April 5, 2018

2018 Summary Prospectus

^► iShares Bloomberg Roll Select Commodity Strategy ETF | CMDY |  NYSE ARCA

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 report, online at http://us.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 21, 2018, as amended and supplemented from time to time, are incorporated by reference into (legally made a part of) this Summary Prospectus.

The Securities and Exchange Commission (“SEC”) and Commodity Futures Trading Commission (“CFTC”) have not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

iSHARES^® BLOOMBERG ROLL SELECT COMMODITY STRATEGY ETF

Ticker: CMDY Stock Exchange: NYSE Arca

Investment Objective

The iShares Bloomberg Roll Select Commodity Strategy ETF (the “Fund”) seeks to provide exposure, on a total return basis, to a diversified group of commodities.

Fees and Expenses

The following table describes the fees and expenses that you will incur if you own 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, commodities or other financial instruments and the execution of portfolio transactions, including brokerage commissions, distribution fees or expenses, litigation expenses and any extraordinary expenses.

You may also incur usual and customary brokerage commissions and other charges when buying or selling shares of the Fund, which are not reflected in the Example that follows:

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 Expenses	Total Annual Fund Operating Expenses
0.28%	None	None	0.28%

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
$29	$90

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Portfolio Turnover. The Fund may pay transaction costs, such as commissions, when it buys and sells securities or other assets (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.

Principal Investment Strategies

The Fund seeks to achieve its investment objective by investing in exchange-traded futures contracts on the Bloomberg Roll Select Commodity Index (the “Index Futures”). The Fund is expected to roll out of existing positions in Index Futures and establish new positions in Index Futures on an ongoing basis. Index Futures subsequently acquired by the Fund may have terms that differ from those of the Index Futures it currently holds and the purchase and sale of these Index Futures may incur transaction fees. In seeking total return, the Fund also seeks to generate interest income and capital appreciation on the cash balances arising from its investment in Index Futures through a cash management strategy consisting of investments in cash and cash equivalents, short-term government obligations and short-term investment-grade fixed-income securities (collectively, “Fixed-Income Investments”).

The Fund is an actively managed exchange-traded fund (“ETF”) and does not seek to replicate the performance of a specified index. While the Fund is not an index fund, the Fund’s

investment strategy seeks to maximize correlation with the Bloomberg Roll Select Commodity Index (the “Bloomberg Benchmark”), which is composed of 22 futures contracts across 20 physical agricultural, energy, precious metals and industrial metals commodities. The Bloomberg Benchmark reflects the returns from these commodity futures contracts, and provides broad-based exposure to commodities as an asset class by using liquidity factors and sector caps to avoid over-concentration in any single commodity or commodity sector. The Fund will invest in financial instruments providing exposure to commodities and not in the physical commodities themselves. The Bloomberg Benchmark employs a contract roll strategy intended to minimize the effects of contango and maximize the effects of backwardation. Contango refers to a situation in which the futures price of a commodity is above the spot price. Backwardation is the opposite of contango and refers to a situation in which the spot price of a commodity is above the futures price.

The Fund may also invest in exchange-traded commodity futures contracts similar to those found in the Bloomberg Benchmark, as well as swaps and options on futures that correlate to the investment returns of commodities without investing directly in physical commodities and over-the counter commodity-linked instruments like commodity-linked notes, swaps and forward contracts (together, the “Commodity Investments”). Investing in derivative contracts may have a leveraging effect on the Fund. Although the Fund may hold the same futures contracts under the same futures rolling schedule as those included in the

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Bloomberg Benchmark, the Fund is not obligated to invest in any futures contracts included in, and does not seek to replicate the performance of, the Bloomberg Benchmark.

The Fund seeks to gain exposure to Index Futures and other Commodity Investments by investing through a wholly-owned subsidiary organized in the Cayman Islands (the “Subsidiary”). The Subsidiary is advised by BFA and has the same investment objective as the Fund. Unlike the Fund, the Subsidiary is not an investment company registered under the Investment Company Act of 1940, as amended (the “1940 Act”). The Subsidiary invests solely in Commodity Investments and cash and cash equivalents.

The Fund will not invest more than 25% of its total assets in the Subsidiary. The Fund’s Commodity Investments held in the Subsidiary are intended to provide the Fund with exposure to broad commodities consistent with current U.S. federal income tax laws applicable to investment companies such as the Fund, which limit the ability of investment companies to invest directly in Commodity Investments.

The remainder of the Fund's assets will be invested directly by the Fund and will primarily be invested in Fixed-Income Investments including repurchase agreements, money market instruments, U.S. government and agency securities, treasury inflation-protected securities, sovereign debt obligations on non-U.S. countries and investment-grade corporate bonds. The Fund invests in the Fixed-Income Investments for investment purposes and to collateralize the Subsidiary's derivatives exposure on a day-to-day basis.

The Commodity Futures Trading Commission (“CFTC”) has adopted certain requirements that subject registered investment companies and their advisers to regulation by the CFTC if a registered investment company invests more than a prescribed level of its net asset value in CFTC-regulated futures, options and swaps, or if a registered investment company markets itself as providing investment exposure to such instruments. Due to the Fund’s potential use of CFTC-regulated futures, options and swaps above the prescribed levels, it is considered a “commodity pool” under the Commodity Exchange Act (“CEA”).

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 actively managed and is not an index-based ETF.

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 (including the futures market).

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

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in order to facilitate commencement of the Fund’s operations or to allow the Fund to achieve size or scale. Therecan 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. 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 Creation Units (as defined in the Purchase and Sale of Fund Shares section of the Prospectus), Fund shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting.

Cash Management Risk. If a significant amount of the Fund’s assets are invested in cash and cash equivalents, 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.

Commodity-Linked Derivatives Risk. The Fund will invest in certain commodity-linked derivative instruments, including futures, options on futures and swaps. The value of a commodity-linked derivative instrument typically is based upon the price movements of the underlying commodity or an economic variable

linked to such price movements. The prices of commodity-related investments may fluctuate quickly and dramatically as a result of changes affecting a particular commodity and may not correlate to price movements in other asset classes, such as stocks, bonds and cash. Commodity-linked derivatives are subject to the risk that the counterparty to the transaction, the exchange or trading facility on which they trade or the applicable clearing house may default or otherwise fail to perform. In addition, each exchange or trading facility on which the derivatives are traded has the right to suspend or limit trading in all futures or other instruments that it lists. The Fund’s use of commodity-linked derivatives may also have a leveraging effect on the Fund’s portfolio. Leverage generally magnifies the effect of a change in the value of an asset and creates a risk of loss of value on a larger pool of assets than the Fund would otherwise have had. The Fund is required to post margin in respect to its holdings in derivatives. Each of these factors and events could have a significant negative impact on the Fund.

Commodity Regulatory Risk. The Fund and the Subsidiary are deemed commodity pools and BFA is considered a “commodity pool operator” with respect to the Fund under the CEA. BFA is therefore subject to regulation by the SEC and the CFTC. The regulatory requirements governing the use of commodity futures, options on commodity futures, certain swaps or certain other investments could change at any time.

Commodity Risk. The Fund has substantial exposure to commodities. The Fund invests in instruments and companies that are susceptible to

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fluctuations in certain commodity markets. Any negative changes in commodity markets that may be due to changes in supply and demand for commodities, market events, regulatory developments or other factors that the Fund cannot control could have an adverse impact on those companies.

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 of a particular issuer or issuers, country, group of countries, region, market, industry, group of industries, sector or asset class.

Counterparty Risk. Certain commodity-linked derivative instruments, swap agreements and other forms of financial instruments that involve counterparties subject the Fund to the risk that the counterparty could default on its obligations under the agreement, either through the counterparty’s bankruptcy or failure to perform its obligations. In the event of a counterparty default, the Fund could experience lengthy delays in recovering some or all of its assets or obtain no recovery at all. The Fund’s investments in the futures markets also introduce the risk that its futures commission merchant (“FCM”) could default on an obligation set forth in an agreement between the Fund and the FCM, including the FCM’s obligation to return margin posted in connection with the Fund’s futures contracts.

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.

Cyber Security Risk. Failures or breaches of the electronic systems of the Fund, the Fund's adviser, distributor, and other service providers, market makers, Authorized Participants or the issuers of securities in which the Fund invests have the ability to cause disruptions and negatively impact the Fund’s business operations, potentially resulting 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 cyber security plans and systems of the Fund’s service providers, market makers, Authorized Participants or issuers of securities in which the Fund invests.

Derivatives Risk. The Fund’s use of derivatives may reduce the Fund’s returns or increase volatility. Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. Derivatives may also be subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation. A risk of the Fund’s use of derivatives is that the fluctuations in their values may not correlate perfectly with the value of the underlying asset, the performance of the asset class to which the Fund seeks exposure or the

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performance of the overall markets. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, or movements between the time of periodic reallocations of Fund assets, which losses are potentially unlimited. Certain derivatives may give rise to a form of leverage and may expose the Fund to greater risk and increase its costs. The impact of increasing U.S. and global regulation of derivatives may make derivatives more costly, may limit the availability of derivatives, may delay or restrict the exercise by the Fund of termination rights or remedies upon a counterparty default under derivatives held by the Fund (which could result in losses), or may otherwise adversely affect the value or performance of derivatives.

Energy Sector Risk. The market value of securities in the energy sector may decline for many reasons, including, among others, changes in energy prices, energy supply and demand, government regulations and energy conservation efforts.

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 a corporation, 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 are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract; (b) possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) BFA’s inability to predict correctly the direction of prices and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.

Income Risk. The Fund's income may decline when yields fall. This decline can occur because the Fund may subsequently invest in lower-yielding bonds as bonds in its portfolio mature, are near maturity or are called, bonds are substituted, or the Fund otherwise needs to purchase additional bonds.

Interest Rate Risk. An increase in interest rates may 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. The historically low interest rate environment, together with recent modest rate increases, increases the risks associated with rising interest rates.

Issuer Risk. The performance of the Fund depends on the performance of individual securities or other assets to which the Fund has exposure. Changes in the financial condition or credit rating of an issuer of those securities or assets

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may cause the value of the securities or assets to decline.

Liquidity Risk. Liquidity risk exists when particular investments are difficult to purchase or sell. This can reduce the Fund's returns because the Fund may be unable to transact at advantageous times or prices.

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 or assets selected by BFA may underperform the market or any relevant benchmark. 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.

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.

Money Market Instruments Risk. The value of money market instruments may be affected by changing interest rates and by changes in the credit ratings of the investments. If a significant amount of the Fund's assets are invested in money market instruments, it will be more difficult for the Fund to achieve its investment objective. An investment in a money market fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. It is possible to lose money by investing in a money market fund. Money market funds other than government money market funds or retail money market funds “float” their NAV instead of using a stable $1.00 per share price.

Non-Diversification Risk. The Fund may invest a large 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

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inadequate to address significant operational risks.

Risk of Investing in Agriculture and Livestock. Investments in the agricultural and livestock sectors may be volatile and change unpredictably as a result of many factors, such as legislative or regulatory developments relating to food safety, the imposition of tariffs or other trade restraints, and the supply and demand of each commodity. Increased competition and changes in consumer tastes and spending can also influence the demand for agricultural and livestock products, affecting the price of such commodities and the performance of the Fund.

Risk of Investing in Industrial Metals. The industrial metals sector may be adversely affected by changes in international economic and political conditions, increased competition and changes in industrial and commercial demand for industrial metals. As a result, the price of industrial metals has been subject to substantial price fluctuations over short periods of time.

Risk of Investing in the United States. 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.

Risk of Swap Agreements. A swap is a two-party contract that generally obligates each counterparty to exchange periodic payments based on a pre-determined underlying investment or notional amount and to exchange collateral to secure the obligations of each counterparty. Swaps may be leveraged and are subject to counterparty risk, credit risk and pricing risk. Swaps may also be considered

illiquid. 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.

Subsidiary Risk. The Fund may invest up to 25% of its total assets in the Subsidiary. By investing in the Subsidiary, the Fund is indirectly exposed to the risks associated with the Subsidiary’s investments. The Subsidiary is not registered under the 1940 Act, and, unless otherwise noted in this prospectus, is not subject to the investor protections of the 1940 Act. Changes in the laws of the U.S. and/or the Cayman Islands could result in the inability of the Fund and/or the Subsidiary to operate as described in the Prospectus and the Statement of Additional Information (“SAI”), and could adversely affect the Fund.

Tax Risk. The Fund invests in commodity-linked derivatives indirectly through the Subsidiary because income from these investments, if made directly, might not be treated as “qualifying income” for purposes of the Fund qualifying as a regulated investment company (“RIC”) for U.S. federal income tax purposes. The Fund expects its income with respect to the Subsidiary to be qualifying income. There is a risk that the U.S. Internal Revenue Service (“IRS”) could issue regulations or other guidance holding, or could assert, that the Fund’s income with respect to the Subsidiary will not be considered “qualifying income” for purposes of the Fund remaining qualified as a RIC for U.S. federal income tax purposes. In such circumstances, the Fund may be required to make changes to its operations, which may reduce the Fund’s ability to gain investment exposure to commodities. Fund

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shareholders may also experience adverse tax consequences in such circumstances.

Valuation Risk. The price the Fund could receive upon 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

As of the date of the Prospectus, the Fund has been in operation for less than one full calendar year and therefore does not report its performance information.

Management

Investment Adviser. BlackRock Fund Advisors.

Portfolio Managers. Alan Mason, Richard Mejzak and Greg Savage (the “Portfolio Managers”) are primarily responsible for the day-to-day management of the Fund. Each Portfolio Manager supervises a portfolio management team. Mr. Mason, Mr. Mejzak and Mr. Savage have been Portfolio Managers of the Fund since inception.

Purchase and Sale of Fund Shares

The Fund is an ETF. Individual shares of the Fund are listed on a national securities exchange. Most investors will buy and sell shares of the Fund through a broker-dealer. The price of Fund shares is based on market price, and 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). The Fund will only issue or redeem shares that have been aggregated into blocks of 50,000 shares or multiples thereof (“Creation Units”) to Authorized Participants who have entered into agreements with the Fund's distributor.

The Fund generally will issue or redeem Creation Units in return for a designated portfolio of securities (and an amount of cash) that the Fund specifies each day.

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

IS-SP-CMDY-0418

Investment Company Act file No.: 811-22649