February 26, 2020

2020 Summary Prospectus

•  iShares iBonds Dec 2027 Term Treasury ETF | IBTH | NASDAQ

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 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 18, 2020, as amended and supplemented from time to time, are incorporated by reference into (legally made a part of) this Summary Prospectus.

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.

*The iShares iBonds Dec 2027 Term Treasury ETF may also conduct business as the iBonds Dec 2027 Term Treasury ETF.

iSHARES^® iBONDS DEC 2027 TERM TREASURY ETF

Ticker: IBTH Stock Exchange: NASDAQ

Investment Objective

The iShares iBonds Dec 2027 Term Treasury ETF (the “Fund”) seeks to track the investment results of an index composed of U.S. Treasury bonds maturing in 2027.

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 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 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 by investing in other investment companies. The impact of Acquired Fund Fees and Expenses is included in the total returns of the Fund. Acquired Fund Fees and Expenses are not included in the calculation of the ratio of expenses to average net assets shown in the Financial Highlights section of the Fund's prospectus (the “Prospectus”).

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 Expenses1	Acquired Fund Fees and Expenses1,2	Total Annual Fund Operating Expenses	Fee Waiver1,2	Total Annual Fund Operating Expenses After Fee Waiver
0.07%	None	0.00%	0.00%	0.07%	(0.00)%	0.07%

1

The amount rounded to 0.00%.

2

BFA has contractually agreed to waive a portion of its management fees in an amount equal to the Acquired Fund Fees and Expenses, if any, attributable to investments by the Fund in other funds advised by BFA or its affiliates through the termination date of the Fund, on or about December 15, 2027. The contractual waiver may be terminated prior to the Fund's termination only upon the written agreement of the Trust and BFA.

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

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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
$7	$23

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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.

Principal Investment Strategies

The Fund seeks to meet its investment objective generally by investing in individual securities which satisfy the criteria of the ICE 2027 Maturity US Treasury Index (the “Underlying Index”). The Fund may also invest in short-term paper, cash and cash equivalents, including shares of money market funds advised by BFA or its affiliates.

The Fund is a term fund that will terminate on or about December 15, 2027, at which time it will distribute its remaining net assets to shareholders pursuant to a plan of liquidation. The Fund does not seek to return any predetermined amount at maturity or in periodic distributions. The Underlying Index consists of publicly-issued U.S. Treasury securities that are scheduled to mature after December 31, 2026 and before December 16, 2027. Qualifying securities are U.S. Treasury notes and bonds having $1 billion or more of outstanding face value, excluding amounts held by the Federal Reserve System Open Market Account (“SOMA”). In addition, the securities in the Underlying Index must have a fixed coupon schedule and be denominated in U.S. dollars. Excluded from the Underlying Index are inflation-linked

securities, Treasury bills, cash management bills, any government agency debt issued with or without a government guarantee and zero-coupon issues that have been stripped from coupon-paying bonds. However, the amounts outstanding of qualifying securities in the Underlying Index are not reduced by any individual components of such securities (i.e., coupon or principal) that have been stripped after inclusion in the Underlying Index.

The Underlying Index is market value weighted based on amounts outstanding reduced by amounts held by the Federal Reserve SOMA. Accrued interest is calculated assuming next-day settlement. The Underlying Index is rebalanced on the last calendar day of the month, based on information available up to and including the third business day before the last business day of the month. New issues must settle on or before the calendar month end rebalancing date in order to qualify for the upcoming month. The securities in the Underlying Index are updated on the last calendar day of each month until six months prior to maturity. Cash flows from bond payments that are received during the month are retained in the Underlying Index until the end of the month and then are removed as part of the rebalancing. Beginning June 30, 2027, the Underlying Index will not remove interest payments and matured securities at each rebalancing but instead will retain those amounts as a growing cash position throughout the remaining life of the Underlying Index. As the Fund approaches its termination date, its holdings of money market funds or similar funds may increase, causing the Fund to incur fees and expenses of such funds. By December

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15, 2027, the Underlying Index value will be represented almost entirely by cash as no securities will remain in the Underlying Index.

BFA uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued.

Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by aiming to keep portfolio turnover low in comparison to actively managed investment companies.

BFA uses a representative sampling indexing strategy to manage the Fund. “Representative sampling” is an indexing strategy that involves investing in a representative sample of securities that collectively has an investment profile similar to that of an applicable underlying index. The securities selected are expected to have, in the aggregate, investment characteristics (based on factors such as market value and industry weightings), fundamental characteristics (such as return variability, duration, maturity, credit ratings and yield) and liquidity measures similar to those of an applicable underlying index. The Fund may or may not hold all of the securities in the Underlying Index.

The Fund generally will invest at least 90% of its assets in the component securities of the Underlying Index, except during the last months of the

Fund’s operations, as described below, and may invest up to 10% of its assets in certain futures, options and swap contracts, cash and cash equivalents, including shares of money market funds advised by BFA or its affiliates (“BlackRock Cash Funds”), as well as in securities not included in the Underlying Index, but which BFA believes will help the Fund track the Underlying Index. From time to time when conditions warrant, however, the Fund may invest at least 80% of its assets in the component securities of the Underlying Index and may invest up to 20% of its assets in certain futures, options and swap contracts, cash and cash equivalents, including shares of BlackRock Cash Funds, as well as in securities not included in the Underlying Index, but which BFA believes will help the Fund track the Underlying Index.

The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund. In the last months of operation, as the bonds held by the Fund mature, the proceeds will not be reinvested by the Fund in bonds but instead will be held in cash and cash equivalents. By December 15, 2027, the Underlying Index is expected to consist almost entirely of cash earned in this manner. On or around this date, the Fund will wind up and terminate, and its net assets will be distributed to then-current shareholders pursuant to a plan of liquidation.

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

The Underlying Index is sponsored by ICE Data Indices, LLC or its affiliates (collectively, the “Index Provider” or “IDI”), which is independent of the Fund

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and BFA. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index.

Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities), repurchase agreements collateralized by U.S. government securities, and securities of state or municipal governments and their political subdivisions are not considered to be issued by members of any industry.

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. 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 Underlying Index or 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 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 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, 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 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.

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.

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Cybersecurity Risk. Failures or breaches of the electronic systems of the Fund, the Fund's adviser, distributor, the Index Provider and other service providers, 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 Index Provider and other service providers, market makers, Authorized Participants or issuers of securities in which the Fund invests.

Declining Yield Risk. During the six months prior to the Fund’s planned termination date, the Fund’s yield will generally tend to move toward prevailing money market rates and may be lower than the yields of the bonds previously held by the Fund and lower than prevailing yields for bonds in the market.

Income Risk. The Fund's income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower-yielding bonds as bonds in its portfolio mature, are near maturity, or bonds in the Underlying Index are substituted, or the Fund otherwise needs to purchase additional bonds. As the Fund does not seek to return any predetermined amount at maturity or in periodic distributions, the amount of income generated by the Fund may vary during its term. In addition, the Fund's income

is expected to decline in the months leading up to its maturity date because its portfolio will increasingly consist of cash and cash equivalents.

Index-Related Risk. There is no guarantee that the Fund’s investment results will have a high degree of correlation to those of the Underlying Index or that the Fund will achieve its investment objective. Market disruptions and regulatory restrictions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track the Underlying Index. Errors in index data, index computations or the construction of the Underlying Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders.

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, 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.

Management Risk. As the Fund will not fully replicate the Underlying Index, it is

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subject to the risk that BFA's investment strategy may not produce the intended results.

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.

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

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

inadequate to address significant operational risks.

Passive Investment Risk. The Fund is not actively managed, and BFA generally does not attempt to take defensive positions under any market conditions, including declining markets.

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.

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 in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any 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.

Tracking Error Risk. The Fund may be subject to tracking error, which is the divergence of the Fund’s performance from that of the Underlying Index. Tracking error may occur because of differences between the securities and other instruments held in the Fund’s portfolio and those included in the

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Underlying Index, pricing differences, transaction costs incurred by the Fund, the Fund’s holding of uninvested cash, differences in timing of the accrual of or the valuation of distributions, the requirements to maintain pass-through tax treatment, portfolio transactions carried out to minimize the distribution of capital gains to shareholders, changes to the Underlying Index or the costs to the Fund of complying with various new or existing regulatory requirements. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because the Fund incurs fees and expenses, while the Underlying Index does not. BFA EXPECTS THAT THE FUND MAY EXPERIENCE HIGHER TRACKING ERROR THAN IS TYPICAL FOR SIMILAR INDEX ETFs.

U.S. Treasury Obligations Risk. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund's U.S. Treasury obligations to decline.

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.

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Management

Investment Adviser. BlackRock Fund Advisors.

Portfolio Managers. James Mauro and Scott Radell (the “Portfolio Managers”) are primarily responsible for the day-to-day management of the Fund. Each Portfolio Manager supervises a portfolio management team. Mr. Mauro and Mr. Radell have been Portfolio Managers of the Fund since inception.

Purchase and Sale of Fund Shares

The Fund is an exchange-traded fund (commonly referred to as 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. Certain states and localities may exempt from tax distributions attributable to interest from U.S. federal government obligations. 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-IBTH-0220

Investment Company Act file No.: 811-09729