August 1, 2013

(as revised February 21, 2014)

2013 Summary Prospectus

iShares 2014 AMT-Free Muni Term ETF  |  MUAC |  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 August 1, 2013, 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 ^® 2014 AMT-FREE MUNI TERM ETF

Ticker: MUAC

Stock Exchange: NYSE Arca

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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 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 1% of the average value of its portfolio.

Principal Investment Strategies

The Fund seeks to track the investment results of the S&P AMT-Free Municipal Series 2014 Index ^TM (the “Underlying Index”), which measures the performance of investment-grade, non-callable U.S. municipal bonds maturing in 2014. As of March 31, 2013, there were 3,193 issues in the Underlying Index.

The Underlying Index includes municipal bonds primarily from issuers that are state or local governments or agencies such that the interest on the bonds is exempt from U.S. federal income taxes and the federal alternative minimum tax (“AMT”). Each bond must have a rating of at least BBB- by Standard & Poor's Ratings Services, Baa3 by Moody’s Investors Service, Inc. (“Moody's”), or BBB- by Fitch, Inc. and must have a minimum maturity par amount of $2 million to be eligible for inclusion in the Underlying Index. To remain in the Underlying Index, bonds must maintain a minimum par amount greater than or equal to $2 million as of each rebalancing date. All bonds in the Underlying Index will mature after May

31 and before September 1 of the year referenced in the name of the Underlying Index. When a bond matures in the Underlying Index, an amount representing its value at maturity will be included in the Underlying Index throughout the remaining life of the Underlying Index, and any such amount will be assumed to earn a rate equal to the performance of the Standard & Poor's Financial Services LLC's, a subsidiary of The McGraw-Hill Companies, Inc., Weekly High Grade Index, which consists of Moody's Investment Grade-1 municipal tax-exempt notes that are not subject to federal AMT. The Underlying Index is a market value weighted index and is rebalanced after the market close on the last business day of each month.

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 the 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, duration, maturity or credit ratings and yield) and liquidity measures similar to those of the Underlying Index. The Fund may or may not hold all of the securities in the Underlying Index.

The Fund generally invests at least 80% of its assets in the securities of its Underlying Index, except during the last months of the Fund's operations, as described below. The Fund may invest the remainder of its assets in cash and cash equivalents (including money market funds affiliated with BFA), as well as in municipal bonds not included in the Underlying Index, but which BFA believes will help the Fund track its Underlying Index. The Fund will generally hold municipal bond securities issued by state and local municipalities whose interest payments are exempt from U.S. federal income tax, the federal AMT and a federal Medicare contribution tax of 3.8% on “net investment income,” including dividends, interest and capital gains. In the last months of operation, as the bonds held by the Fund mature, the proceeds will not be reinvested in bonds but instead will be held in cash and cash equivalents, including, without limitation, money market funds affiliated with BFA, AMT-free tax-exempt municipal notes, variable rate demand notes and obligations, tender option bonds and municipal commercial paper. These cash equivalents may not be included in the Underlying Index. By August 31, 2014, the Underlying Index is expected to consist entirely of cashed earned in this manner. Around the same

time, the Fund will wind up and terminate, and its net assets will be distributed to then-current shareholders. 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 the collateral received).

The Underlying Index is a product of an organization (the “Index Provider”) that 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. The Fund’s Index Provider is S&P Dow Jones Indices LLC (“S&P”), a subsidiary of McGraw Hill Financial, Inc.

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 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 in the Underlying Index or in the Fund's portfolio may underperform in comparison to the general securities markets or other asset classes.

Concentration Risk . To the extent that the Fund's investments are concentrated in a particular state, region, municipality, market, project type, industry, group of industries, or asset class, the Fund may be susceptible to loss due to adverse occurrences affecting that state, region, municipality, market, project type, industry, group of industries or asset class.

Credit Risk . The Fund is subject to the risk that debt issuers and other counterparties may not honor their obligations or may have their debt downgraded by ratings agencies.

Declining Yield Risk. During the final twelve months prior to the Fund's planned termination date, its 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.

Fluctuation of Yield and Liquidation Amount Risk . The Fund, unlike a direct investment in a municipal bond that has a level coupon payment and a fixed payment at maturity, will make distributions of income that vary over time. It is expected that an investment in the Fund, if held through maturity, will produce aggregate returns comparable

to a direct investment in a group of municipal bonds of similar credit quality and maturity. Unlike a direct investment in municipal bonds, the breakdown of returns between Fund distributions and liquidation proceeds are not predictable at the time of your investment. For example, at times during the Fund's existence it may make distributions at a greater (or lesser) rate than the coupon payments received on the Fund's portfolio, which will result in the Fund returning a lesser (or greater) amount on liquidation than would otherwise be the case. The rate of Fund distribution payments may adversely affect the tax characterization of your returns from an investment in the Fund relative to a direct investment in municipal bonds. If the amount you receive as liquidation proceeds upon the Fund's termination is higher or lower than your cost basis, you may experience a gain or loss for tax purposes.

Income Risk. The Fund's income may decline when interest rates fall. This decline can occur because the Fund must invest in lower-yielding bonds as bonds in its portfolio mature, bonds in the Underlying Index are substituted or the Fund otherwise needs to purchase additional bonds.

Index-Related Risk. There is no guarantee that the Fund will achieve a high degree of correlation to the Underlying Index and therefore 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 may occur from time to time and may not be identified and corrected for a period of time, and may have an

adverse impact on the Fund and its Shareholders.

Interest Rate Risk . An increase in interest rates may cause the value of fixed-income securities held by the Fund to decline.

Issuer Risk . Fund performance depends on the performance of individual securities to which the Fund has exposure. The Fund invests in municipal bonds of issuers that are primarily state or local governments or agencies. Changes to the financial condition or credit rating of an issuer of those securities may cause the value of the securities 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. The Fund invests a significant portion of its portfolio in municipal securities, which may be less liquid than taxable bonds.

Management Risk . As the Fund may not fully replicate the Underlying Index, it is subject to the risk that BFA's investment management 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 market downturns. The recent financial crisis has caused a decrease in the value and liquidity of many securities, including certain municipal securities, and has adversely affected many issuers of municipal securities and may continue to do so.

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 disruption in the creation/redemption process of the Fund. ANY OF THESE FACTORS, AMONG OTHERS, MAY LEAD TO THE FUND'S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV.

Municipal Securities Risk . Municipal securities can be significantly affected by political or economic changes as well as uncertainties in the municipal market related to taxation, legislative changes or the rights of municipal security holders. Municipal securities backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the inability to collect revenues for the project or from the assets.

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

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 Fund's 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 the 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.

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

Tracking Error Risk . Tracking error is the divergence of the Fund’s performance from that of the Underlying Index. Tracking error may occur because of differences between the securities held in the Fund’s portfolio and those included in the Underlying Index, pricing differences, transaction costs, the Fund’s holding of cash, differences in timing of the accrual of dividends, changes to the Underlying Index or the need to meet 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.

Transportation Industry Group Risk. The transportation industry group may

be adversely affected by economic changes, fuel prices, labor relations, insurance costs and government regulations.

Valuation Risk. The sale price the Fund could receive for a security may differ from the Fund's valuation of the security and may differ from the value used by the Underlying Index, particularly for securities that trade in low volume or volatile markets or that are valued using a fair value methodology. Because the bond market may be open on days when the Fund does not price its shares, the value of the securities in the Fund’s portfolio may change on days when shareholders will not be able to purchase or sell the Fund’s shares.