Summary Prospectus by Investment Company - Form 497K

BlackRock LifePath^® ESG Index 2070 Fund

Management Fee^1,2

Distribution and/or Service (12b-1) Fees

Other Expenses^1,3,4

Administration Fees¹

Independent Expenses^3,4

Acquired Fund Fees and Expenses¹

Total Annual Fund Operating Expenses

Fee Waivers and/or Expense Reimbursements^1,2,4

Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements^1,2,4

BlackRock Advisors, LLC ("BAL") and BFA have contractually agreed to reimburse the Fund for Acquired Fund Fees and Expenses up to a maximum amount equal to the combined Management Fee and Administration Fee of each share class through June 30, 2026. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

As described in the "Management of the Fund" section of the Fund's prospectus beginning on page 49, BFA has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to BFA indirectly through its investment in money market funds managed by BFA or its affiliates, through June 30, 2026. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

Other Expenses are based on estimated amounts for the Fund's current fiscal year.

Independent Expenses consist of the Fund's allocable portion of the fees and expenses of the independent trustees of the Trust, counsel to such independent trustees and the independent registered public accounting firm that provides audit services to the Fund. BAL and BFA have contractually agreed to reimburse, or provide offsetting credits to, the Fund for Independent Expenses through June 30, 2035. After giving effect to such contractual arrangements, Independent Expenses will be 0.00%. Such contractual arrangements may not be terminated prior to July 1, 2035 without the consent of the Board of Trustees of the Trust.

Investor A Shares

Institutional Shares

45

40

35

30

25

20

15

10

5

0

Equity Securities Risk - Stock markets are volatile. The price of equity securities fluctuates based on changes in a company's financial condition and overall market and economic conditions.

Investments in Underlying Funds Risk - Because the Fund invests substantially all of its assets in Underlying Funds, its investment performance is related to the performance of the Underlying Funds. The Fund's net asset value will change with changes in the value of the Underlying Funds and other securities in which it invests. An investment in the Fund will entail more direct and indirect costs and expenses than a direct investment in the Underlying Funds.

Allocation Risk - The Fund's ability to achieve its investment objective depends upon the Fund's asset class allocation and the mix of Underlying Funds. There is a risk that the asset class allocation or the combination of Underlying Funds may be incorrect in view of actual market conditions. In addition, the asset allocation or the combination of Underlying Funds determined by BFA could result in underperformance as compared to funds with similar investment objectives and strategies.

Retirement Income Risk - The Fund does not provide a guarantee that sufficient capital appreciation will be achieved to provide adequate income at and through retirement. The Fund also does not ensure that you will have assets in your account sufficient to cover your retirement expenses or that you will have enough saved to be able to retire in the target year identified in the Fund's name; this will depend on the amount of money you have invested in the Fund, the length of time you have held your investment, the returns of the markets over time, the amount you spend in retirement, and your other assets and income sources.

Risk of ESG Investing - The Fund intends to invest a portion of its assets in Underlying Funds that seek to maximize exposure to companies with higher ESG ratings. This may affect the Fund's exposure to certain companies or industries and the Fund will forgo certain investment opportunities. The Fund's results may be lower than other funds that do not seek to invest in companies based on ESG ratings and/or screen out certain companies or industries. The index provider for an Underlying Fund's underlying index seeks to identify companies that it believes may have higher ESG ratings, but investors may differ in their views of ESG characteristics. Additionally, certain Underlying Funds may not screen out investments based on certain ESG standards. As a result, the Fund may invest in companies that do not reflect the beliefs and values of any particular investor.

Affiliated Fund Risk - In managing the Fund, BFA will have authority to select and substitute underlying funds and ETFs. BFA may be subject to potential conflicts of interest in selecting underlying funds and ETFs because the fees paid to BFA by some underlying funds and ETFs are higher than the fees paid by other underlying funds and ETFs. However, BFA is a fiduciary to the Fund and is legally obligated to act in the Fund's best interests when selecting underlying funds and ETFs. If an underlying fund or ETF holds interests in an affiliated fund, the Fund may be prohibited from purchasing shares of that underlying fund or ETF.

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. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class.

Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. 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.

Asset Class Risk - Securities and other assets or financial instruments in an 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 an ETF, and none of those authorized participants is obligated to engage in creation and/or redemption transactions. An ETF 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 an ETF and no other authorized participant is able to step forward to create or redeem creation units, ETF shares may be more likely to trade at a premium or discount to net asset value and possibly face trading halts or delisting.

Calculation Methodology Risk - An ETF's index provider relies on various sources of information to assess the criteria of securities included in the underlying index (or its parent index), including information that may be based on assumptions and estimates. Neither the Fund nor BFA can offer assurances that an ETF's index provider's calculation methodology or sources of information will provide an accurate assessment of included components.

Concentration Risk - To the extent that an underlying index of an Underlying Fund is concentrated in the securities of companies, a particular market, industry, group of industries, sector or asset class, country, region or group of countries, that Underlying Fund may be adversely affected by the performance of those securities, may be subject to increased price volatility and may be more susceptible to adverse economic, market, political or regulatory occurrences affecting that market, industry, group of industries, sector or asset class, country, region or group of countries.

Depositary Receipts Risk - Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. In addition to investment risks associated with the underlying issuer, depositary receipts expose the Fund to additional risks associated with the non-uniform terms that apply to depositary receipt programs, credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency risk and the risk of an illiquid market for depositary receipts. The issuers of unsponsored depositary receipts are not obligated to disclose information that is, in the United States, considered material. Therefore, there may be less information available regarding these issuers and there may not be a correlation between such information and the market value of the depositary receipts. While depositary receipts provide an alternative to directly purchasing underlying foreign securities in their respective markets and currencies, they continue to be subject to many of the risks associated with investing directly in foreign securities, including political, economic, and currency risk.

Derivatives Risk - The Fund's use of derivatives may increase its costs, reduce the Fund's returns and/or increase volatility. Derivatives involve significant risks, including:

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, or the U.S. Government with respect to certain countries, may prohibit or impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer currency, securities, derivatives or other assets.

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.

The Fund's claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the foreign country, accruals in the Fund's net asset value for such refunds may be written down partially or in full, which will adversely affect the Fund's net asset value.

The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries as well as acts of war in the region. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Fund's investments.

Geographic Risk - Some of the companies in which the Fund invests are located in parts of the world that have historically been prone to natural disasters, such as earthquakes, tornadoes, volcanic eruptions, droughts, floods, hurricanes or tsunamis, and are economically sensitive to environmental events. Any such event may adversely impact the economies of these geographic areas or business operations of companies in these geographic areas, causing an adverse impact on the value of the Fund.

Index-Related Risk - There is no guarantee that an Underlying Fund's investment results will have a high degree of correlation to those of its underlying index or that the Underlying Fund will achieve its investment objective. Market disruptions or high volatility, other unusual market circumstances and regulatory restrictions could have an adverse effect on an Underlying Fund's ability to adjust its exposure to the required levels in order to track its underlying index. Errors in index data, index computations or the construction of an 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 an Underlying Fund and its shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to postpone a scheduled rebalance. This could cause an underlying index to vary from its normal or expected composition.

Issuer Risk - Fund performance 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.

Large Shareholder and Large-Scale Redemption Risk - Certain shareholders, including a third-party investor, the Fund's adviser or an affiliate of the Fund's adviser, or another entity, may from time to time own or manage a substantial amount of Fund shares or may invest in the Fund and hold its investment for a limited period of time. There can be no assurance that any large shareholder or large group of shareholders would not redeem their investment or that the size of the Fund would be maintained. Redemptions of a large number of Fund shares by these shareholders may adversely affect the Fund's liquidity and net assets. These redemptions may force the Fund to sell portfolio securities to meet redemption requests when it might not otherwise do so, which may negatively impact the Fund's net asset value and increase the Fund's brokerage costs and/or accelerate the realization of taxable income and cause the Fund to make taxable distributions to its shareholders earlier than the Fund otherwise would have. In addition, under certain circumstances, non-redeeming shareholders may be treated as receiving a disproportionately large taxable distribution during or with respect to such tax year. The Fund also may be required to sell its more liquid Fund investments to meet a large redemption, in which case the Fund's remaining assets may be less liquid, more volatile, and more difficult to price. In addition, large redemptions can result in a Fund's current expenses being allocated over a smaller asset base, which generally results in an increase in a Fund's expense ratio. Because large redemptions can adversely affect a portfolio manager's ability to implement a fund's investment strategy, each Fund also reserves the right to redeem in-kind, subject to certain conditions. In addition, large purchases of Fund shares may adversely affect the Fund's performance to the extent that the Fund is delayed in investing new cash and is required to maintain a larger cash position than it ordinarily would, diluting its investment returns.

Management Risk - As an Underlying Fund may not fully replicate its underlying index, it is subject to the risk that the Underlying Fund's investment manager's investment management strategy may not produce the intended results.

National Closed Market Trading Risk - To the extent that the underlying securities or other instruments held by an ETF trade on foreign exchanges or in foreign markets that may be closed when the securities exchange on which the ETF'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 ETF's quote from the closed foreign market). The impact of a closed foreign market on the Fund is likely to be greater where a large portion of the Fund's underlying securities or other instruments trade on that closed foreign market or when the foreign market is closed for unscheduled reasons. These deviations could result in premiums or discounts to the ETF's net asset value that may be greater than those experienced by other ETFs.

Passive Investment Risk - Because BFA does not select individual companies in the underlying indexes for certain Underlying Funds, those Underlying Funds may hold securities of companies that present risks that an investment adviser researching individual securities might seek to avoid.

Real Estate-Related Securities Risk - The main risk of real estate-related securities is that the value of the underlying real estate may go down. Many factors may affect real estate values. These factors include both the general and local economies, vacancy rates, changes in rent schedules, tenant bankruptcies, the ability to re-lease space under expiring leases on attractive terms, the amount of new construction in a particular area, the laws and regulations (including zoning, environmental and tax laws) affecting real estate and the costs of owning, maintaining and improving real estate. The availability of mortgage financing and changes in interest rates may also affect real estate values. If the Fund's real estate-related investments are concentrated in one geographic area or in one property type, the Fund will be particularly subject to the risks associated with that area or property type. Many issuers of real estate-related securities are highly leveraged, which increases the risk to holders of such securities. The value of the securities the Fund buys will not necessarily track the value of the underlying investments of the issuers of such securities. In addition, certain issuers of real estate-related securities may have developed or commenced development on properties and may develop additional properties in the future. Real estate development involves significant risks in addition to those involved in the ownership and operation of established properties. Real estate securities may have limited diversification and are, therefore, subject to risks inherent in operating and financing a limited number of projects. Real estate securities are also subject to heavy cash flow dependency and defaults by borrowers or tenants.

REIT Investment Risk - Investments in REITs involve unique risks. REITs may have limited financial resources, may trade less frequently and in limited volume, may engage in dilutive offerings of securities and may be more volatile than other securities. REIT issuers may also fail to maintain their exemptions from investment company registration or fail to qualify for the "dividends paid deduction" under the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code"), which allows REITs to reduce their corporate taxable income for dividends paid to their shareholders.

Representative Sampling Risk - Representative sampling is a method of indexing that involves investing in a representative sample of securities that collectively have a similar investment profile to the index and resemble the index in terms of risk factors and other key characteristics. A passively managed ETF may or may not hold every security in the index. When an ETF deviates from a full replication indexing strategy to utilize a representative sampling strategy, the ETF is subject to an increased risk of tracking error, in that the securities selected in the aggregate for the ETF may not have an investment profile similar to those of its index.

Shares of an ETF May Trade at Prices Other Than Net Asset Value - Shares of an ETF trade on exchanges at prices at, above or below their most recent net asset value. The per share net asset value of an ETF is calculated at the end of each business day and fluctuates with changes in the market value of the ETF's holdings since the most recent calculation. The trading prices of an ETF's shares fluctuate continuously throughout trading hours based on market supply and demand rather than net asset value. The trading prices of an ETF's shares may deviate significantly from net asset value during periods of market volatility. Any of these factors may lead to an ETF's shares trading at a premium or discount to net asset value. However, because shares can be created and redeemed in creation units, which are aggregated blocks of shares that authorized participants who have entered into agreements with the ETF's distributor can purchase or redeem directly from the ETF, at net asset value (unlike shares of many closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset values), large discounts or premiums to the net asset value of an ETF are not likely to be sustained over the long-term. While the creation/redemption feature is designed to make it likely that an ETF's shares normally trade on exchanges at prices close to the ETF's next calculated net asset value, exchange prices are not expected to correlate exactly with an ETF's net asset value due to timing reasons as well as market supply and demand factors. In addition, disruptions to creations and redemptions or the existence of extreme market volatility may result in trading prices that differ significantly from net asset value. If a shareholder purchases at a time when the market price is at a premium to the net asset value or sells at a time when the market price is at a discount to the net asset value, the shareholder may sustain losses. The use of cash creations and redemptions may also cause the ETFs' shares to trade in the market at greater bid-ask spreads or greater premiums or discounts to the ETFs' net asset value.

Small and Mid-Capitalization Company Risk - Companies with small or mid-size market capitalizations will normally have more limited product lines, markets and financial resources and will be dependent upon a more limited management group than larger capitalized companies. In addition, it is more difficult to get information on smaller companies, which tend to be less well known, have shorter operating histories, do not have significant ownership by large investors and are followed by relatively few securities analysts.

Tracking Error Risk - An Underlying Fund may be subject to tracking error, which is the divergence of an Underlying Fund's performance from that of its underlying index. Tracking error may occur because of differences between the securities and other instruments held in an Underlying Fund's portfolio and those included in its underlying index, pricing differences (including, as applicable, differences between a security's price at the local market close and an Underlying Fund's valuation of a security at the time of calculation of an Underlying Fund's net asset value), differences in transaction costs incurred by an Underlying Index, an Underlying Fund's holding of uninvested cash, differences in timing of the accrual of or the valuation of dividends or other distributions, interest, the requirements

to maintain pass-through tax treatment, portfolio transactions carried out to minimize the distribution of capital gains to shareholders, changes to an underlying index or the cost to an Underlying Fund of complying with various new or existing regulatory requirements, among other reasons. These risks may be heightened during times of increased market volatility or other unusual market conditions. In addition, tracking error may result because an Underlying Fund incurs fees and expenses, while its underlying index does not.

Treasury Obligations Risk - Direct obligations of the U.S. Treasury have historically involved little risk of loss of principal if held to maturity. However, due to fluctuations in interest rates, the market value of such securities may vary during the period shareholders own shares of the Fund. In addition, notwithstanding that U.S. Treasury obligations are backed by the full faith and credit of the United States, circumstances could arise that could prevent the timely payment of interest or principal, such as reaching the legislative "debt ceiling." Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.

U.S. Government Obligations Risk - Not all U.S. Government securities are backed by the full faith and credit of the United States. Obligations of certain agencies, authorities, instrumentalities and sponsored enterprises of the U.S. Government are backed by the full faith and credit of the United States (e.g., the Government National Mortgage Association); other obligations are backed by the right of the issuer to borrow from the U.S. Treasury (e.g., the Federal Home Loan Banks) and others are supported by the discretionary authority of the U.S. Government to purchase an agency's obligations. Still others are backed only by the credit of the agency, authority, instrumentality or sponsored enterprise issuing the obligation. No assurance can be given that the U.S. Government would provide financial support to any of these entities if it is not obligated to do so by law. In addition, circumstances could arise that could prevent the timely payment of interest or principal on U.S. Government obligations, such as reaching the legislative "debt ceiling." Such non-payment could result in losses to the Fund and substantial negative consequences for the U.S. economy and the global financial system.

Valuation Risk - The price the Fund could receive upon the sale of any particular portfolio investment may differ from the Fund's valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation methodology or a price provided by an independent pricing service. As a result, the price received upon the sale of an investment may be less than the value ascribed by the Fund, and the Fund could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. Pricing services that value fixed-income securities generally utilize a range of market-based and security-specific inputs and assumptions, as well as considerations about general market conditions, to establish a price. Pricing services generally value fixed-income securities assuming orderly transactions of an institutional round lot size, but may be held or transactions may be conducted in such securities in smaller, odd lot sizes. Odd lots may trade at lower prices than institutional round lots. The Fund's ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.

Portfolio Manager

Chris Chung, CFA

Lisa O'Connor, CFA

Greg Savage, CFA

Paul Whitehead

$1,000 for all accounts except:

• $50, if establishing an Automatic Investment Plan.

• There is no investment minimum for employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs).

• There is no investment minimum for certain fee-based programs.

There is no minimum initial investment for:

• Employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs or SARSEPs), state sponsored 529 college savings plans, collective trust funds, investment companies or other pooled investment vehicles, unaffiliated thrifts and unaffiliated banks and trust companies, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund's distributor to purchase such shares.

• Clients of Financial Intermediaries that: (i) charge such clients a fee for advisory, investment consulting, or similar services or (ii) have entered into an agreement with the Fund's distributor to offer Institutional Shares through a no-load program or investment platform.

• Clients investing through a self-directed IRA brokerage account program sponsored by a retirement plan recordkeeper, provided that such program offers only mutual fund options and that the program maintains an account with the Fund on an omnibus basis.

$2 million for individuals and "Institutional Investors," which include, but are not limited to, endowments, foundations, family offices, local, city, and state governmental institutions, corporations and insurance company separate accounts who may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund's distributor to purchase such shares.

$1,000 for:

Clients investing through Financial Intermediaries that offer such shares on a platform that charges a transaction based sales commission outside of the Fund.

• Tax-qualified accounts for insurance agents that are registered representatives of an insurance company's broker-dealer that has entered into an agreement with the Fund's distributor to offer Institutional Shares, and the family members of such persons.