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.

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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Portfolio Turnover

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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. Because the fund is new, the fund’s portfolio turnover rate is not available.

Expense Exchange Traded Fund Commissions [Text]

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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.

Other Expenses, New Fund, Based on Estimates [Text]

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Other expenses are based on estimated amounts for the current fiscal year.

Expense Example [Heading]

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Example

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The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other funds.

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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:

Strategy [Heading]

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Principal Investment Strategies

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The fund will generally invest in large capitalization companies it believes show sustainable business improvement using a proprietary multi-factor model that combines fundamental measures of a stock’s value and growth potential with environmental, social, and governance (ESG) metrics. The model assigns each security a financial metrics score and an ESG score that are combined to create an overall score.

To measure value, the portfolio managers may use ratios of stock price-to-earnings and stock price-to-cash flow. To measure growth, the managers may use the rate of growth of a company’s earnings and cash flow and changes in its earnings estimates. The model also considers price momentum. The team arrives at an ESG score by evaluating multiple metrics of each ESG characteristic—environmental, social, and governance. The portfolio managers utilize internal data and research, as well as third party commercial data sources and scoring systems, to evaluate each security’s ESG characteristics. For example, portfolio managers will consider, among others, a company’s carbon emission profile (environmental), a company’s employee turnover rates and digital privacy (social), and a company’s corporate leadership, including board chair independence and the independence of audit and compensation committees (governance). If information on a specific metric is unavailable, the security may still be selected for the portfolio if the portfolio managers believe they can evaluate the security qualitatively, or if the financial metrics and remaining ESG scores merit investment.

Final scores for each security are evaluated on a sector-specific basis, and the fund seeks to hold securities with the strongest scores in their respective sectors. Using this process, the portfolio managers attempt to build a portfolio of stocks that has sustainable competitive advantages, provides better returns without taking on significant additional risk, and maintains a stronger ESG profile than the S&P 500^® Index.

Under normal market conditions, the fund will invest at least 80% of its assets in sustainable equity securities. For this purpose, the advisor defines sustainable securities as those to which the advisor’s proprietary model assigns an ESG score that is in the top three quartiles of the ESG scores the model assigns to all of the securities in the fund’s benchmark, the S&P 500^® Index. The fund will invest principally in exchange-traded common stocks. The fund defines large capitalization companies as companies with capitalizations in the capitalization range of the S&P 500^® Index.

When determining whether to sell a security, the portfolio managers consider among other things, a security’s price, whether a security’s risk parameters outweigh its return opportunities, general market conditions, and whether the security meets their ESG criteria.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) or the Bloomberg Industry Classification Standard (BICS) for the tobacco industry.

The fund is an actively managed, nontransparent exchange-traded fund (ETF) that does not seek to replicate the performance of a specified index. In lieu of publishing its portfolio contents (Actual Portfolio) daily, the fund publishes a proxy portfolio (Proxy Portfolio) each day and on its website. There is no minimum overlap required between the Actual Portfolio and the Proxy Portfolio.

Risk [Heading]

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Principal Risks

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Proxy Portfolio Risk - The goal of the Proxy Portfolio is, during all market conditions, to track closely the daily performance of the Actual Portfolio and minimize intra-day misalignment between the performance of the Proxy Portfolio and the performance of the Actual Portfolio. The Proxy Portfolio is designed to reflect the economic exposures and the risk characteristics of the Actual Portfolio on any given trading day.

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The Proxy Portfolio methodology is novel and not yet proven as an effective arbitrage mechanism. The effectiveness of the Proxy Portfolio as an arbitrage mechanism is contingent upon, among other things, the fund’s factor model analysis creating a proxy portfolio that performs in a manner substantially identical to the performance of the fund’s actual portfolio. While the Proxy Portfolio may include some of the fund’s holdings, it is not the fund’s Actual Portfolio. ETFs trading on the basis of a published Proxy Portfolio may exhibit wider premiums and discounts, bid/ask spreads, and tracking error than other ETFs using the same investment strategies that publish their portfolios on a daily basis, especially during periods of market disruption or volatility. Therefore, shares of the fund may cost investors more to trade than shares of a traditional ETF.

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Each day the fund calculates the overlap between the holdings of the prior Business Day’s Proxy Portfolio compared to the Actual Portfolio (Proxy Overlap) and the difference, in percentage terms, between the Proxy Portfolio per share NAV and that of the Actual Portfolio (Tracking Error). If the Tracking Error becomes large, there is a risk that the performance of the Proxy Portfolio may deviate from the performance of the Actual Portfolio.


◦	The fund’s Board of Trustees monitors its Tracking Error and bid/spread. If deviations become too large, the Board will consider the continuing viability of the fund, whether shareholders are being harmed, and what, if any, corrective measures would be appropriate. See the Statement of Additional Information for further discussion of the Board’s monitoring responsibilities.


◦	Although the fund seeks to benefit from keeping its portfolio information secret, market participants may attempt to use the Proxy Portfolio to identify a fund’s trading strategy, which if successful, could result in such market participants engaging in certain predatory trading practices that may have the potential to harm the fund and its shareholders.

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Premium/Discount Risk - Publication of the Proxy Portfolio is not the same level of transparency as the publication of the full portfolio by a fully transparent active ETF. Although the Proxy Portfolio is intended to provide investors with enough information to allow for an effective arbitrage mechanism that will keep the market price of the fund at or close to the underlying net asset value (NAV) per share of the fund, there is a risk (which may increase during periods of market disruption or volatility) that market prices will vary significantly from the underlying NAV of the fund. This means the price paid to buy shares on an exchange may not match the value of the fund’s portfolio. The same is true when shares are sold.

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Trading Issues Risk - If securities representing 10% or more of the fund’s Actual Portfolio do not have readily available market quotations, the fund will promptly request that the Exchange halt trading in the fund’s shares. Trading halts may have a greater impact on this fund compared to other ETFs due to the fund’s nontransparent structure. If the trading of a security held in the fund’s Actual Portfolio is halted, or otherwise does not have readily available market quotations, and the Advisor believes that the lack of any such readily available market quotations may affect the reliability of the Proxy Portfolio as an arbitrage vehicle, or otherwise determines it is in the best interest of the fund, the Advisor promptly will disclose on the fund’s website the identity and weighting of such security for so long as such security’s trading is halted or otherwise does not have readily available market quotations and remains in the Actual Portfolio.

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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. The fact that the fund is offering a novel and unique structure may affect the number of entities willing to act as Authorized Participants. During times of market stress, Authorized Participants may be more likely to step away from this type of ETF than a traditional ETF.

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ESG Criteria Risk - Because the fund’s ESG criteria may exclude the securities of certain issuers for nonfinancial reasons, the fund may forgo some market opportunities available to funds that do not use ESG criteria. ESG considerations maybe linked to long term rather than short term returns. Furthermore, when analyzing ESG criteria for securities, the portfolio management team relies on the information and scoring models published by third party sources, there is a risk that this information might be incorrect or only take into account one of many ESG related components of portfolio companies. Moreover, scores and ratings across third party providers may be inconsistent or incomparable.


•	Style Risk - If at any time the market is not favoring the fund’s investment process, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

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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.

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Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market. 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.

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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.

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.

Risk Lose Money [Text]

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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.

Risk Not Insured Depository Institution [Text]

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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.

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Fund Performance

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The fund’s performance history is not available as of the date of this prospectus. When the fund has investment results for a full calendar year, this section will feature charts that show annual total returns, highest and lowest quarterly returns and average annual total returns for the fund. This information indicates the volatility of the fund’s historical returns from year to year. For current performance information, please visit americancenturyetfs.com.

Performance information is designed to help you see how fund returns can vary. Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

Performance Information Illustrates Variability of Returns [Text]

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This information indicates the volatility of the fund’s historical returns from year to year.

Performance One Year or Less [Text]

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Performance Availability Website Address [Text]

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americancenturyetfs.com

Performance Past Does Not Indicate Future [Text]

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Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

American Century ETF Trust | American Century Sustainable Equity ETF | American Century Sustainable Equity ETF