BLACKROCK FUTURE U.S. THEMES ETF

Ticker: BTHM

Stock Exchange: NYSE Arca

Investment Objective

The BlackRock Future U.S. Themes ETF (the “Fund”) seeks long-term capital appreciation.

Fees and Expenses

The following table describes the fees and expenses that you will incur if you buy, hold and sell shares of the Fund. The investment advisory agreement between BlackRock ETF Trust (the “Trust”) and BlackRock Fund Advisors (“BFA”) (the “Investment Advisory Agreement”) provides that BFA will pay all operating expenses of the Fund, except: (i) the management fees, (ii) interest expenses, (iii) taxes, (iv) expenses incurred with respect to the acquisition and disposition of portfolio securities and the execution of portfolio transactions, including brokerage commissions, (v) distribution fees or expenses, and (vi) litigation expenses and any extraordinary expenses. The Fund may incur “Acquired Fund Fees and Expenses.” Acquired Fund Fees and Expenses reflect the Fund's pro rata share of the fees and expenses incurred indirectly by the Fund as a result of investing in other investment companies. The impact of Acquired Fund Fees and Expenses is included in the total returns of the Fund.

You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Annual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investments)
Management Fees1		Distribution and Service (12b-1) Fees		Other Expenses		Total Annual Fund Operating Expenses		Fee Waiver1		Total Annual Fund Operating Expenses After Fee Waiver1
0.60%		None		None		0.60%		—		0.60%

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As described in the “Management” section of the Fund's prospectus beginning on page 15, BFA has contractually agreed to waive a portion of its management fees in an amount equal to the aggregate Acquired Fund Fees and Expenses, if any, attributable to investments by the Fund in other funds advised by BFA or its affiliates through June 30, 2024. The agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

Example. This Example is intended to help you compare the cost of owning shares of the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.

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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
	$61		$192		$335		$750

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sell exchange-listed and over-the-counter (“OTC”) put and call options on securities and swap contracts, financial indices and futures contracts and use other derivative instruments or management techniques (collectively, “Strategic Transactions”). The Fund may engage in Strategic Transactions for duration management and other risk management purposes, including to attempt to protect against possible changes in the market value of the Fund’s portfolio resulting from trends in the securities markets and changes in interest rates or to protect the Fund’s unrealized gains in the value of its portfolio securities, to facilitate the sale of portfolio securities for investment purposes, to establish a position in the securities markets as a temporary substitute for purchasing particular securities or to enhance income or gain.

The Fund may lend securities representing up to one-third of the value of the Fund's total assets (including the value of the collateral received).

Summary of Principal Risks

As with any investment, you could lose all or part of your investment in the Fund, and the Fund's performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund's net asset value per share (“NAV”), trading price, yield, total return and ability to meet its investment objective. Unlike many exchange-traded funds (“ETFs”), the Fund is not an index-based ETF. The relative significance of each risk factor below may change over time and you should review each risk factor carefully.

Equity Securities Risk. Equity securities are subject to changes in

value, and their values may be more volatile than those of other asset classes. Common stocks generally subject their holders to more risks than preferred stocks and debt securities because common stockholders’ claims are subordinated to those of holders of preferred stocks and debt securities upon the bankruptcy of the issuer.

Growth Securities Risk. The Fund invests in growth securities, which may be more volatile than other types of investments, may perform differently than the market as a whole and may underperform when compared to securities with different investment parameters. Companies with forecasted higher levels of sales growth relative to U.S. domestic capital spending may not in fact experience growth or higher growth relative to U.S. capital expenditures. Under certain market conditions, growth securities have performed better during the later stages of economic recovery (although there is no guarantee that they will continue to do so). Therefore, growth securities may go in and out of favor over time.

Risk of Investing in the U.S. Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.

Asset Class Risk. Securities and other assets or financial instruments in the Fund's portfolio may underperform in comparison to the general financial markets, a particular financial market or other asset classes.

Assets Under Management (AUM) Risk. From time to time, an Authorized Participant (as defined in the Creations and Redemptions section of the Prospectus), a third-party investor, the

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Fund’s adviser or an affiliate of the Fund’s adviser, or a fund may invest in the Fund and hold its investment for a specific period of time in order to facilitate commencement of the Fund’s operations or to allow the Fund to achieve size or scale. There can be no assurance that any such entity would not redeem its investment or that the size of the Fund would be maintained at such levels, which could negatively impact the Fund.

Authorized Participant Concentration Risk. Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund, and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. The Fund has a limited number of institutions that may act as Authorized Participants on an agency basis (i.e., on behalf of other market participants). To the extent that Authorized Participants exit the business or are unable to proceed with creation or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem, Fund shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting. Authorized Participant concentration risk may be heightened for ETFs, such as the Fund, that invest in securities issued by non-U.S. issuers or other securities or instruments that have lower trading volumes.

Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund's investments are concentrated in the securities and/or other assets of a particular issuer or

issuers, country, group of countries, region, market, industry, group of industries, sector, market segment or asset class.

Convertible Securities Risk. The market price of a convertible security generally tends to behave like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Because a convertible security derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.

Cybersecurity Risk. Failures or breaches of the electronic systems of the Fund, the Fund's adviser, distributor, and other service providers (including the benchmark provider), market makers, Authorized Participants or the issuers of securities in which the Fund invests have the ability to cause disruptions, negatively impact the Fund’s business operations and/or potentially result in financial losses to the Fund and its shareholders. While the Fund has established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Furthermore, the Fund cannot control the cybersecurity plans and systems of

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the Fund’s service providers, market makers, Authorized Participants or issuers of securities in which the Fund invests.

Depositary Receipts Risk. The Fund will invest in stocks of foreign corporations. The Fund’s investment in such stocks will be in the form of depositary receipts including American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”). While the use of ADRs and GDRs, which are traded on exchanges and represent an ownership in a foreign security, provide an alternative to directly purchasing the underlying foreign securities in their respective markets and currencies, investments in ADRs and GDRs continue to be subject to many of the risks associated with investing directly in foreign securities, including political, economic, and currency risk.

Derivatives Risk. The Fund may invest in certain types of derivatives contracts, including futures, options and swaps, which can be more sensitive to changes in interest rates or to sudden fluctuations in market prices than conventional securities, which can result in greater losses to the Fund.

Forward Foreign Currency Exchange Contracts. Forward foreign currency exchange transactions are OTC contracts to purchase or sell a specified amount of a specified currency or multinational currency unit at a price and future date set at the time of the contract. Forward foreign currency exchange contracts do not eliminate fluctuations in the value of non-U.S. securities but rather allow the Fund to establish a fixed rate of exchange for a future point in time. This strategy can

have the effect of reducing returns and minimizing opportunities for gain.

Futures Contract Risk. Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. Unlike equities, which typically entitle the holder to a continuing ownership stake in an issuer, futures contracts normally specify a certain date for settlement in cash based on the level of the reference rate. The primary risks associated with the use of futures contracts, or swaps or other derivatives referencing futures contracts, are: (i) the imperfect correlation between the change in market value of the instruments or swaps or other derivatives referencing futures contracts held by the Fund and the price of the futures contract; (ii) possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (iii) losses caused by unanticipated market movements, which are potentially unlimited; (iv) BFA’s inability to predict correctly the direction of prices and other economic factors; and (v) the possibility that the counterparty will default in the performance of its obligations.

Infectious Illness Risk. A widespread outbreak of an infectious illness, such as the COVID-19 pandemic, may result in travel restrictions, disruption of healthcare services, prolonged quarantines, cancellations, supply chain disruptions, business closures, lower consumer demand, layoffs, ratings downgrades, defaults and other significant economic, social and political impacts. Markets may experience

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temporary closures, extreme volatility, severe losses, reduced liquidity and increased trading costs. Such events may adversely affect the Fund and its investments and may impact the Fund's ability to purchase or sell securities or cause increased premiums or discounts to the Fund's NAV. Despite the development of vaccines, the duration of the COVID-19 pandemic and its effects cannot be predicted with certainty.

Issuer Risk. The performance of the Fund depends on the performance of individual securities to which the Fund has exposure. The Fund may be adversely affected if an issuer of underlying securities held by the Fund is unable or unwilling to repay principal or interest when due. Changes to the financial condition or credit rating of an issuer of those securities may cause the value of the securities to decline.

Management Risk. The Fund is subject to management risk, which is the risk that the investment process, techniques and analyses applied by BFA will not produce the desired results, and those securities or other financial instruments selected by BFA may result in returns that are inconsistent with the Fund’s investment objective. In addition, legislative, regulatory, or tax developments may affect the investment techniques available to BFA in connection with managing the Fund and may also adversely affect the ability of the Fund to achieve its investment objective.

Market Risk. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns. Local, regional or global events such as war, acts of

terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments and could result in increased premiums or discounts to the Fund's NAV.

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 disruptions in the creation/redemption process. Unlike some ETFs that track specific indexes, the Fund does not seek to replicate the performance of a specified index. Index-based ETFs have generally traded at prices that closely correspond to NAV per share. Given the high level of transparency of the Fund's holdings, BFA believes that the trading experience of the Fund should be similar to that of index-based ETFs. However, ETFs that do not seek to replicate the performance of a specified index have a limited trading history and, therefore, there can be no assurance as to whether, and/or the extent to which, the Fund's shares will trade at a premium or discount to NAV. ANY OF THESE FACTORS, AMONG OTHERS, MAY LEAD TO THE FUND'S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV.

“New Issues” Risk. “New issues” are IPOs of equity securities. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO.

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Non-Diversification Risk. The Fund is classified as non-diversified. This means that, compared with other funds that are classified as “diversified,” the Fund may invest a greater percentage of its assets in securities issued by or representing a small number of issuers. As a result, the Fund's performance may depend on the performance of a small number of issuers.

Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The Fund and BFA seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address significant operational risks.

Options. An option is an agreement that, for a premium payment or fee, gives the option holder (the purchaser) the right but not the obligation to buy (a “call option”) or sell (a “put option”) the underlying asset (or settle for cash in an amount based on an underlying asset, rate, or index) at a specified price (the “exercise price”) during a period of time or on a specified date. Investments in options are considered speculative. When the Fund purchases an option, it may lose the total premium paid for it if the price of the underlying security or other assets decreased, remained the same or failed to increase to a level at or beyond the exercise price (in the case of a call option) or increased, remained the same or failed to decrease to a level at or below the exercise price (in the case of a put option). If a put or

call option purchased by the Fund were permitted to expire without being sold or exercised, its premium would represent a loss to the Fund. To the extent that the Fund writes or sells an option, if the decline or increase in the underlying asset is significantly below or above the exercise price of the written option, the Fund could experience a substantial loss.

Preferred Stock Risk. Preferred stocks are subject not only to issuer-specific and market risks generally applicable to equity securities, but also risks associated with fixed-income securities, such as interest rate risk. A company’s preferred stock, which may pay fixed or variable rates of return, generally pays dividends only after the company makes required payments to creditors, including vendors, depositors, counterparties, holders of its bonds and other fixed-income securities. As a result, the value of a company’s preferred stock will react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. Preferred stock may be less liquid than many other types of securities, such as common stock, and generally has limited or no voting rights. Preferred stock generally does not reflect the performance of a company as directly as the company’s common stock. In addition, preferred stock is subject to the risks that a company may defer or not pay dividends, and, in certain situations, may call or redeem its preferred stock or convert it to common stock. An issuer may decide to call its outstanding preferred stock in various environments based on its assessment of the relative cost of capital across the company’s capital structure. A market-wide increase in preferred stock being

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called may reduce the aggregate size of the preferred stock universe and the number of issuers with preferred stock outstanding. To the extent that the Fund invests a substantial portion of its assets in convertible preferred stocks, declining common stock values may also cause the value of the Fund’s investments to decline.

Risk of Swap Agreements. Swaps can involve greater risks than direct investment in securities because swaps may be leveraged and are subject to counterparty risk (e.g., the risk of a counterparty defaulting on the obligation or bankruptcy), credit risk and pricing risk (i.e., swaps may be difficult to value). Swaps may be subject to illiquidity risk, and it may not be possible for the Fund to liquidate a swap position at an advantageous time or price, which may result in significant losses. and centrally cleared. Most other swaps are entered into on a negotiated, bi-lateral basis and traded in the OTC market. Swaps are subject to bi-lateral variation margin. Initial margin requirements are in the process of being phased in, and the Fund may be subject to such requirements as early as September 2022. These requirements may raise the costs for the Fund’s investment in swaps. Central clearing is expected to reduce counterparty credit risk and increase liquidity, but central clearing does not make swap transactions risk-free. All swaps require posting of collateral which may restrict the ability of the Fund to invest the assets in different ways and which involve costs to the Fund. Swaps provide customized contractual terms, which may not, in all cases, provide the hedging or other intended benefits.

Securities Lending Risk. The Fund may engage in securities lending. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money if it does not recover the securities and/or the value of the collateral falls, including the value of investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund.

Small Fund Risk. When the Fund’s size is small, the Fund may experience low trading volume and wide bid/ask spreads. In addition, the Fund may face the risk of being delisted if the Fund does not meet certain conditions of the listing exchange. Any resulting liquidation of the Fund could cause the Fund to incur elevated transaction costs for the Fund and negative tax consequences for its shareholders.

Value Securities Risk. Securities issued by companies that may be perceived as undervalued may fail to appreciate for long periods of time and may never realize their full potential value. Value securities have generally performed better than non-value securities during periods of economic recovery (although there is no assurance that they will continue to do so). Value securities may go in and out of favor over time.

Warrants Risk. If the price of the underlying stock does not rise above the exercise price before the warrant expires, the warrant generally expires without any value and the Fund will lose any amount it paid for the warrant. Thus, investments in warrants may involve substantially more risk than investments in common stock. Warrants

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may trade in the same markets as their underlying stock; however, the price of the warrant does not necessarily move with the price of the underlying stock.

Performance Information

As of the date of this Prospectus, the Fund does not have a full calendar year of performance information to report.

Management

Investment Adviser. The Fund’s investment adviser is BFA.

Portfolio Managers. Raffaele Savi, Travis Cooke, CFA, Linus Franngard, and Philip Hodges, PhD, (the “Portfolio Managers”) are jointly and primarily responsible for the day-to-day management of the Fund. Raffaele Savi, Travis Cooke, CFA, Linus Franngard, and Philip Hodges, PhD, have been Portfolio Managers of the Fund since December 2021.

Purchase and Sale of Fund Shares

This Fund is an ETF. Individual shares of the Fund may only be bought and sold in the secondary market through a broker-dealer. Because ETF shares trade at market prices rather than at 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 (the “bid-ask spread”).

Tax Information

The Fund intends to make distributions that may be taxable to you as ordinary income or capital gains, unless you are investing through a tax-deferred arrangement such as a 401(k) plan or an individual retirement account (“IRA”), in which case, your distributions generally will be taxed when withdrawn.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), BFA or other related companies may pay the intermediary for marketing activities and presentations, educational training programs, conferences, the development of technology platforms and reporting systems or other services related to the sale or promotion of the Fund. 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.

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Investment Company Act File No.: 811-23402