497K 1 d815775d497k.htm BLACKROCK CORE BOND PORTFOLIO - SERVICE BLACKROCK CORE BOND PORTFOLIO - SERVICE
JANUARY 28, 2015
Summary Prospectus
BlackRock Funds II  |  Service Shares
► BlackRock Core Bond Portfolio
  Service: CMCBX
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://www.blackrock.com/prospectus. You can also get this information at no cost by calling (800) 537-4942 or by sending an e-mail request to prospectus.request@blackrock.com, or from your financial professional. The Fund’s prospectus and statement of additional information, both dated January 28, 2015, as amended and supplemented from time to time, are incorporated by reference into (legally made a part of) this Summary Prospectus.
This Summary Prospectus contains information you should know before investing, including information about risks. Please read it before you invest and keep it for future reference.
The Securities and Exchange Commission and the Commodity Futures Trading Commission have not approved or disapproved these securities or passed upon the adequacy of this Summary Prospectus. Any representation to the contrary is a criminal offense.
Not FDIC Insured • May Lose Value • No Bank Guarantee

Summary Prospectus
Key Facts About BlackRock Core Bond Portfolio
Investment Objective
The investment objective of the BlackRock Core Bond Portfolio (the “Core Bond Fund” or the “Fund”) is to seek to maximize total return, consistent with income generation and prudent investment management.
Fees and Expenses of the Fund
This table describes the fees and expenses that you may pay if you buy and hold Service Shares of the Fund.
Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment) 		  Service
Shares
Management Fee1   0.34%
Distribution and/or Service (12b-1) Fees   0.25%
Other Expenses   0.23%
Interest Expense 0.01%  
Miscellaneous Other Expenses 0.22%  
Total Annual Fund Operating Expenses1,2   0.82%
Fee Waivers and/or Expense Reimbursements3   (0.02)%
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements3   0.80%
  
1 Management Fee has been restated to reflect current fees.
2 The Total Annual Fund Operating Expenses do not correlate to the ratio of expenses to average net assets in the Fund’s most recent annual report, which does not include the restatement of the Management Fee to reflect current fees.
3 As described in the “Management of the Funds” section on page 40, BlackRock Advisors, LLC has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) to 0.79% of average daily net assets until February 1, 2016. The Fund may have to repay some of these waivers and reimbursements to BlackRock Advisors, LLC in the two years following such waivers and/or reimbursements. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested trustees of the Fund or by a vote of a majority of the outstanding voting securities of the Fund.
Example:
This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem 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
Service Shares $82 $260 $453 $1,012
  
Portfolio Turnover:
The Fund pays 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 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 702% of the average value of its portfolio.
Principal Investment Strategies of the Fund
The Core Bond Fund normally invests at least 80% of its assets in bonds and maintains an average portfolio duration that is within ±20% of the duration of the benchmark. As of December 31, 2014, the average duration of the benchmark, the Barclays U.S. Aggregate Bond Index, was 5.07 years, as calculated by BlackRock.
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The Core Bond Fund may invest up to 25% of its assets in assets of foreign issuers, of which 10% (as a percentage of the Fund’s assets) may be invested in emerging markets issuers. Up to 10% of the Core Bond Fund’s assets may be exposed to non-US currency risk. A bond of a foreign issuer, including an emerging market issuer, will not count toward the 10% limit on non-US currency exposure if the bond is either (i) US dollar-denominated or (ii) non-US dollar-denominated, but hedged back to US dollars.
The Core Bond Fund only buys securities that are rated investment grade at the time of purchase by at least one major rating agency or determined by the Fund’s management team to be of similar quality. Split rated bonds will be considered to have the higher credit rating.
The management team evaluates sectors of the bond market and individual securities within these sectors. The management team selects bonds from several sectors including: U.S. Treasuries and agency securities, commercial and residential mortgage-backed securities, collateralized mortgage obligations (“CMOs”), asset-backed securities and corporate bonds.
The Core Bond Fund may buy or sell options or futures on a security or an index of securities, or enter into credit default swaps and interest rate or foreign currency transactions, including swaps (collectively, commonly known as derivatives). The Fund may use derivative instruments to hedge its investments or to seek to enhance returns. The Core Bond Fund may seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as reverse repurchase agreements or dollar rolls).
The Core Bond Fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies.
Principal Risks of Investing in the Fund
Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund.
■ Borrowing Risk — Borrowing may exaggerate changes in the net asset value of Fund shares and in the return on the Fund’s portfolio. Borrowing will cost the Fund interest expense and other fees. The costs of borrowing may reduce the Fund’s return. Borrowing may cause the Fund to liquidate positions when it may not be advantageous to do so to satisfy its obligations.
■ Debt Securities Risk — Debt securities, such as bonds, involve interest rate risk, credit risk, extension risk, and prepayment risk, among other things.
  Interest Rate Risk — The market value of bonds and other fixed-income securities changes in response to interest rate changes and other factors. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Fund may be subject to a greater risk of rising interest rates due to the current period of historically low rates. For example, if interest rates increase by 1%, assuming a current portfolio duration of ten years, and all other factors being equal, the value of the Fund’s investments would be expected to decrease by 10%. The magnitude of these fluctuations in the market price of bonds and other fixed-income securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Fund’s investments will not affect interest income derived from instruments already owned by the Fund, but will be reflected in the Fund’s net asset value. The Fund may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Fund management. To the extent the Fund invests in debt securities that may be prepaid at the option of the obligor (such as mortgage-backed securities), the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Fund) when interest rates rise. Moreover, because rates on certain floating rate debt securities typically reset only periodically, changes in prevailing interest rates (and particularly sudden and significant changes) can be expected to cause some fluctuations in the net asset value of the Fund to the extent that it invests in floating rate debt securities. These basic principles of bond prices also apply to U.S. Government securities. A security backed by the “full faith and credit” of the U.S. Government is guaranteed only as to its stated interest rate and face value at maturity, not its current market price. Just like other fixed-income securities, government-guaranteed securities will fluctuate in value when interest rates change. A general rise in interest rates has the potential to cause investors to move out of fixed-income securities on a large scale, which may increase redemptions from funds that hold large amounts of fixed-income securities. Heavy redemptions could cause the Fund to sell assets at inopportune times or at a loss or depressed value and could hurt the Fund’s performance.
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  Credit Risk — Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will not be able to make principal and interest payments when due. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also affect the value of the Fund’s investment in that issuer. The degree of credit risk depends on the issuer’s financial condition and on the terms of the securities.
  Extension Risk — When interest rates rise, certain obligations will be paid off by the obligor more slowly than anticipated, causing the value of these obligations to fall.
  Prepayment Risk — When interest rates fall, certain obligations will be paid off by the obligor more quickly than originally anticipated, and the Fund may have to invest the proceeds in securities with lower yields.
■ Derivatives Risk — The Fund’s use of derivatives may reduce the Fund’s returns and/or increase volatility. Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund’s use of derivatives is that the fluctuations in their values may not correlate perfectly with the overall securities markets. Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. Derivatives also may expose the Fund to greater risk and increase its costs. Certain transactions in derivatives involve substantial leverage risk and may expose the Fund to potential losses that exceed the amount originally invested by the Fund. The U.S. Government is in the process of adopting and implementing regulations governing derivatives markets, including mandatory clearing of certain derivatives, margin, reporting and registration requirements. The ultimate impact of the regulations remains unclear. Additional U.S. or other regulations may make derivatives more costly, may limit the availability of derivatives, or may otherwise adversely affect the value or performance of derivatives. Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority that could affect the character, timing and amount of the Fund’s taxable income or gains and distributions.
■ Dollar Rolls Risk — Dollar rolls involve the risk that the market value of the securities that the Fund is committed to buy may decline below the price of the securities the Fund has sold. These transactions may involve leverage.
■ Emerging Markets Risk — Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging securities markets have far lower trading volumes and less liquidity than developed markets.
■ Foreign Securities Risk — Foreign investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. These risks include:
■ The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory oversight.
■ Changes in foreign currency exchange rates can affect the value of the Fund’s portfolio.
■ The economies of certain foreign markets may not compare favorably with the economy of the United States with respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of payments position.
■ The governments of certain countries may prohibit or impose substantial restrictions on foreign investments in their capital markets or in certain industries.
■ Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as does the United States and may not have laws to protect investors that are comparable to U.S. securities laws.
■ Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of securities not typically associated with settlement and clearance of U.S. investments.
■ High Portfolio Turnover Risk — The Fund may engage in active and frequent trading of its portfolio securities. High portfolio turnover (more than 100%) may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other securities. The sale of Fund portfolio securities may result in the realization and/or distribution to shareholders of higher capital gains or losses as compared to a fund with less active trading policies. These effects of higher than normal portfolio turnover may adversely affect Fund performance. In addition, investment in
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  mortgage dollar rolls and participation in TBA transactions may significantly increase the Fund’s portfolio turnover rate. A TBA transaction is a method of trading mortgage-backed securities where the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount, and price at the time the contract is entered into but the mortgage-backed securities are delivered in the future, generally 30 days later.
■ Leverage Risk — Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet any required asset segregation requirements. Increases and decreases in the value of the Fund’s portfolio will be magnified when the Fund uses leverage.
■ Liquidity Risk — Liquidity risk exists when particular investments are difficult to purchase or sell. The Fund’s investment in illiquid securities may reduce the returns of the Fund because it may be difficult to sell the illiquid securities at an advantageous time or price. To the extent that the Fund’s principal investment strategies involve derivatives or securities with substantial market and/or credit risk, the Fund will tend to have the greatest exposure to liquidity risk. Liquid investments may become illiquid after purchase by the Fund, particularly during periods of market turmoil. Illiquid investments may be harder to value, especially in changing markets, and if the Fund is forced to sell these investments to meet redemption requests or for other cash needs, the Fund may suffer a loss. In addition, when there is illiquidity in the market for certain securities, the Fund, due to limitations on illiquid investments, may be subject to purchase and sale restrictions.
■ Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.
■ Mortgage- and Asset-Backed Securities Risks — Mortgage- and asset-backed securities represent interests in “pools” of mortgages or other assets, including consumer loans or receivables held in trust. Mortgage- and asset-backed securities are subject to credit, interest rate, prepayment and extension risks. These securities also are subject to risk of default on the underlying mortgage or asset, particularly during periods of economic downturn. Small movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of certain mortgage-backed securities.
■ Repurchase Agreements and Purchase and Sale Contracts Risk — If the other party to a repurchase agreement or purchase and sale contract defaults on its obligation under the agreement, the Fund may suffer delays and incur costs or lose money in exercising its rights under the agreement. If the seller fails to repurchase the security in either situation and the market value of the security declines, the Fund may lose money.
■ Reverse Repurchase Agreements Risk — Reverse repurchase agreements involve the sale of securities held by the Fund with an agreement to repurchase the securities at an agreed-upon price, date and interest payment. Reverse repurchase agreements involve the risk that the other party may fail to return the securities in a timely manner or at all. The Fund could lose money if it is unable to recover the securities and the value of the collateral held by the Fund, including the value of the investments made with cash collateral, is less than the value of securities. These events could also trigger adverse tax consequences to the Fund.
■ U.S. Government Issuer Risk — Treasury obligations may differ in their interest rates, maturities, times of issuance and other characteristics. Obligations of U.S. Government agencies and authorities are supported by varying degrees of credit but generally are not backed by the full faith and credit of the U.S. Government. No assurance can be given that the U.S. Government will provide financial support to its agencies and authorities if it is not obligated by law to do so.
Performance Information
The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. The table compares the Fund’s performance to that of the Barclays U.S. Aggregate Bond Index. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance, including its current net asset value, can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at 800-882-0052.
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Service Shares
ANNUAL TOTAL RETURNS
BlackRock Core Bond Portfolio
As of 12/31
During the ten-year period shown in the bar chart, the highest return for a quarter was 6.05% (quarter ended September 30, 2009) and the lowest return for a quarter was -5.86% (quarter ended September 30, 2008).
As of 12/31/14
Average Annual Total Returns 		1 Year 5 Years 10 Years
BlackRock Core Bond Portfolio — Service Shares      
Return Before Taxes 6.36% 4.89% 4.07%
Return After Taxes on Distributions 5.12% 3.62% 2.59%
Return After Taxes on Distributions and Sale of Fund Shares 3.59% 3.27% 2.56%
Barclays U.S. Aggregate Bond Index
(Reflects no deduction for fees, expenses or taxes) 		5.97% 4.45% 4.71%
  
After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Investment Manager
The Fund’s investment manager is BlackRock Advisors, LLC (“BlackRock”).
Portfolio Managers
Name Portfolio Manager
of the Fund Since 		Title
Rick Rieder 2010 Chief Investment Officer of Fixed Income,
Fundamental Portfolios of BlackRock, Inc.
Bob Miller 2011 Managing Director of BlackRock, Inc.
  
Purchase and Sale of Fund Shares
You may purchase or redeem shares of the Fund each day the New York Stock Exchange (“NYSE”) is open. To purchase or sell shares you should contact your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock, The PNC Financial Services Group, Inc. (“PNC”) and their respective affiliates) (each a “Financial Intermediary”), or, if you hold your shares through the Fund, you should contact the Fund by phone at (800) 537-4942, by mail (c/o BlackRock Funds, P.O. Box 9819, Providence, Rhode Island 02940-8019), or by the Internet at www.blackrock.com/funds. The Fund’s initial and subsequent investment minimums generally are as follows, although the Fund may reduce or waive the minimums in some cases:
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  Service Shares
Minimum Initial Investment $5,000
Minimum Additional Investment There is no minimum amount for additional investments.
  
Tax Information
The Fund’s dividends and distributions may be subject to Federal income taxes and may be taxed as ordinary income or capital gains, unless you are a tax-exempt investor or are investing through a retirement plan, in which case you may be subject to Federal income tax upon withdrawal from such tax-deferred arrangements.
Payments to Broker/Dealers and Other Financial Intermediaries
If you purchase shares of the Fund through a Financial Intermediary, the Fund and BlackRock Investments, LLC, the Fund’s distributor, or its affiliates may pay the Financial Intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the Financial Intermediary and your individual financial professional to recommend the Fund over another investment. Ask your individual financial professional or visit your Financial Intermediary’s website for more information.
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INVESTMENT COMPANY ACT FILE # 811-22061
BlackRock Core Bond Portfolio — Service
SPRO-CB-SVC-0115