ck0001710607-20210831

January 1, 2022

American Century Investments
Prospectus

Ticker: Exchange:
American Century® Diversified Municipal Bond ETF
TAXF NYSE Arca, Inc.
























The Securities and Exchange Commission has
not approved or disapproved these securities or
passed upon the adequacy of this prospectus. Any
representation to the contrary is a criminal offense.
ck0001710607-20210831_g1.jpg



Table of Contents
Fund Summary 2 
Investment Objective
Fees and Expenses
Principal Investment Strategies
Principal Risks
Fund Performance
Portfolio Management
Purchase and Sale of Fund Shares
Tax Information
Payments to Broker-Dealers and Other Financial Intermediaries
Objectives, Strategies and Risks 6 
Management 9 
Investing in the Fund 11 
Share Price and Distributions 13 
Taxes 15 
Additional Information 17 
Financial Highlights 18 


















©2022 American Century Proprietary Holdings, Inc. All rights reserved.



Fund Summary
Investment Objective
The fund seeks current income that is exempt from federal income tax.
Fees and Expenses
The following 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.
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Management Fee 0.29%
Other Expenses
0.00%
Total Annual Fund Operating Expenses 0.29%
Example
The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn a 5% return each year, and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
1 year 3 years 5 years 10 years
$30 $93 $163 $369
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 the most recent fiscal year, the fund’s portfolio turnover rate was 14% of the average value of its portfolio.
Principal Investment Strategies
The fund invests in municipal and other debt securities. Under normal market conditions, the portfolio managers invest at least 80% of the fund’s net assets, plus borrowings for investment purposes, in municipal securities with interest payments exempt from federal income tax. Some of these investments in municipal securities are not necessarily exempt from the federal alternative minimum tax.
The fund principally invests in investment-grade debt securities but may invest in high-yield securities (junk bonds). A high-yield security is one that has been rated below investment-grade or determined by the investment advisor to be of similar quality, including bonds that are in technical or monetary default. Issuers of these securities often have short financial histories or have questionable credit or have had and may continue to have problems making interest and principal payments. The portfolio managers also may buy unrated securities if they determine such securities meet the investment objective of the fund.
The fund may purchase debt securities of any duration, and the average duration of the fund will vary based on the portfolio managers’ forecast of interest rates.
Although the fund seeks current income, it also employs techniques designed to realize capital appreciation. For example, the portfolio managers may select bonds with maturities and coupon rates that position the fund for potential capital appreciation for a variety of reasons, including their view on the direction of future interest-rate movements and the potential for a credit upgrade.
The fund is an actively managed exchange-traded fund (ETF) that does not seek to replicate the performance of a specified index. When determining whether to buy or sell a security, portfolio managers consider, among other things, current and anticipated changes in interest rates, the credit quality of a particular issuer, comparable alternatives, general market conditions and any other factor deemed relevant by the portfolio managers.
Principal Risks
Credit Risk - Debt securities, even investment-grade debt securities, are subject to credit risk. The risk that the inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect. The fund’s investments may have high credit risk, which helps the fund pursue a higher yield than more conservatively managed bond funds.
Below Investment-Grade Securities Risk - Issuers of lower rated, high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes, or adverse
2


developments specific to the issuer. Adverse economic, political and other developments may be more likely to cause an issuer of low-quality bonds to default on its obligation to pay interest and principal due under its securities. The fund may invest in securities rated below investment-grade or that are unrated, including bonds that are in technical or monetary default. By definition, the issuers of many of these securities have had and may continue to have problems making interest and principal payments.
Interest Rate Risk - When interest rates change, the fund’s share value will be affected. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. Because the fund may invest in intermediate-term and long-term bonds, the fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
Municipal Securities Risk - Because the fund invests principally in municipal securities, it will be sensitive to events that affect municipal markets, including legislative or political changes and the financial condition of the issuers of municipal securities. The fund may have a higher level of risk than funds that invest in a larger universe of securities. Additionally, the novel coronavirus (COVID -19) pandemic has significantly stressed the financial resources of many municipal issuers, which may impair a municipal issuer’s ability to meet its financial obligations when due and could adversely impact the value of its bonds, which could negatively impact the performance of the fund.
Cash Transactions Risk - The fund may effect its creations and redemptions for cash, rather than for in-kind securities. Therefore, it may be required to sell portfolio securities and subsequently recognize gains on such sales that the fund might not have recognized if it were to distribute portfolio securities in-kind. As such, investments in fund shares may be less tax-efficient than an investment in an ETF that distributes portfolio securities entirely in-kind. Cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. Brokerage fees and taxes will be higher than if the fund sold and redeemed shares in-kind.
Tax Risk - Some or all of the fund’s income may be subject to the federal alternative minimum tax. There is no guarantee that all of the fund’s income will remain exempt from federal or state income taxes. Income from municipal bonds held by a fund could be declared taxable because of unfavorable changes in tax laws, adverse interpretations by the Internal Revenue Service or state tax authorities, or noncompliant conduct of a bond issuer. The fund may sell securities that lose their tax-exempt statuses at inopportune times, which may cause tax consequences or a decrease in the fund’s value.
Liquidity Risk - During periods of market turbulence or unusually low trading activity, to meet redemptions, it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund’s share price. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
Market Trading Risk - The fund faces numerous market trading risks, including the potential lack of an active market for fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation and/or redemption process of the fund. Any of these factors, among others, may lead to the fund’s shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than NAV when you buy shares of the fund in the secondary market, and you may receive less (or more) than NAV when you sell those shares in the secondary market. The portfolio managers cannot predict whether shares will trade above (premium), below (discount) or at NAV.
Market Risk - The risk that the value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
Public Health Emergency Risk - A pandemic, caused by the infectious respiratory illness COVID-19, is causing market disruption and other economic impacts. Markets have experienced volatility, reduced liquidity, and increased trading costs. These events may continue to impact the fund and its underlying investments and could cause increased premiums or discounts to the fund’s NAV.
Authorized Participant Concentration Risk - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund may have a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the fund and no other authorized participant is able to step forward to process creation and/or redemption orders, fund shares may trade at a discount to net asset value (NAV) and possibly face trading halts and/or delisting. This risk may be more pronounced in volatile markets, potentially where there are significant redemptions in ETFs generally.
Large Shareholder Risk - Certain shareholders, including other funds advised by the advisor, may from time to time own a substantial amount of the shares of the fund. In addition, a third party investor, the advisor or an affiliate of the advisor, an authorized participant, a market maker, or another entity may invest in the fund and hold its investment for a limited period of time solely to facilitate commencement of the fund or to facilitate the fund’s achieving a specified size or scale. There can be no assurance that any large shareholder would not redeem its investment, that the size of the fund would be maintained at such levels or that the fund would continue to meet applicable listing requirements. Redemptions by large shareholders could have a significant negative impact on the fund. In addition, transactions by large shareholders may account for a large percentage of the
3


trading volume on the NYSE Arca, Inc. and may, therefore, have a material upward or downward effect on the market price of the shares.
Principal Loss Risk - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.
An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
Fund Performance
The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancenturyetfs.com.
Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.
Calendar Year Total Returns
ck0001710607-20210831_g3.jpg
Highest Performance Quarter (2Q 2020): 3.62% Lowest Performance Quarter (1Q 2020): -2.74%
As of September 30, 2021, the most recent calendar quarter end, the fund’s year-to-date return was 1.96%.
Average Annual Total Returns
For the calendar year ended December 31, 2020
1 year Since Inception Inception Date
American Century Diversified Municipal Bond ETF Shares
Return Before Taxes 5.47% 6.36% 09/10/2018
Return After Taxes on Distributions 5.47% 6.36% 09/10/2018
Return After Taxes on Distributions and Sale of Fund Shares 4.15% 5.46% 09/10/2018
S&P National AMT-Free Municipal Bond Index
  (reflects no deduction for fees, expenses or taxes)
4.95% 5.88% 09/10/2018
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

4


Portfolio Management
Investment Advisor
American Century Investment Management, Inc.
Portfolio Managers
Steven M. Permut, Senior Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments for American Century Investments since joining the advisor in 1987.
Joseph Gotelli, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments for American Century Investments since joining the advisor in 2008.
Alan Kruss, Vice President and Portfolio Manager, has served on teams managing fixed-income investments for American Century Investments since joining the advisor in 1997.
Purchase and Sale of Fund Shares
The fund is an ETF. Fund shares may only be bought and sold in a secondary market through a broker-dealer at a market price. Because ETF shares trade at market prices rather than NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). An investor may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the fund (bid) and the lowest price a seller is willing to accept for shares of the fund (ask) when buying or selling shares in the secondary market (bid-ask spread). Investors can find information on the fund’s NAV, market price, premiums and discounts, and bid-ask spread at americancenturyetfs.com.
Tax Information
The fund intends to distribute income that is exempt from regular federal income tax, however, fund distributions may be subject to capital gains tax. A portion of the fund’s distributions may be subject to federal income tax or to the federal alternative minimum tax.
If you hold your fund shares through a tax-deferred investment plan, such as a 401(k) plan or an IRA, any distributions received from the fund may be taxable as ordinary income upon withdrawal from the tax-deferred plan, regardless of whether the distributions were tax-exempt when earned.
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), the advisor and its related companies may pay the intermediary for the sale of fund shares and 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. Ask your salesperson or visit your financial intermediary’s website for more information.
5


Objectives, Strategies and Risks
What are the fund’s investment objectives?
The fund seeks current income that is exempt from federal income tax.
The fund’s investment objective is a nonfundamental investment policy and may be changed by the Board of Trustees without approval by shareholders.
What are the fund’s principal investment strategies?
Under normal market conditions, the portfolio managers invest at least 80% of the fund’s net assets, plus borrowings for investment purposes, in municipal securities with interest payments exempt from federal income tax. The fund may change this 80% policy only upon 60 days’ prior written notice to shareholders. A municipal security is a debt obligation issued by or on behalf of a state, its political subdivisions, agencies or instrumentalities, the District of Columbia or a U.S. territory or possession. Cities, counties and other municipalities in the 50 states and U.S. territories usually issue these securities for public projects, such as schools, roads and other public infrastructure projects.
The portfolio managers also may buy debt securities with interest payments exempt from federal income tax, but not exempt from the federal alternative minimum tax. Cities, counties and other municipalities usually issue these securities (called private activity bonds) to fund for-profit private projects, such as airports and athletic stadiums.
The portfolio managers may buy securities that are rated below investment-grade, including so-called junk bonds and bonds that are in technical or monetary default. Issuers of these securities often have short financial histories or have questionable credit or have had and may continue to have problems making interest and principal payments. The portfolio managers also may buy unrated securities if they determine such securities meet the investment objectives of the fund.
The fund may purchase debt securities of any duration, and the average duration of the fund will vary based on the portfolio managers’ forecast of interest rates. Duration is an indication of the relative sensitivity of a security’s market value to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Duration is different from maturity in that it attempts to measure the interest rate sensitivity of a security, as opposed to its expected final maturity.
Although the fund seeks current income, it also employs techniques designed to realize capital appreciation. For example, the portfolio managers may select bonds with maturities and coupon rates that position the fund for potential capital appreciation for a variety of reasons, including their view on the direction of future interest-rate movements and the potential for a credit upgrade.
In the event of exceptional market or economic conditions, the fund may take temporary defensive positions that are inconsistent with the fund’s principal investment strategies. To the extent the fund assumes a defensive position, it may not achieve its investment objective.
The fund is an actively managed ETF that does not seek to replicate the performance of a specified index. When determining whether to sell a security, the portfolio manager considers, among other things, current and anticipated changes in interest rates, the credit quality of a particular issuer, comparable alternatives, general market conditions and any other factor deemed relevant by the portfolio manager.
A description of the policies and procedures with respect to the disclosure of the fund’s portfolio securities is available in the statement of additional information. Portfolio holdings can be viewed online at americancenturyetfs.com.
What are the principal risks of investing in the fund?
Credit Risk - Credit risk is the risk that the inability or perceived inability of the issuer to make interest and principal payments will cause the value of the securities to decrease. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect. A high credit rating indicates a high degree of confidence by the rating organization that the issuer will be able to withstand adverse business, financial or economic conditions and make interest and principal payments on time. A lower credit rating indicates a greater risk of nonpayment. Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to the issuer. In addition, lower-rated securities may be unsecured or subordinated to other obligations of the issuer. These factors may be more likely to cause an issuer of low-quality bonds to default on its obligation to pay interest and principal due under its securities. The fund’s credit quality restrictions apply at the time of purchase; the fund will not necessarily sell securities if they are downgraded by a rating agency.
Below Investment-Grade Securities Risk - Issuers of lower rated, high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes, or adverse developments specific to the issuer. Adverse economic, political and other developments may be more likely to cause an issuer of low-quality bonds to default on its obligation to pay interest and principal due under its securities. The fund may invest in securities rated below investment-grade or that are unrated, including bonds that are in technical or monetary default. By definition, the issuers of many of these securities have had and may continue to have problems making interest and principal payments.
6


Interest Rate Risk - Investments in debt securities are also sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. The degree to which interest rate changes affect the fund’s performance varies and is related to the weighted average maturity of the fund. For example, when interest rates rise, you can expect the share value of a long-term bond fund to fall more than that of a short-term bond fund. When rates fall, the opposite is true. Because the fund may invest in intermediate-term and long-term bonds, the fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
Municipal Securities Risk - Because the fund invests principally in municipal securities, it will be sensitive to events that affect municipal markets, including legislative or political changes and the financial condition of the issuers of municipal securities. The fund may have a higher level of risk than funds that invest in a larger universe of securities. Additionally, the novel coronavirus (COVID -19) pandemic has significantly stressed the financial resources of many municipal issuers, which may impair a municipal issuer’s ability to meet its financial obligations when due and could adversely impact the value of its bonds, which could negatively impact the performance of the fund.
Cash Transactions Risk - ETFs generally are able to make in-kind redemptions and avoid being taxed on gain on the distributed portfolio securities at the fund level. However, because the fund may effect redemptions in cash, rather than in-kind, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. If the fund recognizes gain on these sales, this generally will cause the fund to recognize gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The fund generally intends to distribute these gains to shareholders to avoid being taxed on this gain at the fund level and otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains they would not otherwise be subject to, or at an earlier date than, if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid and may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which may be higher than if the fund sold and redeemed its shares in-kind, will be passed on to purchasers and redeemers of Creation Units in the form of creation and redemption transaction fees. To the extent that these costs are not offset by a transaction fee, the fund may bear the expense.
Tax Risk - Some or all of the fund’s income may be subject to the federal alternative minimum tax. There is no guarantee that all of the fund’s income will remain exempt from federal or state income taxes. Income from municipal bonds held by a fund could be declared taxable because of unfavorable changes in tax laws, adverse interpretations by the Internal Revenue Service or state tax authorities, or noncompliant conduct of a bond issuer. The fund may sell securities that lose their tax-exempt statuses at inopportune times, which may cause tax consequences or a decrease in the fund’s value. Some or all of the fund’s income may be subject to the federal alternative minimum tax. For more information, see Taxes in this prospectus.
Liquidity Risk - The chance that a fund will have difficulty selling its debt securities is called liquidity risk. During periods of market turbulence or unusually low trading activity, in order to meet redemptions it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund’s share price. The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Adverse publicity and investor perceptions, as well as new and proposed laws, also may have a greater negative impact on the market for lower-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
Market Trading Risk - Although shares of the fund are listed for trading on one or more stock exchanges, there can be no assurance that an active trading market for such shares will develop or be maintained. There are no obligations of market makers to make a market in the fund’s shares or of an authorized participant to submit purchase or redemption orders for Creation Units. Decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of the fund’s portfolio securities and the fund’s market price. This reduced effectiveness could result in fund shares trading at a premium or discount to its NAV and also greater than normal intraday bid/ask spreads.
Shares of the fund may trade in the secondary market at times when the fund does not accept orders to purchase or redeem shares. At such times, shares may trade in the secondary market with more significant premiums or discounts than might be experienced at times when the fund accepts purchase and redemption orders. Secondary market trading in fund shares may be halted by a stock exchange because of market conditions or other reasons, and may be subject to trading halts caused by extraordinary market volatility pursuant to “circuit breaker” rules on the stock exchange or market. There can be no assurance that the requirements necessary to maintain the listing or trading of fund shares will continue to be met or will remain unchanged. In addition, during a “flash crash,” the market prices of the fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the fund. Flash crashes may cause authorized participants and other market makers to limit or cease trading in the fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell fund shares at these temporarily low market prices.
7


Shares of the fund may trade at prices other than NAV. Thus, you may pay more (or less) than NAV when you buy shares of the fund in the secondary market, and you may receive less (or more) than NAV when you sell those shares in the secondary market. While the creation/redemption feature is designed to make it likely that the fund’s shares normally will trade on stock exchanges at prices close to the fund’s next calculated NAV, market prices are not expected to correlate exactly with the fund’s NAV due to timing reasons as well as market supply and demand factors. In addition, disruptions to creations and redemptions or extreme market volatility may result in trading prices for shares of the fund that differ significantly from its NAV. The portfolio managers cannot predict whether shares will trade above (premium), below (discount) or at NAV.
When buying or selling shares of the fund through a broker, you will likely incur a brokerage commission or other charges determined by your broker. In addition, you may incur the cost of the “spread,” that is, any difference between the bid price and the ask price. The spread varies over time for shares of the fund based on the fund’s trading volume and market liquidity, and is generally lower if the fund has a lot of trading volume and market liquidity, and higher if the fund has little trading volume and market liquidity. During times of market stress, spreads may widen causing investors to pay more.
Market Risk - The risk that the value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
Public Health Emergency Risk - A pandemic, caused by the infectious respiratory illness COVID-19, is causing travel restrictions, disruption of healthcare systems, prolonged quarantines, cancellations, supply chain interruptions, lower consumer demand, layoffs, credit downgrades, and defaults among other economic impacts. Certain markets have experienced temporary closures, extreme volatility, losses, reduced liquidity and increased trading costs. These events may continue to impact the fund and its underlying investments and could cause increased premiums or discounts to the fund’s NAV.
Authorized Participant Concentration Risk - Only an authorized participant may engage in creation or redemption transactions directly with the fund. The fund may have a limited number of institutions that act as authorized participants, none of which are obligated to engage in creation or redemption transactions. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the fund and no other authorized participant is able to step forward to process creation and/or redemption orders, fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. This risk may be more pronounced in volatile markets, potentially where there are significant redemptions in ETFs generally. Authorized participant concentration risk may be heightened in scenarios where authorized participants have limited or diminished access to the capital required to post collateral.
Large Shareholder Risk - Certain shareholders, including other funds advised by the advisor, may from time to time own a substantial amount of the shares of the fund. In addition, a third party investor, the advisor or an affiliate of the advisor, an authorized participant, a market maker, or another entity may invest in the fund and hold its investment for a limited period of time solely to facilitate commencement of the fund or to facilitate the fund’s achieving a specified size or scale. There can be no assurance that any large shareholder would not redeem its investment, that the size of the fund would be maintained at such levels or that the fund would continue to meet applicable listing requirements. Redemptions by large shareholders could have a significant negative impact on the fund. In addition, transactions by large shareholders may account for a large percentage of the trading volume on the NYSE Arca, Inc. and may, therefore, have a material upward or downward effect on the market price of the shares.
Principal Loss Risk - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

8


Management
Who manages the fund?
The Board of Trustees, investment advisor and fund management team play key roles in the management of the fund.
The Board of Trustees
The Board of Trustees is responsible for overseeing the advisor’s management and operations of the fund pursuant to the management agreement. In performing their duties, Board members receive detailed information about the fund and its advisor regularly throughout the year, and meet at least quarterly with management of the advisor to review reports about fund operations. The trustees’ role is to provide oversight and not to provide day-to-day management. The majority of the trustees are independent of the fund’s advisor. They are not employees, directors or officers of, and have no financial interest in, the advisor or any of its affiliated companies (other than as shareholders of American Century Investments funds), and they do not have any other affiliations, positions or relationships that would cause them to be considered “interested persons” under the Investment Company Act of 1940 (Investment Company Act).
The Investment Advisor
The fund’s investment advisor is American Century Investment Management, Inc. (the advisor). The advisor has been managing investment companies since 1958 and is headquartered at 4500 Main Street, Kansas City, Missouri 64111.
The advisor is responsible for managing the investment portfolio of the fund and directing the purchase and sale of its investment securities. The advisor also arranges for transfer agency, custody and all other services necessary for the fund to operate.
For the services it provides to the fund, the advisor receives a unified management fee based on a percentage of the daily net assets of the fund. The amount of the fee is calculated daily and paid monthly in arrears. The advisor pays all expenses of managing and operating the fund, other than the management fee payable to the advisor, brokerage and other transaction fees and expenses relating to the acquisition and disposition of portfolio securities, acquired fund fees and expenses, interest, taxes, litigation expenses, extraordinary expenses, and expenses incurred in connection with the provision of shareholder and distribution services under a plan adopted pursuant to Rule 12b-1 under the Investment Company Act (if any). The advisor may pay unaffiliated third parties who provide recordkeeping and administrative services that would otherwise be performed by an affiliate of the advisor.
Management Fees Paid by the Fund to the Advisor As a Percentage of Average
Net Assets for the Fiscal Year Ended August 31, 2021
American Century Diversified Municipal Bond ETF 0.29%
A discussion regarding the basis for the Board of Trustees’ approval of the fund’s investment advisory agreement with the advisor is available in the fund’s annual report to shareholders for the fiscal year ended August 31, 2021.
The Fund Management Team
The advisor uses teams of portfolio managers and analysts, organized by broad investment categories such as money markets, corporate bonds, government bonds and municipal bonds, in its management of fixed-income funds. Designated portfolio managers serve on the firm’s Global Fixed Income Investment Committee, which is responsible for periodically adjusting the fund’s dynamic investment parameters based on economic and market conditions. The fund’s portfolio managers are responsible for security selection and portfolio construction for the fund within these parameters, as well as compliance with stated investment objectives and cash flow monitoring. Other members of the investment team provide research and analytical support but generally do not make day-to-day investment decisions for the fund.
The individuals listed below are jointly and primarily responsible for the day-to-day management of the fund described in this prospectus. 
Steven M. Permut (Global Fixed Income Investment Committee Representative)
Mr. Permut, Senior Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments since joining the advisor in 1987. He has a bachelor’s degree in business and geography from State University of New York – Oneonta and an MBA in finance from Golden Gate University – San Francisco.
Joseph Gotelli
Mr. Gotelli, Vice President and Senior Portfolio Manager, has served on teams managing fixed-income investments since joining the advisor in 2008. He has a bachelor’s degree in business economics from the University of California, Santa Barbara and an MBA from Santa Clara University.
Alan Kruss
Mr. Kruss, Vice President and Portfolio Manager, has served on teams managing fixed-income investments since joining the advisor in 1997. He has a bachelor’s degree in finance from San Francisco State University.
The statement of additional information provides additional information about the accounts managed by the portfolio managers, the structure of their compensation, and their ownership of fund securities.
9


Fundamental Investment Policies
Shareholders must approve any change to the fundamental investment policies contained in the statement of additional information. The Board of Trustees and/or the advisor may change any other policies, including the fund’s investment objective, or investment strategies described in this prospectus or otherwise used in the operation of the fund at any time, subject to applicable notice provisions.

10


Investing in the Fund
Buying and Selling Shares
Shares of the fund may be acquired or redeemed directly from the fund only in Creation Units or multiples thereof, as discussed below. Only an authorized participant may engage in creation and redemption transactions directly with the fund. Once created, shares of the fund generally trade in the secondary market in amounts less than a Creation Unit.
Shares of the fund are listed on a national securities exchange for trading during the trading day. Shares can be bought and sold throughout the trading day like shares of other publicly traded companies. American Century ETF Trust (the trust) does not impose any minimum investment for shares of the fund purchased on an exchange. Shares of the fund trade under the following ticker symbol: TAXF.
Buying or selling fund shares on an exchange involves two types of costs that may apply to all securities transactions. When buying or selling shares of the fund through a broker, you will likely incur a brokerage commission or other charges determined by your broker. The commission is frequently a fixed amount and may be a significant proportional cost for investors seeking to buy or sell small amounts of shares. In addition, you may incur the cost of the “spread,” that is, any difference between the bid price and the ask price. The spread varies over time for shares of the fund based on the fund’s trading volume and market liquidity, and is generally lower if the fund has a lot of trading volume and market liquidity, and higher if the fund has little trading volume and market liquidity.
The fund’s primary listing exchange is NYSE Arca, Inc., which is open for trading Monday through Friday and is closed on weekends and the following holidays: New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Juneteenth National Independence Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day.
Book Entry
Shares of the fund are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company (DTC) or its nominee is the record owner of all outstanding shares of the fund and is recognized as the owner of all shares for all purposes.
Investors owning shares of the fund are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for shares of the fund. DTC participants include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of stock certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other securities that you hold in book-entry or “street name” form.
Frequent Trading Practices
The Board of Trustees has not adopted a policy of monitoring for frequent purchases and redemptions of fund shares (frequent trading). The Board of Trustees believes that a frequent trading policy is unnecessary because fund shares are listed for trading on a national securities exchange. Therefore, it is unlikely that a shareholder could take advantage of a potential arbitrage opportunity presented by a lag between a change in the value of the fund’s portfolio securities after the close of the primary markets for the fund’s portfolio securities and the reflection of that change in the fund’s NAV (market timing), because the fund generally sells and redeems its shares directly through transactions that are in-kind and/or for cash, subject to the conditions described below under Creations and Redemptions.
Investments by Other Investment Companies
Section 12(d)(1) of the Investment Company Act restricts investments by investment companies in the securities of other investment companies. Registered investment companies are permitted to invest in the fund beyond the limits set forth in Section 12(d)(1), subject to certain terms and conditions set forth in SEC rules. In order for an unaffiliated registered investment company to invest in shares of the fund beyond the limitations of Section 12(d)(1) pursuant to Rule 12d1-4, the registered investment company must enter into an agreement with the trust.
Creations and Redemptions
Prior to trading in the secondary market, shares of the fund are “created” at NAV by market makers, large investors and institutions only in block-size units, called “Creation Units.” All orders to purchase Creation Units must be placed by or through an authorized participant that has entered into an authorized participant agreement (AP Agreement) with Foreside Fund Services, LLC (the distributor). Only an authorized participant may create or redeem Creation Units directly with the fund.
A creation transaction, which is subject to acceptance by the trust, generally takes place when an authorized participant deposits into the fund a designated portfolio of securities and/or cash (which may include cash in lieu of certain securities) in exchange for a specified number of Creation Units. With respect to the fund, these deposits are generally in cash. Similarly, shares can be redeemed only in Creation Units, generally for a designated portfolio of securities and/or cash (which may include cash in lieu of certain
11


securities). With respect to the fund, redemptions are generally on an in-kind basis, but the fund reserves the right to meet redemptions in cash. Except when aggregated in Creation Units, shares are not redeemable by the fund.
The prices at which creations and redemptions occur are based on the next calculation of NAV after a creation or redemption order is received in a proper form under the AP Agreement. The portfolio of securities required for purchase of a Creation Unit is generally the same as the portfolio of securities the fund will deliver upon redemption of fund shares, except under certain circumstances. As a result of any system failure or other interruption, creation or redemption orders either may not be executed according to the fund’s instructions or may not be executed at all, or the fund may not be able to place or change such orders.
Creations and redemptions must be made through a firm that is either a broker-dealer or other participant in the Continuous Net Settlement System of the National Securities Clearing Corporation or a DTC participant and, in either case, has executed an AP Agreement with the distributor. Information about the procedures regarding creations and redemptions of Creation Units (including the cut-off times for receipt of creation and redemption orders) is included in the fund’s statement of additional information (SAI).
Because new shares may be created and issued on an ongoing basis, at any point during the life of the fund a “distribution,” as such term is used in the Securities Act of 1933 (Securities Act), may be occurring. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner that could render them statutory underwriters and subject to the prospectus delivery and liability provisions of the Securities Act. Any determination of whether one is an underwriter must take into account all the relevant facts and circumstances of each particular case.
Broker-dealers should also note that dealers who are not “underwriters” but are participating in a distribution (as contrasted to ordinary secondary transactions), and thus dealing with shares that are part of an “unsold allotment” within the meaning of Section 4(a)(3)(C) of the Securities Act, would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. For delivery of prospectuses to exchange members, the prospectus delivery mechanism of Rule 153 under the Securities Act is available only with respect to transactions on a national securities exchange.
In addition, certain affiliates of the fund and the advisor may purchase and resell fund shares pursuant to this prospectus.

12


Share Price and Distributions
Share Price
The price of fund shares is based on market price. The trading prices of the fund’s shares in the secondary market generally differ from the fund’s daily NAV and are affected by market forces such as supply and demand, economic conditions and other factors.
Calculation of NAV
American Century Investments will price the fund shares purchased or redeemed by authorized participants based on the net asset value (NAV) next determined after an order is received in good order by the fund’s transfer agent. We determine the NAV of the fund as of the close of regular trading (usually 4 p.m. Eastern time) on the New York Stock Exchange (NYSE) on each day the NYSE is open. On days when the NYSE is closed (including certain U.S. national holidays), we do not calculate the NAV.
The net asset value, or NAV, of the fund is the current value of the fund’s assets, minus any liabilities, divided by the number of shares of the fund outstanding.
Readily available market quotations for fixed-income securities shall generally be received from independent pricing services that have been approved by the Board. It is anticipated that such pricing services will generally provide evaluated prices based on accepted industry conventions. Evaluated prices are commonly derived through utilization of market models. Such models take into consideration various market factors and security characteristics. These may include, but are not limited to, the following: trade data, quotations from broker-dealers and active market makers, relevant yield curve and spread data, related sector levels, creditworthiness, trade data or market information on comparable securities and other relevant security specific information. Debt obligations with 60 days or less remaining until maturity may be valued at amortized cost.
If the fund determines that the market price for a portfolio security is not readily available or that the valuation methods mentioned above do not reflect the security’s fair value, such security is valued as determined in good faith by the fund’s board or its designee, in accordance with procedures adopted by the fund’s board. Circumstances that may cause the fund to use alternate procedures to value a security include, but are not limited to:
if, after the close of the foreign exchange on which a portfolio security is principally traded, but before the close of the NYSE, an event occurs that may materially affect the value of the security;
a debt security has been declared in default; or
trading in a security has been halted during the trading day.
If such circumstances occur, the fund will fair value the security if the fair valuation would materially impact the fund’s NAV. While fair value determinations involve judgments that are inherently subjective, these determinations are made in good faith in accordance with procedures adopted by the fund’s board.
The effect of using fair value determinations is that the fund’s NAV will be based, to some degree, on security valuations that the board or its designee believes are fair rather than being solely determined by the market.
With respect to any portion of the fund’s assets that are invested in one or more open-end management investment companies that are registered with the SEC (known as registered investment companies), the fund’s NAV will be calculated based upon the NAVs of such registered investment companies. These registered investment companies are required by law to explain the circumstances under which they will use fair value pricing and the effects of using fair value pricing in their prospectuses.
Trading of securities in foreign markets may not take place every day the NYSE is open. Also, trading in some foreign markets and on some electronic trading networks may take place on weekends or holidays when the fund’s NAV is not calculated. So, the value of the fund’s portfolio may be affected on days when you will not be able to purchase or sell fund shares.
Distributions
Federal tax laws require the fund to make distributions to its shareholders to qualify as a regulated investment company. Qualification as a regulated investment company means the fund should not be subject to state or federal income tax on amounts distributed. The distributions generally consist of dividends and interest received by the fund, as well as capital gains realized by the fund on the sale of its investment securities.
Capital gains are increases in the values of capital assets, such as stocks or bonds, from the time the assets are purchased.
The fund generally expects to pay distributions from net income, if any, monthly. The fund generally pays distributions from realized capital gains, if any, once a year. It may make more frequent distributions if necessary to comply with Internal Revenue Code provisions. The fund intends to designate distributions from net income as exempt-interest dividends. To be eligible to make this designation, at least 50% of the value of the fund’s total assets must consist of tax-exempt interest obligations at the close of each quarter.
13


Although dividends generally will be treated as distributed when paid, any dividend declared by a fund in October, November or December and payable to shareholders of record in such a month that is paid during the following January will be treated for U.S. federal income tax purposes as received by shareholders on December 31 of the calendar year in which it was declared.
Dividend payments are made through DTC participants and indirect participants to beneficial owners then of record with proceeds received from the fund. Distributions may be automatically reinvested in whole fund shares only if you purchased the shares through a broker that makes such option available.

14


Taxes
Some of the tax consequences of owning shares of the fund will vary depending on whether you own them through a taxable or tax-deferred account. Distributions by the fund of dividend and interest income, capital gains and other income it has generated through its investment activities will generally be taxable to shareholders who hold shares in a taxable account. Tax consequences also may result when investors sell fund shares.
Tax-Exempt Income
Most of the income that the fund receives from municipal securities is exempt from regular federal income taxes. However, income tax exempt from federal tax may be subject to state and local income tax.
The fund also may purchase private activity bonds. The income from these securities is subject to the federal alternative minimum tax. If you are subject to the alternative minimum tax, distributions from the fund that represent income derived from private activity bonds are taxable to you. Consult your tax advisor to determine whether you are subject to the alternative minimum tax.
Taxable Income
The fund’s investment performance also is based on sources other than income from municipal securities. These investment performance sources, while not the primary source of fund distributions, will generate taxable income to you. Some of these investment performance sources are:
Market Discount Purchases. The fund may buy a tax-exempt security for a price less than the principal amount of the bond. If the price of the bond increases over time, a portion of the gain may be treated as ordinary income and will be taxable as ordinary income if it is distributed to shareholders.
Capital Gains. When the fund sells a security, even a tax-exempt municipal security, it can generate a capital gain or loss, which you must report on your tax return.
Temporary Investments. Some temporary investments, such as securities loans and repurchase agreements, can generate taxable income.
Taxability of Distributions
Fund distributions may consist of income, such as dividends and interest earned by the fund from its investments, or capital gains generated by the fund from the sale of investment securities. Distributions of income are generally exempt form regular federal income tax. However, if distributions are federally taxable, such distributions may be designated as qualified dividend income. If so, and if you meet a minimum required holding period with respect to your shares of the fund, such distributions of income are taxed at the same rates as long-term capital gains.
Qualified dividend income is a dividend received by a fund from the stock of a domestic or qualifying foreign corporation, provided that the fund has held the stock for a required holding period and the stock was not on loan at the time of the dividend.
The tax character of any distributions from capital gains is determined by how long the fund held the underlying security that was sold, not by how long you have been invested in the fund or whether you reinvest your distributions or take them in cash. Short-term (one year or less) capital gains are taxable as ordinary income. Gains on securities held for more than one year are taxed at the lower rates applicable to long-term capital gains.
If a fund’s distributions exceed current and accumulated earnings and profits, such excess will generally be considered a return of capital. A return of capital distribution is generally not subject to tax, but will reduce your cost basis in the fund and result in higher realized capital gains (or lower realized capital losses) upon the sale of fund shares.
You will receive information regarding the tax character of fund distributions for each calendar year in an annual tax mailing.
If you meet specified income levels, you will also be subject to a 3.8% Medicare contribution tax which is imposed on net investment income, including interest, dividends and capital gains. This tax is not imposed on tax-exempt interest.
If you hold your fund shares through a tax-deferred investment plan, such as a 401(k) plan or an IRA, any distributions received from the fund may be taxable as ordinary income upon withdrawal from the tax-deferred plan, regardless of whether the distributions were tax-exempt when earned.
Distributions also may be subject to state and local taxes. Because everyone’s tax situation is unique, you may want to consult your tax professional about federal, state and local tax consequences.
Taxes on Transactions
Your sales of fund shares are subject to capital gains tax. Short-term capital gains are gains on fund shares you held for 12 months or less. Long-term capital gains are gains on fund shares you held for more than 12 months. If your shares decrease in value, their sale will result in a long-term or short-term capital loss. However, you should note that loss realized upon the sale of shares held for six months or less will be treated as a long-term capital loss to the extent of any distribution of long-term capital gain to you with respect
15


to those shares. If a loss is realized on the sale of fund shares, the reinvestment in additional fund shares within 30 days before or after the sale may be subject to the wash sale rules of the Internal Revenue Code. This may result in a postponement of the recognition of such loss for federal income tax purposes.
If you have not certified that your Social Security number or tax identification number is correct and that you are not subject to withholding, you may be subject to backup withholding at the applicable federal withholding tax rate on to taxable dividends, capital gains distributions and proceeds from the sale of fund shares.
Taxes on Creations and Redemptions of Creation Units
An Authorized Participant who exchanges securities for Creation Units generally will recognize a gain or a loss equal to the difference between the market value of the Creation Units at the time and the sum of the exchanger’s aggregate basis in the securities surrendered plus the amount of cash paid for such Creation Units. A person who redeems Creation Units will generally recognize a gain or loss equal to the difference between the exchanger’s basis in the Creation Units and the sum of the aggregate market value of any securities received plus the amount of any cash received for such Creation Units. The IRS, however, may assert that a loss realized upon an exchange of securities for Creation Units cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.
Any capital gain or loss realized upon the creation of Creation Units will generally be treated as long-term capital gain or loss if the securities exchanged for such Creation Units have been held for more than one year. Any capital gain or loss realized upon the redemption of Creation Units will generally be treated as long-term capital gain or loss if the shares comprising the Creation Units have been held for more than one year. Otherwise, such capital gains or losses will generally be treated as short-term capital gain or loss. Any loss upon a redemption of Creation Units held for six months or less will be treated as a long-term capital loss to the extent of any amounts treated as distributions to the applicable Authorized Participant of long-term capital gain with respect to the Creation Units (including any amounts credited to the Authorized Participant as undistributed capital gains).
If a fund redeems Creation Units in cash, it may recognize more capital gains than it will if it redeems Creation Units in-kind.
Buying a Dividend
Purchasing fund shares in a taxable account shortly before a distribution is sometimes known as buying a dividend. In taxable accounts, you must pay income taxes on the distribution whether you reinvest the distribution or take it in cash. In addition, you will have to pay taxes on the distribution whether the value of your investment decreased, increased or remained the same after you bought the fund shares.
The risk in buying a dividend is that a fund’s portfolio may build up taxable income and gains throughout the period covered by a distribution, as income is earned and securities are sold at a profit. The fund distributes the income and gains to you, after subtracting any losses, even if you did not own the shares when the income was earned or the gains occurred.
If you buy a dividend, you incur the full tax liability of the distribution period, but you may not enjoy the full benefit of the income earned or the gains realized in the fund’s portfolio.

16


Additional Information
Service, Distribution and Administrative Fees
Investment Company Act Rule 12b-1 permits investment companies that adopt a written plan to pay certain expenses associated with the distribution of their shares out of fund assets. The Board of Trustees has adopted a 12b-1 plan that allows the fund to pay annual fees not to exceed 0.25% to the distributor for distribution and individual shareholder services. However, the Board of Trustees has determined not to authorize payment of a 12b-1 plan fee at this time.
Because these fees may be used to pay for services that are not related to prospective sales of the fund, to the extent that a fee is authorized, the fund will continue to make payments under its plan even if it is closed to new investors. Because these fees are paid out of the fund’s assets on an ongoing basis, to the extent that a fee is authorized, over time these fees will increase the cost of your investment and may cost you more than paying other types of sales charges.
The advisor or its affiliates may make payments to intermediaries for various additional services, other expenses and/or the intermediaries’ distribution of the fund out of their profits or other available sources. Such payments may be made for one or more of the following: (1) distribution, which may include expenses incurred by intermediaries for their sales activities with respect to the fund, such as preparing, printing and distributing sales literature and advertising materials and compensating registered representatives or other employees of such financial intermediaries for their sales activities, as well as the opportunity for the fund to be made available by such intermediaries; (2) shareholder services, such as providing individual and custom investment advisory services to clients of the financial intermediaries; and (3) marketing and promotional services, including business planning assistance, educating personnel about the fund, and sponsorship of sales meetings, which may include covering costs of providing speakers, meals and other entertainment. The advisor may pay partnership and/or sponsorship fees to support seminars, conferences, and other programs designed to educate intermediaries about the fund and may cover the expenses associated with attendance at such meetings, including travel costs. The advisor and its affiliates may also pay fees related to obtaining data regarding intermediary or financial advisor activities to assist American Century with sales reporting, business intelligence and training and education opportunities. These payments and activities are intended to provide an incentive to intermediaries to sell the fund by educating them about the fund and helping defray the costs associated with offering the fund. These payments may create a conflict of interest by influencing the intermediary to recommend the fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information. The amount of any payments described in this paragraph is determined by the advisor or its affiliates, and all such amounts are paid out of their available assets, and not paid by you or the fund. As a result, the total expense ratio of the fund will not be affected by any such payments.
17


Financial Highlights 
Understanding the Financial Highlights 
The table on the next page itemizes what contributed to the changes in share price during the most recently ended fiscal year. It also shows the changes in share price for this period in comparison to changes over the last five fiscal years (or a shorter period if the fund is not five years old).
On a per-share basis, the table includes as appropriate 
share price at the beginning of the period
investment income and capital gains or losses
distributions of income and capital gains paid to investors
share price at the end of the period
The table also includes some key statistics for the period as appropriate 
Total Return – the overall percentage of return of the fund, assuming the reinvestment of all distributions
Expense Ratio – the operating expenses of the fund as a percentage of average net assets
Net Income Ratio – the net investment income of the fund as a percentage of average net assets
Portfolio Turnover – the percentage of the fund’s investment portfolio that is replaced during the period
The Financial Highlights have been audited by Deloitte & Touche LLP, independent registered public accounting firm. The Report of Independent Registered Public Accounting Firm and the financial statements are included in the fund’s annual report, which is available upon request.
18


American Century Diversified Municipal Bond ETF
For a Share Outstanding Throughout the Years Ended August 31 (except as noted)
Per-Share Data Ratios and Supplemental Data
    Income From Investment Operations: Ratio to Average Net Assets of:  
  Net
Asset Value, Beginning
of Period
Net
Investment
Income (Loss)(1)
Net
Realized and
Unrealized
Gain (Loss)
Total From
Investment
Operations
Distributions From Net Investment Income
Other Capital(1)
Net Asset Value, End of Period
Total
Return(2)
Operating
Expenses
Net
Investment
Income
(Loss)
Portfolio
Turnover
Rate(3)
Net Assets,
End of
Period
(in thousands)
2021 $53.61 1.00 1.83 2.83 (1.05) 0.09 $55.48 5.50% 0.29% 1.82% 14% $163,663 
2020 $53.37 1.19 0.11 1.30 (1.15) 0.09 $53.61 2.66% 0.29% 2.26% 23% $67,018 
2019(4)
$50.00 1.36 3.16 4.52 (1.25) 0.10 $53.37 9.42%
0.29%(5)
2.74%(5)
19% $26,684 
Notes to Financial Highlights
(1)Computed using average shares outstanding throughout the period.
(2)Total returns are calculated based on the net asset value of the last business day. Total returns for periods less than one year are not annualized.
(3)Excludes securities received or delivered in kind.
(4)September 10, 2018 (fund inception) through August 31, 2019.
(5)Annualized.
19


Notes



Notes



Notes



Where to Find More Information
Annual and Semiannual Reports
Additional information about the fund’s investments is available in the fund’s annual and semiannual reports to shareholders. In the fund’s annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the fund’s performance during its last fiscal year. This prospectus incorporates by reference the Report of Independent Registered Public Accounting Firm and the financial statements included in the fund’s annual report to shareholders dated August 31, 2021.
Statement of Additional Information (SAI)
The SAI contains a more detailed legal description of the fund’s operations, investment restrictions, policies and practices. The SAI is incorporated by reference into this prospectus. This means that it is legally part of this prospectus, even if you don’t request a copy.
You may obtain a free copy of the SAI, annual reports and semiannual reports, and you may ask questions about the fund or your accounts, online at americancenturyetfs.com, by contacting American Century Investments at the addresses or telephone numbers listed below or by contacting your financial intermediary.
The Securities and Exchange Commission (SEC)
Reports and other information about the fund are available on the EDGAR database on the SEC’s website at sec.gov, and copies of this information may be obtained, after paying a duplicating fee, by electronic request at the following email address: publicinfo@sec.gov.

This prospectus shall not constitute an offer to sell securities of the fund in any state, territory, or other jurisdiction where the fund’s shares have not been registered or qualified for sale, unless such registration or qualification is not required, or under any circumstances in which such offer or solicitation would be unlawful.



















American Century Investments
americancenturyetfs.com
Financial Professionals
P.O. Box 419385
Kansas City, Missouri 64141-6385
833-ACI-ETFS

Investment Company Act File No. 811-23305
CL-PRS-94305 2201