March 24, 2021

2021 Summary Prospectus

•  iShares International Developed Small Cap Value Factor ETF | ISVL | 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 March 16, 2021, 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.

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.

iSHARES^® INTERNATIONAL DEVELOPED SMALL CAP VALUE FACTOR ETF

Ticker: ISVL Stock Exchange: Cboe BZX

Investment Objective

The iShares International Developed Small Cap Value Factor ETF (the “Fund”) seeks to track the investment results of an index composed of international developed market small-capitalization stocks, excluding the U.S. and Korea, with prominent value characteristics.

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 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. BFA, the investment adviser to the Fund, has contractually agreed to waive a portion of its management fee so that the Fund’s total annual fund operating expenses after the fee waiver will not exceed 0.30% through March 31, 2023. The contractual waiver may be terminated prior to March 31, 2023 only upon written agreement of the Trust and BFA.

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	Fee Waiver	Total Annual Fund Operating Expenses After Fee Waiver
0.40%	None	0.00%	0.40%	(0.10)%	0.30%

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:

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1 Year	3 Years
$31	$106

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 track the investment results of the FTSE Developed ex US ex Korea Small Cap Focused Value Index (the “Underlying Index”), which is an objective, rules-based equity index provided by FTSE International Limited (the “Index Provider” or “FTSE”). The Underlying Index measures the performance of international developed market small-capitalization companies, excluding the U.S. and Korea, with prominent value factor characteristics, as determined by the Index Provider. The Underlying Index is a subset of the FTSE Developed ex US ex Korea Small Cap Index (the “Parent Index”), which measures the performance of the small-capitalization segment of the international developed market, excluding the U.S. and Korea, as defined by the Index Provider.

The construction of the Underlying Index begins with the Parent Index and excludes companies that are ranked in the least liquid 20% based on the 60-day average dollar value traded. The list of

eligible constituents is then narrowed to exclude the top 20% of Parent Index constituents with the highest risk based on a 12-month trailing realized volatility. The list is further narrowed to exclude the top 20% of Parent Index constituents with the highest leverage, which is measured by comparing a company’s total debt to its total assets. Following these three initial screens, the remaining companies are evaluated to exclude companies with a negative sentiment score and negative price momentum. The sentiment score is calculated using the number of upgrades for earnings per share and the number of downgrades for earnings per share for a company's current and next fiscal year. A company with more downgrades for earnings per share than upgrades will have a negative sentiment score. Negative price momentum is determined based on monthly price returns over the trailing 12 months, excluding the latest month. The remaining companies are then ranked based on a weighted composite score of three value factor metrics; price-to-book, price-to-earnings and price-to-cash flow from operations (the “Composite Score”). The number of stocks selected is based on 25% of the Parent Index by count. The selected securities are weighted in proportion to their float adjusted market capitalization with a country constraint of +/- 10% relative to the Parent Index to form a baseline or target composition (the “Target Index”). The Underlying Index will be reviewed monthly and rebalanced to the Target Index if either of the following conditions are met: (i)

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the Underlying Index’s Composite Score is less than 90% of the Target Index’s Composite Score; or (ii) the Underlying Index has fewer than 20% of the number of securities by count of the Parent Index. If no rebalance is triggered, the component securities of the Underlying Index and their weights will remain unchanged. The Underlying Index may not rebalance for a period of time and is typically comprised of between 450 - 550 components.

As of December 31, 2020, a significant portion of the Underlying Index is represented by securities of companies in the industrials and real estate industries or sectors. The components of the Underlying Index are likely to change over time. As of December 31, 2020, the Underlying Index was comprised of 503 components.

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 capitalization and industry weightings), fundamental characteristics (such as return variability 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 80% of its assets in the component securities and other instruments 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 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. The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund.

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 FTSE which is independent of the Fund 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

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concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities) and repurchase agreements collateralized by U.S. government securities 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 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 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, 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 exchange-traded funds (“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.

Calculation Methodology Risk. The Underlying Index relies on various sources of information to assess the criteria of issuers included in the Underlying Index, including information that may be based on assumptions and estimates. Neither the Fund nor BFA can offer assurances that the Underlying Index’s calculation methodology or sources of information will provide an accurate assessment of included issuers.

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

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

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.

Equity Securities Risk. Equity securities are subject to changes in value, and their values may be more volatile than those of other asset classes. The Underlying Index is comprised of common stocks, which 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.

Geographic Risk. A natural disaster could occur in a geographic region in which the Fund invests, which could adversely affect the economy or the business operations of companies in the

specific geographic region, causing an adverse impact on the Fund's investments in, or which are exposed to, the affected region.

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. Unusual market conditions may cause the Index Provider to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition.

Industrials Sector Risk. Companies in the industrials sector may be adversely affected by changes in the supply of and demand for products and services, product obsolescence, claims for environmental damage or product liability and changes in general economic conditions, among other factors.

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

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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.

Issuer Risk. The performance of the Fund depends on the performance of individual securities to which the Fund has exposure. 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. As the Fund will not fully replicate the Underlying Index, it is 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 issues, 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. ANY OF

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

National Closed Market Trading Risk. To the extent that the underlying securities and/or other assets held by the Fund trade on foreign exchanges or in foreign markets that may be closed when the securities exchange on which the Fund’s shares trade is open, there are likely to be deviations between the current price of such an underlying security and the last quoted price for the underlying security (i.e., the Fund’s quote from the closed foreign market). These deviations could result in premiums or discounts to the Fund’s NAV that may be greater than those experienced by other ETFs.

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.

Non-U.S. Securities Risk. Investments in the securities of non-U.S. issuers are subject to the risks associated with investing in those non-U.S. markets, such as heightened risks of inflation or nationalization. The Fund may lose money due to political, economic and geographic events affecting issuers of non-U.S. securities or non-U.S. markets. In addition, non-U.S. securities markets may trade a small number of securities and may be unable to respond effectively to changes in trading volume, potentially making prompt liquidation of holdings difficult or impossible at times. The Fund is specifically exposed to Asian Economic Risk and European Economic Risk.

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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.

Real Estate Investment Risk. Companies that invest in real estate (“Real Estate Companies”), such as real estate investment trusts (“REITs”) or real estate holding and operating companies, expose investors in the Fund to the risks of owning real estate directly, as well as to risks that relate specifically to the way in which Real Estate Companies are organized and operated. Real estate is highly sensitive to general and local economic conditions and developments, and characterized by intense competition and periodic overbuilding. Many Real Estate Companies, including REITs, utilize leverage (and some may be highly leveraged), which increases investment risk and the risk normally associated with debt financing, and could potentially magnify the Fund’s losses. Rising interest rates could result in higher costs of capital for Real Estate Companies, which could negatively affect a Real Estate Company's ability to meet its payment obligations or its

financing activity and could decrease the market prices for REITs and for properties held by such REITs.

Reliance on Trading Partners Risk. The Fund invests in countries or regions whose economies are heavily dependent upon trading with key partners. Any reduction in this trading may have an adverse impact on the Fund's investments.

Risk of Investing in Developed Countries. The Fund’s investment in developed country issuers may subject the Fund to regulatory, political, currency, security, economic and other risks associated with developed countries. Developed countries tend to represent a significant portion of the global economy and have generally experienced slower economic growth than some less developed countries. Certain developed countries have experienced security concerns, such as terrorism and strained international relations. Incidents involving a country’s or region’s security may cause uncertainty in its markets and may adversely affect its economy and the Fund’s investments. In addition, developed countries may be adversely impacted by changes to the economic conditions of certain key trading partners, regulatory burdens, debt burdens and the price or availability of certain commodities.

Risk of Investing in Japan. The Japanese economy may be subject to considerable degrees of economic, political and social instability, which could have a negative impact on Japanese securities. Since 2000, Japan’s economic growth rate has generally remained low relative to other advanced economies, and it may remain low in the future. In addition, Japan is

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subject to the risk of natural disasters, such as earthquakes, volcanic eruptions, typhoons and tsunamis, which could negatively affect the Fund. Japan’s relations with its neighbors have at times been strained, and strained relations may cause uncertainty in the Japanese markets and adversely affect the overall Japanese economy.

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-Capitalization Companies Risk. Compared to mid- and large-capitalization companies, small-capitalization companies may be less stable and more susceptible to adverse developments. In addition, the securities of small-capitalization companies may be more volatile and less liquid than those of mid- and large-capitalization companies.

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.

Structural Risk. The countries in which the Fund invests may be subject to

considerable degrees of economic, political and social instability.

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 Underlying Index, pricing differences (including, as applicable, differences between a security’s price at the local market close and the Fund's valuation of a security at the time of calculation of the Fund's NAV), transaction costs incurred by the Fund, the Fund’s holding of uninvested cash, differences in timing of the accrual of or the valuation of dividends or interest, the requirements to maintain pass-through tax treatment, portfolio transactions carried out to minimize the distribution of capital gains to shareholders, acceptance of custom baskets, 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, ESPECIALLY BEFORE THE FUND REACHES SUFFICIENT SCALE AND FURTHER BROADENS ITS HOLDINGS.

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

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asset and from the value used by the Underlying Index, 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.

Value Securities Risk. Securities issued by companies that may be

perceived as undervalued, particularly securities of a company that appear to trade at a significant discount to the company’s intrinsic value, 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). At other times, value securities may not perform as well as growth securities or the stock market in general, and may be out of favor with investors for varying periods of time.

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. Jennifer Hsui, Alan Mason, Greg Savage and Amy Whitelaw (the “Portfolio Managers”) are primarily responsible for the day-to-day management of the Fund. Each Portfolio Manager supervises a portfolio management team. Ms. Hsui, Mr. Mason, Mr. Savage and Ms. Whitelaw have been Portfolio Managers of the Fund since inception (2021).

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 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-ISVL-0321

Investment Company Act file No.: 811-09729