longer subject to a contingent deferred sales charge and are converted to A Class shares of the same fund pursuant to Morgan Stanley Wealth Management’s share class conversion program

• Shares purchased from the proceeds of redemptions within the American Century Investments family of mutual funds, 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.

Sales Charge Reductions and Waivers Available through Oppenheimer & Co. Inc. (OPCO)

Effective February 26, 2020, shareholders purchasing fund shares through an OPCO platform or account are eligible only for the following load waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this fund's prospectus or SAL

Front-end Sales Load Waivers on Class A Shares available at OPCO

• Employer-sponsored retirement, deferred compensation and employee benefit plans (including health savings accounts) and trusts used to fund those plans, provided that the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan

• Shares purchased by or through a 529 Plan

• Shares purchased through an OPCO affiliated investment advisory program

• Shares purchased through reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the fund family)

• Shares purchased from the proceeds of redemptions within the same fund family, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (known as Rights of Restatement).

• A shareholder in the fund's C Class shares will have their shares converted at net asset value to A Class shares (or the appropriate share class) of the fund if the shares are no longer subject to a CDSC and the conversion is in line with the policies and procedures of OPCO

• Employees and registered representatives of OPCO or its affiliates and their family members

• Directors or Trustees of the fund, and employees of the fund's investment adviser or any of its affiliates, as described in this prospectus

CDSC Waivers on A and C Shares available at OPCO

• Death or disability of the shareholder

• Shares sold as part of a systematic withdrawal plan as described in the fund's prospectus

• Return of excess contributions from an IRA

• Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable IRS regulations as described in the prospectus

• Shares sold to pay OPCO fees but only if the transaction is initiated by OPCO

• Shares acquired through a right of reinstatement

Front-end load Discounts Available at OPCO: Breakpoints, Rights of Accumulation & Letters of Intent

• Breakpoints as described in this prospectus.

• Rights of Accumulation (ROA) which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of fund family assets held by accounts within the purchaser's household at OPCO. Eligible fund family assets not held at OPCO may be included in the ROA calculation only if the shareholder notifies his or her financial advisor about such assets

Raymond James & Associates, Inc., Raymond James Financial Services & each entity’s affiliates (“Raymond James”)

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

Front-end sales load waivers on Class A shares available at Raymond James

• Shares purchased in an investment advisory program.

• Shares purchased within the same fund family through a systematic reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same fund (but not any other fund within the American Century Investments fund family).

• Employees and registered representatives of Raymond James or its affiliates and their family members as designated by Raymond James.

• Shares purchased from the proceeds of redemptions within the American Century Investments fund family, provided (1) the repurchase occurs within 90 days following the redemption, (2) the redemption and purchase occur in the same account, and (3) redeemed shares were subject to a front-end or deferred sales load (known as Rights of Reinstatement).

• A shareholder in the fund’s C Class shares will have their shares converted at net asset value to A Class 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.

CDSC waivers on A and C Class shares available at Raymond James

• Death or disability of the shareholder.

• Shares sold as part of a systematic withdrawal plan as described in the fund’s prospectus.

• Return of excess contributions from an IRA Account.

• Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the shareholder reaching the qualified age based on applicable IRS regulations as described in the fund’s prospectus.

• Shares sold to pay Raymond James fees but only if the transaction is initiated by Raymond James.

• Shares acquired through a right of reinstatement.

Front-end load discounts available at Raymond James: breakpoints, rights of accumulation, and/or letters of intent

• Breakpoints as described in this prospectus.

• Rights of accumulation which entitle shareholders to breakpoint discounts will be automatically calculated based on the aggregated holding of American Century Investments fund family assets held by accounts within the purchaser’s household at Raymond James. Eligible American Century Investments 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 advisor about such assets.

• 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 advisor about such assets.

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CL-SPL-96153 2004