December 28, 2018

2018 Summary Prospectus

^► iShares MSCI Saudi Arabia ETF | KSA |  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 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 December 28, 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”) 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^® MSCI SAUDI ARABIA ETF

Ticker: KSA Stock Exchange: NYSE Arca

Investment Objective

The iShares MSCI Saudi Arabia ETF (the “Fund”) seeks to track the investment results of a broad-based index composed of Saudi Arabian equities.

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.

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
0.74%	None	None	0.74%

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
$76	$237	$411	$918

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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 20% of the average value of its portfolio.

Principal Investment Strategies

The Fund seeks to track the investment results of the MSCI Saudi Arabia IMI 25/50 Index (the “Underlying Index”), which consists of stocks traded primarily on the Saudi Arabian Stock Exchange. The Underlying Index is a free float-adjusted market capitalization-weighted index with a capping methodology applied to issuer weights so that no single issuer of a component exceeds 25% of the Underlying Index weight, and all issuers with a weight above 5% do not cumulatively exceed 50% of the Underlying Index weight. The Underlying Index is designed to measure the equity market in Saudi Arabia, upon the market opening to foreign investors, and may include large-, mid- or small-capitalization companies. As of August 31, 2018, a significant portion of the Underlying Index is represented by securities of companies in the chemicals, financials and materials industries or sectors. The components of the Underlying Index are likely to change over time.

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 keeping 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 90% of its assets in the component securities of the Underlying Index and in investments that have economic characteristics that are substantially identical to the component securities of the Underlying Index (i.e., depositary receipts representing securities of the Underlying Index) and may invest up to 10% of its assets in certain futures, options and swap contracts, cash and

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cash equivalents, including shares of money market funds advised by BFA or its affiliates, 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 Underlying Index is sponsored by MSCI Inc. (the “Index Provider” or “MSCI”), 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 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.

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.

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. 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.

Cash Transactions Risk. The Fund expects to effect all of its creations and redemptions solely for cash, rather than in-kind securities and, as described below, cash posting must be pre-funded to purchase Saudi 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

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

Chemicals Industry Risk. The chemicals industry may be significantly affected by intense competition, product obsolescence, raw materials prices, and government regulation, and may be subject to risks associated with the production, handling and disposal of hazardous components, and litigation arising out of environmental contamination.

Commodity Risk. The Fund invests in Saudi Arabian issuers that are susceptible to 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.

Currency Risk. Because the Fund's NAV is determined in U.S. dollars, the Fund's NAV could decline if the currency of a non-U.S. market in which the Fund invests depreciates against the U.S. dollar or if there are delays or limits on repatriation of such currency. Currency

exchange rates can be very volatile and can change quickly and unpredictably. As a result, the Fund's NAV may change quickly and without warning.

Custody Risk. Less developed securities markets are more likely to experience problems with the clearing and settling of trades, as well as the holding of securities by local banks, agents and depositories.

Cyber Security Risk. Failures or breaches of the electronic systems of the Fund, the Fund's adviser, distributor, and other service providers, the Index Provider, 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, the Index Provider, 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

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and debt securities upon the bankruptcy of the issuer.

Financials Sector Risk. Performance of companies in the financials sector may be adversely impacted by many factors, including, among others, changes in government regulations, economic conditions, and interest rates, credit rating downgrades, and decreased liquidity in credit markets. The extent to which the Fund may invest in a company that engages in securities-related activities or banking is limited by applicable law. The impact of changes in capital requirements and recent or future regulation of any individual financial company, or of the financials sector as a whole, cannot be predicted. In recent years, cyber-attacks and technology malfunctions and failures have become increasingly frequent in this sector and have caused significant losses to companies in this sector, which may negatively impact the Fund.

Geographic Risk. A natural disaster could occur in Saudi Arabia, which could adversely affect the economy or the business operations of companies in Saudi Arabia, causing an adverse impact on the Fund's investments in Saudi Arabia.

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.

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.

Large-Capitalization Companies Risk. Large-capitalization companies may be less able than smaller capitalization companies to adapt to changing market conditions. Large-capitalization companies may be more mature and subject to more limited growth potential compared with smaller capitalization companies. During different market cycles, the performance of large-capitalization companies has trailed the overall performance of the broader securities markets.

Management Risk. As the Fund may 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.

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

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TRADING AT A PREMIUM OR DISCOUNT TO NAV.

Materials Sector Risk. Companies in the materials sector may be adversely impacted by the volatility of commodity prices, changes in exchange rates, depletion of resources, over-production, litigation and changes in government regulations, among other factors.

National Closed Market Trading Risk. To the extent that the underlying securities 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.

Nationalization Risk. Investments in Saudi Arabia may be subject to loss due to expropriation or nationalization of assets and property or the imposition of restrictions on foreign investments and repatriation of capital.

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 Middle Eastern Economic Risk.

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.

Pre-Funding and Associated Risks. Saudi Arabian equities can only be purchased on a pre-funded basis, whereby the Fund or its broker (on behalf of the Fund), must deliver an estimated amount of local currency (the “Pre-Funding Amount”) to cover purchases before trade executions may take place. In the event that the Pre-Funding Amount is not delivered on time or is insufficient to purchase all the underlying securities in connection with a creation or portfolio rebalancing, trade executions would be delayed. This could result in higher brokerage

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guarantee costs for Authorized Participants in a creation or higher tracking error in the case of a portfolio rebalance.

Privatization Risk. The country in which the Fund invests has privatized, or has begun the process of privatizing, certain entities and industries. Privatized entities may lose money or be re-nationalized.

Reliance on Trading Partners Risk. The Fund invests in a country whose economy is heavily dependent upon trading with key partners. Any reduction in this trading may have an adverse impact on the Fund's investments. Through its holdings of securities of certain issuers, the Fund is specifically exposed to Asian Economic Risk and U.S. Economic Risk.

Risk of Investing in Emerging Markets. The Fund's investments in emerging market issuers may be subject to a greater risk of loss than investments in issuers located or operating in more developed markets. Emerging markets may be more likely to experience inflation, political turmoil and rapid changes in economic conditions than more developed markets. Emerging markets often have less uniformity in accounting and reporting requirements, less reliable securities valuations and greater risk associated with custody of securities than developed markets.

Risk of Investing in Saudi Arabia. The ability of foreign investors (such as the Fund) to invest in Saudi Arabian issuers is new and untested. Such ability could be restricted or revoked by the Saudi Arabian government at any time, and unforeseen risks could materialize due to foreign ownership in such securities. The economy of Saudi Arabia is

dominated by petroleum exports. A sustained decrease in petroleum prices could have a negative impact on all aspects of the economy. Investments in securities of Saudi Arabian issuers involves risks not typically associated with investments in securities of issuers in more developed countries that may negatively affect the value of the Fund’s investments. Such heightened risks may include, among others, expropriation and/or nationalization of assets, restrictions on and government intervention in international trade, confiscatory taxation, political instability, including authoritarian and/or military involvement in governmental decision making, armed conflict, crime and instability as a result of religious, ethnic and/or socioeconomic unrest. There remains the possibility that instability in the larger Middle East region could adversely impact the economy of Saudi Arabia, and there is no assurance of political stability in Saudi Arabia.

Saudi Arabia Broker Risk. There are a number of different ways of conducting transactions in equity securities in the Saudi Arabian market. The Fund generally expects to conduct its transactions in a manner in which the Fund would not be limited by Saudi Arabian regulations to a single broker. However, there may be a limited number of brokers who can provide services to the Fund, which may have an adverse impact on the prices, quantity or timing of Fund transactions.

Security Risk. The Middle East has experienced security concerns, such as terrorism and strained international relations. Incidents involving a country's or region's security may cause uncertainty in their markets and may

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adversely affect its economy and the Fund's investments.

Special Risk Considerations Relating to the QFI Regime and Investments in Saudi Arabian Equities. The Fund’s ability to achieve its investment objective depends on the ability of BFA as a QFI, and the Fund as a QFI Client, to obtain and maintain their respective authorizations from the CMA. Even if it obtains QFI Client approval, the Fund will not have an exclusive investment quota and will be subject to foreign investment limitations and other regulations imposed by the CMA on QFIs and QFI Clients, as well as local market participants. Any change in the QFI system generally, including the possibility of BFA or the Fund losing their respective QFI and QFI Client status, may adversely affect the Fund.

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), differences in transaction costs, 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, 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.

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 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.

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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. Supplemental information about the Fund’s performance is shown under the heading Total Return Information in the Supplemental Information section of the Prospectus.

Year by Year Returns¹ (Years Ended December 31)

¹ The Fund’s year-to-date return as of September 30, 2018 was 16.10%.

The best calendar quarter return during the period shown above was 25.37% in the 4th quarter of 2016; the worst was -10.49% in the 3rd quarter of 2016.

Updated performance information may be obtained by visiting our website at www.iShares.com or by calling 1-800-iShares (1-800-474-2737) (toll free).

Average Annual Total Returns

(for the periods ended December 31, 2017)

	One Year	Since Fund Inception
(Inception Date: 09/16/2015)
Return Before Taxes	5.15%	3.81%
Return After Taxes on Distributions2	4.14%	2.77%
Return After Taxes on Distributions and Sale of Fund Shares2	2.97%	2.45%
MSCI Saudi Arabia IMI 25/50 Index (Index returns do not reflect deductions for fees, expenses or taxes)	6.03%	4.78%

² 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.

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Management

Investment Adviser. BlackRock Fund Advisors.

Portfolio Managers. Rachel Aguirre, Diane Hsiung, 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. Hsiung, Ms. Hsui and Mr. Savage have been Portfolio Managers of the Fund since 2015. Mr. Mason has been a Portfolio Manager of the Fund since 2016. Ms. Aguirre and Ms. Whitelaw have been Portfolio Managers of the Fund since 2018.

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 specified amount of cash.

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 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-KSA-0119

Investment Company Act file No.: 811-09729