February 28, 2020
	(as revised December 2, 2020)

2020 Summary Prospectus

•  BlackRock Short Maturity Municipal Bond ETF | MEAR | CBOE BZX

Before you invest, you may want to review the Fund’s prospectus, which contains more information about the Fund and its risks. You can find the Fund’s prospectus (including amendments and supplements) and other information about the Fund, including the Fund’s statement of additional information and shareholder reports, online at https://www.ishares.com/prospectus. You can also get this information at no cost by calling 1-800-iShares (1-800-474-2737) or by sending an e-mail request to iSharesETFs@blackrock.com, or from your financial professional. The Fund’s prospectus and statement of additional information, both dated February 28, 2020, as amended and supplemented from time to time, are incorporated by reference into (legally made a part of) this Summary Prospectus. Information on the Fund’s net asset value, market price, premiums and discounts, and bid-ask spreads can be found at www.iShares.com.

Beginning on January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission (“SEC”), paper copies of the Fund’s shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports from your financial intermediary, such as a broker-dealer or bank. Instead, the reports will be made available on a website, and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. If you hold accounts through a financial intermediary, you may contact your financial intermediary to enroll in electronic delivery. Please note that not all financial intermediaries may offer this service.

You may elect to receive all future reports in paper free of charge. If you hold accounts through a financial intermediary, you can follow the instructions included with this disclosure, if applicable, or contact your financial intermediary to request that you continue to receive paper copies of your shareholder reports. Please note that not all financial intermediaries may offer this service. Your election to receive reports in paper will apply to all funds held with your financial intermediary.

The SEC has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

BLACKROCK^® SHORT MATURITY
MUNICIPAL BOND ETF

Ticker: MEAR Stock Exchange: Cboe BZX

Investment Objective

The BlackRock Short Maturity Municipal Bond ETF (the “Fund”) seeks to maximize tax-free current income.

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 iShares U.S. 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 the management fees, interest expenses, taxes, expenses incurred with respect to the acquisition and disposition of portfolio securities and the execution of portfolio transactions, including brokerage commissions, distribution fees or expenses, litigation expenses and extraordinary expenses.

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 (ongoing expenses that you pay each year as a percentage of the value of your investments)
Management Fees	Distribution and Service (12b-1) Fees	Other Expenses1	Total Annual Fund Operating Expenses
0.25%	None	0.00%	0.25%

¹ The amount rounded to 0.00%.

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. 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
$26	$80	$141	$318

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Portfolio Turnover. The Fund may pay 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 the 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 170% of the average value of its portfolio.

Principal Investment Strategies

The Fund seeks to achieve its investment objective by investing, under normal circumstances, at least 80% of its net assets in municipal securities such that the interest on each bond is exempt from U.S. federal income taxes and the federal alternative minimum tax (“AMT”). Under normal circumstances, the Fund primarily invests in U.S. dollar-denominated investment-grade short-term fixed- and floating-rate municipal securities with remaining maturities of five years or less, such as municipal bonds, municipal notes and variable rate demand obligations, as well as money market instruments and registered investment companies. Investment-grade securities are rated BBB- or higher by S&P Global Ratings and/or Fitch Ratings, Inc. (“Fitch”), or Baa3 or higher by Moody’s Investors Service, Inc. (“Moody's”), or, if unrated, determined by the Fund's management team to be of equivalent quality. Municipal bonds include debt obligations issued by or on behalf of a governmental entity or other qualifying issuer that pay interest that is, in the

opinion of bond counsel to the issuer at the time of issuance, generally excludable from gross income for U.S. federal income tax purposes. The Fund may invest up to 20% of its net assets in municipal securities that pay interest that is subject to the federal AMT. Issuers may be states, territories and possessions of the U.S., including the District of Columbia, and their political subdivisions, agencies and instrumentalities. BFA or its affiliates may advise the money market funds and investment companies in which the Fund may invest.

Under normal circumstances, the effective duration of the Fund's portfolio is expected to be 1.2 years or less, as calculated by the Fund's management team, and it is not expected to exceed 1.5 years. Effective duration is a measure of the Fund’s price sensitivity to changes in yields or interest rates; however, investors should be aware that effective duration is not an exact measurement and may not reliably predict a particular security’s price sensitivity to changes in yield or interest rates.

Under normal circumstances, the Fund will also seek to maintain a weighted average maturity that is less than three years. Weighted average maturity is a U.S. dollar-weighted average of the remaining term to maturity of the underlying securities in the Fund’s portfolio. For the purposes of determining the Fund’s weighted average maturity, a security’s final maturity date, or for amortizing securities such as asset-backed and mortgage-backed securities, its weighted average life, will be used for calculation purposes.

The Fund is an actively managed exchange-traded fund (“ETF”) that does

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not seek to replicate the performance of a specified index. The Fund may have a higher degree of portfolio turnover than funds that seek to replicate the performance of an index.

The Fund is not a money market fund and does not seek to maintain a stable net asset value of $1.00 per share. Please see the Fund’s Statement of Additional Information (“SAI”) for further information.

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 ETFs, the Fund is not an index-based ETF. The order of the below risk factors does not indicate the significance of any particular risk factor.

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

Authorized Participant Concentration Risk. Only an Authorized Participant (as defined in the Creations and Redemptions section of this prospectus (the “Prospectus”)) 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.

Call Risk. During periods of falling interest rates, an issuer of a callable bond held by the Fund may “call” or repay the security before its stated maturity, and the Fund may have to reinvest the proceeds in securities with lower yields, which would result in a decline in the Fund's income, or in securities with greater risks or with other less favorable features.

Cash Management Risk. If a significant amount of the Fund’s assets are invested in cash and cash equivalents, it will be more difficult for the Fund to achieve its investment objective. The Fund may underperform other funds that do not similarly invest in cash and cash equivalents for investment purposes and/or to collateralize derivative instruments.

Cash Transactions Risk. The Fund may effect part or all of its creations and redemptions for cash, rather than in-kind securities. As a result, the Fund may have to sell portfolio securities at inopportune times in order to obtain the cash needed to meet redemption orders. This may cause the Fund to sell a security and recognize a capital gain or loss that might not have been incurred if it had made a redemption in-kind. The use of cash creations and redemptions may also cause the Fund’s shares to trade in the market at wider

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bid-ask spreads or greater premiums or discounts to the Fund’s NAV.

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 or asset class.

Credit Risk. Debt issuers and other counterparties may be unable or unwilling to make timely interest and/or principal payments when due or otherwise honor their obligations. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also adversely affect the value of the Fund’s investment in that issuer. The degree of credit risk depends on an issuer's or counterparty's financial condition and on the terms of an obligation.

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

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

Floating Rate Notes Risk. Securities with floating or variable interest rates can be less sensitive to interest rate changes than securities with fixed interest rates, but may decline in value if their coupon rates do not reset as high, or as quickly, as comparable market interest rates, and generally carry lower yields than fixed notes of the same maturity. Although floating rate notes are less sensitive to interest rate risk than fixed-rate securities, they are subject to credit risk and default risk, which could impair their value.

High Portfolio Turnover Risk. The Fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover (considered by the Fund to mean higher than 100% annually) may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other securities.

Illiquid Investments Risk. The Fund may invest up to an aggregate amount of 15% of its net assets in illiquid investments. An illiquid investment is any investment that the Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without significantly changing the market value of the investment. To the extent the Fund holds illiquid investments, the illiquid investments may reduce the returns of the Fund because the Fund may be unable to transact at advantageous times or prices. During periods of market

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volatility, liquidity in the market for the Fund’s shares may be impacted by the liquidity in the market for the underlying securities or instruments held by the Fund, which could lead to the Fund’s shares trading at a premium or discount to the Fund’s NAV.

Income Risk. The Fund’s income may decline when interest rates fall because the Fund may hold a significant portion of short duration securities and/or securities that have floating or variable interest rates. The Fund’s income may decline because the Fund invests in lower yielding bonds, and as the bonds in its portfolio mature, are near maturity or are called, the Fund needs to purchase additional bonds.

Infectious Illness Risk. An outbreak of an infectious respiratory illness, COVID-19, caused by a novel coronavirus has resulted in travel restrictions, disruption of healthcare systems, prolonged quarantines, cancellations, supply chain disruptions, lower consumer demand, layoffs, ratings downgrades, defaults and other significant economic impacts. Certain markets have experienced temporary closures, extreme volatility, severe losses, reduced liquidity and increased trading costs. These events will have an impact on the Fund and its investments and could impact the Fund’s ability to purchase or sell securities or cause elevated tracking error and increased premiums or discounts to the Fund’s NAV. Other infectious illness outbreaks in the future may result in similar impacts.

Interest Rate Risk. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. Very low or negative interest rates may magnify interest rate

risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Fund may have a very low, or even negative yield. A low or negative yield would cause the Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments, including those held by the Fund. The historically low interest rate environment heightens the risks associated with rising interest rates.

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 in 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 risk analyses applied by BFA will not produce the desired results, and that securities selected by BFA may underperform the market or any relevant benchmark. In addition, legislative, regulatory, or tax developments may affect the

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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 issue, 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. 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 premiums or discounts to NAV. ANY OF THESE FACTORS, AMONG OTHERS, MAY LEAD TO THE FUND'S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV.

Municipal Securities Risk. Municipal securities can be significantly affected by political or economic changes, including changes made in the law after

issuance of the securities, as well as uncertainties in the municipal market related to taxation, legislative changes or the rights of municipal security holders, including in connection with an issuer insolvency. Municipal securities backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the inability to collect revenues from such projects or assets. Certain municipal securities are issued by entities with limited taxing authority such as school districts, or dependent on revenue from a particular sector or industry, such as the utilities sector, infrastructure sector, or transportation industry.

Not a Money Market Fund. The Fund is not a money market fund and is not subject to the strict rules that govern the quality, maturity, liquidity and other features of securities that money market funds may purchase. Under normal circumstances, the Fund’s investments may be more susceptible than a money market fund is to credit risk, interest rate risk, valuation risk and other risks relevant to the Fund’s investments. The Fund does not seek to maintain a stable net asset value of $1.00 per share.

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

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inadequate to address significant operational risks.

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.

Tax Risk. There is no guarantee that the Fund's income will be exempt from U.S. federal income taxes, the federal AMT or the federal Medicare contribution tax of 3.8% on “net investment income.”

Valuation Risk. The price the Fund could receive upon the sale of a security or other asset may differ from the Fund's valuation of the security or other asset, particularly for securities or other assets that trade in low volume or

volatile markets or that are valued using a fair value methodology as a result of trade suspensions or for other reasons. In addition, the value of the securities or other assets in the Fund's portfolio may change on days or during time periods when shareholders will not be able to purchase or sell the Fund's shares. Authorized Participants who purchase or redeem Fund shares on days when the Fund is holding fair-valued securities may receive fewer or more shares, or lower or higher redemption proceeds, than they would have received had the Fund not fair-valued securities or used a different valuation methodology. The Fund’s ability to value investments may be impacted by technological issues or errors by pricing services or other third-party service providers.

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Performance Information

The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Both assume that all dividends and distributions have been reinvested in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. If BFA had not waived certain Fund fees during certain periods, the Fund's returns would have been lower.

Year by Year Returns (Years Ended December 31)

The best calendar quarter return during the periods shown above was 0.60% in the 1st quarter of 2019; the worst was -0.17% in the 4th quarter of 2017.

Updated performance information, including the Fund’s current NAV, may be obtained by visiting our website at www.iShares.com or by calling 1-800-iShares (1-800-474-2737) (toll free).

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Average Annual Total Returns

(for the periods ended December 31, 2019)

	One Year	Since Fund Inception
(Inception Date: 3/3/2015)
Return Before Taxes	2.03%	1.14%
Return After Taxes on Distributions1	2.03%	1.14%
Return After Taxes on Distributions and Sale of Fund Shares1	1.85%	1.13%
Bloomberg Barclays Municipal Bond: 1 Year (1-2) Index2 (Index returns do not reflect deductions for fees, expenses, or taxes)	2.46%	1.20%

¹ After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to tax-exempt investors or investors who hold shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). Fund returns after taxes on distributions and sales of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sale of Fund shares. As a result, Fund returns after taxes on distributions and sales of Fund shares may exceed Fund returns before taxes and/or returns after taxes on distributions.

² The Bloomberg Barclays Municipal Bond: 1 Year (1-2) Index is an unmanaged index comprised of national municipal bond issues having a maturity of at least one year and less than two years.

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Management

Investment Adviser. BlackRock Fund Advisors.

Portfolio Managers. Scott Radell, Kristi Manidis and Kevin A. Schiatta (the “Portfolio Managers”) are primarily responsible for the day-to-day management of the Fund. Each Portfolio Manager supervises a portfolio management team. Mr. Radell has been a Portfolio Manager of the Fund since 2015. Ms. Manidis and Mr. Schiatta have been Portfolio Managers of the Fund since 2019.

Purchase and Sale of Fund Shares

The 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 primarily from net tax-exempt income (but not necessarily free from federal AMT), although distributions of taxable capital gains may also occur. The Fund is generally not an appropriate investment for a 401(k) plan or an IRA. Please consult your personal tax advisor.

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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For more information visit www.iShares.com or call 1-800-474-2737

IS-SP-MEAR-1220

Investment Company Act file No.: 811-22649