BLACKROCK INDEX FUNDS, INC. (Form: 485BPOS, Received: 04/30/2018 17:46:04)

As filed with the Securities and Exchange Commission on April 30, 2018

Securities Act File No. 333-15265

Investment Company Act File No. 811-7899

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

☒

Pre-Effective Amendment No.

□

Post-Effective Amendment No. 38

☒

and/or

REGISTRATION STATEMENT UNDER THE

INVESTMENT COMPANY ACT OF 1940

☒

Amendment No. 39

☒

(Check appropriate box or boxes)

BlackRock Index Funds, Inc.

(Exact Name of Registrant as Specified in Charter)

100 Bellevue Parkway, Wilmington, Delaware 19809
United States of America

(Address of Principal Executive Offices)

Registrant’s Telephone Number, including Area Code: (800) 441-7762

John M. Perlowski

BlackRock Index Funds, Inc.
55 East 52nd Street

New York, New York 10055
United States of America

(Name and Address of Agent for Service)

Copies to:

Counsel for the Fund:
John A. MacKinnon, Esq. Sidley Austin LLP 787 Seventh Avenue New York, New York 10019-6018	Benjamin Archibald, Esq. BlackRock Advisors, LLC 55 East 52nd Street New York, New York 10055

It is proposed that this filing will become effective (check appropriate box)

☒ Immediately upon filing pursuant to paragraph (b)

□ On (date) pursuant to paragraph (b)

□ 60 days after filing pursuant to paragraph (a)(1)

□ On (date) pursuant to paragraph (a)(1)

□ 75 days after filing pursuant to paragraph (a)(2)

□ On (date) pursuant to paragraph (a)(2) of Rule 485

If appropriate, check the following box:

□ This post-effective amendment designates a new effective date for a previously filed post-effective amendment.
Title of Securities Being Registered: Shares of Common Stock, par value $0.0001 per share.

Quantitative Master Series LLC has also executed this Registration Statement.

APRIL 30, 2018

Prospectus

BlackRock Index Funds, Inc. | Investor and Institutional Shares

►	iShares Russell 2000 Small-Cap Index Fund

Investor A: MDSKX • Institutional: MASKX

►	iShares MSCI EAFE International Index Fund

Investor A: MDIIX • Institutional: MAIIX

This 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 has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

Not FDIC Insured • May Lose Value • No Bank Guarantee

Table of Contents

Fund Overview	Key facts and details about the Funds listed in this prospectus, including investment objectives, principal investment strategies, principal risk factors, fee and expense information and historical performance information
	Key Facts About iShares Russell 2000 Small-Cap Index Fund	3
	Key Facts About iShares MSCI EAFE International Index Fund	8

Details About the Funds	Information about how each Fund invests, including investment objectives, investment processes, principal strategies and risk factors
	How Each Fund Invests	13
	Investment Risks	16

Account Information	Information about account services, sales charges and waivers, shareholder transactions, and distribution and other payments
	How to Choose the Share Class that Best Suits Your Needs	23
	Details About the Share Classes	24
	Distribution and Shareholder Servicing Payments	25
	How to Buy, Sell, Exchange and Transfer Shares	26
	Account Services and Privileges	32
	Funds’ Rights	33
	Participation in Fee-Based Programs	33
	Short-Term Trading Policy	33
	Master/Feeder Structure	34

Management of the Funds	Information about BlackRock and the Portfolio Managers
	BlackRock	36
	Portfolio Manager Information	38
	Conflicts of Interest	39
	Valuation of Fund Investments	40
	Dividends, Distributions and Taxes	41

Financial Highlights	Financial Performance of the Funds	42

General Information	Shareholder Documents	46
	Certain Fund Policies	46
	Statement of Additional Information	47

Glossary	Glossary of Investment Terms	48

For More Information	Funds and Service Providers	Inside Back Cover
	Additional Information	Back Cover

Table of Contents

Fund Overview

Key Facts About iShares Russell 2000 Small-Cap Index Fund

Investment Objective

The investment objective of iShares Russell 2000 Small-Cap Index Fund (formerly known as BlackRock Small Cap Index Fund) (“Russell 2000 Small-Cap Index Fund” or the “Fund”), a series of BlackRock Index Funds, Inc. (the “Corporation”), is to match the performance of the Russell 2000 ^® Index (the “Russell 2000” or the “Underlying Index”) as closely as possible before the deduction of Fund expenses.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of Russell 2000 Small-Cap Index Fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) ¹		Investor A Shares		Institutional Shares
Management Fee ^1,2		0.01%		0.01%
Distribution and/or Service (12b-1) Fees		0.25%		None
Other Expenses		0.19%		0.17%
Administration Fees	0.04%		0.04%
Miscellaneous Other Expenses	0.15%		0.13%
Total Annual Fund Operating Expenses		0.45%		0.18%
Fee Waivers and/or Expense Reimbursements ^2,3		(0.08)%		(0.06)%
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements ^2,3		0.37%		0.12%

The fees and expenses shown in the table and the example that follows include both the expenses of Russell 2000 Small-Cap Index Fund and Russell 2000 Small-Cap Index Fund’s share of the allocated expenses of Master Small Cap Index Series (the “Series”), a series of Quantitative Master Series LLC (the “Master LLC”). Management fees are paid by the Series.

As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 36, BlackRock Advisors, LLC (“BlackRock”) has contractually agreed to waive the management fee with respect to any portion of the Series’ assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series.

As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 36, BlackRock has contractually agreed to waive and/or reimburse fees and/or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of Russell 2000 Small-Cap Index Fund (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) as a percentage of average daily net assets to 0.37% (for Investor A Shares) and 0.12% (for Institutional Shares) through April 30, 2019. In addition to the contractual waiver with respect to the Fund, BlackRock 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 of the Series (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Series expenses) to 0.07% of average daily net assets through April 30, 2019. These contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or of the Master LLC, as applicable, or by a vote of a majority of the outstanding voting securities of the Fund or the Series, as applicable.

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
Investor A Shares	$38	$136	$244	$559
Institutional Shares	$12	$ 52	$ 95	$224

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Portfolio Turnover:

The Series 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 Russell 2000 Small-Cap Index Fund’s performance. During the most recent fiscal year, the Series’ portfolio turnover rate was 30% of the average value of its portfolio.

Principal Investment Strategies of the Fund

Russell 2000 Small-Cap Index Fund employs a “passive” management approach, attempting to invest in a portfolio of assets whose performance is expected to match approximately the performance of the Russell 2000. The Fund will be substantially invested in securities in the Russell 2000, and will invest, under normal circumstances, at least 80% of its assets in securities or other financial instruments that are components of or have economic characteristics similar to the securities included in the Russell 2000. The Fund may change its target index if Fund management believes a different index would better enable the Fund to match the performance of the market segment represented by the current index.

The Fund may invest in a statistically selected sample of stocks included in the Russell 2000 and in derivative instruments linked to the Russell 2000. The Fund may not invest in all of the common stocks in the Russell 2000, or in the same weightings as in the Russell 2000. The Fund chooses investments so that the market capitalizations, industry weightings and other fundamental characteristics of the stocks and derivative instruments chosen are similar to the Russell 2000 as a whole.

The Fund is a “feeder” fund that invests all of its assets in the Series, a series of the Master LLC, which has the same investment objective and strategies as the Fund. All investments are made at the Series level. This structure is sometimes called a “master/feeder” structure. The Fund’s investment results will correspond directly to the investment results of the Series. For simplicity, this prospectus uses the name of the Fund or the term “Fund” (as applicable) to include the Series.

Principal Risks of Investing in the Fund

Risk is inherent in all investing. The value of your investment in Russell 2000 Small-Cap Index 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 the principal risks of investing in the Fund.

■	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.
■	Index Fund Risk — An index fund has operating and other expenses while an index does not. As a result, while the Fund will attempt to track the Russell 2000 as closely as possible, it will tend to underperform the index to some degree over time. If an index fund is properly correlated to its stated index, the fund will perform poorly when the index performs poorly.

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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, index computations and/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.

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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.

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Small Cap Securities Risk — Small cap companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a more limited management group than larger capitalized companies.

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Performance Information

The information shows 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 Russell 2000. 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. The table includes all applicable fees. If BlackRock 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 www.blackrock.com or can be obtained by phone at (800) 882-0052.

Investor A Shares

ANNUAL TOTAL RETURNS

Russell 2000 Small-Cap Index Fund
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 20.61% (quarter ended June 30, 2009) and the lowest return for a quarter was -26.31% (quarter ended December 31, 2008).

As of 12/31/17 Average Annual Total Returns	1 Year	5 Years	10 Years
iShares Russell 2000 Small-Cap Index Fund — Investor A Shares
Return Before Taxes	14.35%	13.86%	8.31%
Return After Taxes on Distributions	13.37%	12.52%	7.23%
Return After Taxes on Distributions and Sale of Fund Shares	8.58%	10.80%	6.40%
iShares Russell 2000 Small-Cap Index Fund — Institutional Shares
Return Before Taxes	14.55%	14.14%	8.57%
Russell 2000 ^® Index (Reflects no deduction for fees, expenses or taxes)	14.65%	14.12%	8.71%

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. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Institutional Shares will vary.

Investment Manager

Russell 2000 Small-Cap Index Fund’s investment manager is BlackRock Advisors, LLC (previously defined as “BlackRock”). Russell 2000 Small-Cap Index Fund’s sub-adviser is BlackRock Fund Advisors (the “Sub-Adviser”). Where applicable, “BlackRock” refers also to the Sub-Adviser.

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Portfolio Managers

Name	Portfolio Manager of the Series Since	Title
Alan Mason	2014	Managing Director of BlackRock, Inc.
Greg Savage, CFA	2012	Managing Director of BlackRock, Inc.
Jennifer Hsui, CFA	2016	Managing Director of BlackRock, Inc.
Creighton Jue, CFA	2016	Managing Director of BlackRock, Inc.
Rachel Aguirre	2016	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 is open. To purchase or sell shares you should contact your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock, The PNC Financial Services Group, Inc. 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) 441-7762, by mail (c/o BlackRock Funds, P.O. Box 9819, Providence, Rhode Island 02940-8019), or by the Internet at www.blackrock.com. The Fund’s initial and subsequent investment minimums generally are as follows, although the Fund may reduce or waive the minimums in some cases:

	Investor A Shares	Institutional Shares
Minimum Initial Investment	$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. • Investors of Financial Intermediaries that: (i) charge such investors 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. $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.
Minimum Additional Investment	$50 for all accounts (with the exception of certain employer-sponsored retirement plans which may have a lower minimum).	No subsequent minimum.

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Tax Information

The Fund’s dividends and distributions may be subject to U.S. 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 qualified tax-exempt plan described in section 401(a) of the Internal Revenue Code of 1986, as amended, in which case you may be subject to U.S. federal income tax when distributions are received 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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Fund Overview

Key Facts About iShares MSCI EAFE International Index Fund

Investment Objective

The investment objective of iShares MSCI EAFE International Index Fund (formerly known as BlackRock International Index Fund) (“MSCI EAFE International Index Fund” or the “Fund”), a series of BlackRock Index Funds, Inc. (the “Corporation”), is to match the performance of the MSCI EAFE Index (Europe, Australasia, Far East) (the “MSCI EAFE Index” or the “Underlying Index”) in U.S. dollars with net dividends as closely as possible before the deduction of Fund expenses.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of MSCI EAFE International Index Fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)	Investor A Shares	Institutional Shares
Management Fee ¹	0.01%	0.01%
Distribution and/or Service (12b-1) Fees	0.25%	None
Other Expenses	0.10%	0.08%
Total Annual Fund Operating Expenses	0.36%	0.09%
Fee Waivers and/or Expense Reimbursements ^1,2	—	—
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements ^1,2	0.36%	0.09%

As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 36, BlackRock Advisors, LLC (“BlackRock”) has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the Fund.

Example:

	1 Year	3 Years	5 Years	10 Years
Investor A Shares	$37	$116	$202	$456
Institutional Shares	$ 9	$ 29	$ 51	$115

Portfolio Turnover:

MSCI EAFE International Index 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, MSCI EAFE International Index Fund’s portfolio turnover rate was 23% of the average value of its portfolio.

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Principal Investment Strategies of the Fund

MSCI EAFE International Index Fund employs a “passive” management approach, attempting to invest in a portfolio of assets whose performance is expected to match approximately the performance of the MSCI EAFE Index. The Fund will be substantially invested in securities in the MSCI EAFE Index, and will invest, under normal circumstances, at least 80% of its assets in securities or other financial instruments that are components of or have economic characteristics similar to the securities included in the MSCI EAFE Index. The Fund may change its target index if Fund management believes a different index would better enable the Fund to match the performance of the market segment represented by the current index.

MSCI EAFE International Index Fund invests in a statistically selected sample of equity securities included in the MSCI EAFE Index and in derivative instruments linked to the MSCI EAFE Index. Equity securities include common stock, preferred stock and securities or other instruments whose price is linked to the value of common stock. The Fund will, under normal circumstances, invest in all of the countries represented in the MSCI EAFE Index. The Fund may not, however, invest in all of the companies within a country represented in the MSCI EAFE Index, or in the same weightings as in the MSCI EAFE Index.

Principal Risks of Investing in the Fund

Risk is inherent in all investing. The value of your investment in MSCI EAFE International Index 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 the principal risks of investing in the Fund.

■	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.
■	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.
■	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. These events may spread to other countries in Europe. These events may affect the value and liquidity of certain of the Fund’s investments.

■

Index Fund Risk — An index fund has operating and other expenses while an index does not. As a result, while the Fund will attempt to track the MSCI EAFE Index as closely as possible, it will tend to underperform the index to some degree over time. If an index fund is properly correlated to its stated index, the fund will perform poorly when the index performs poorly.

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Performance Information

The information shows 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 MSCI EAFE 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. The table includes all applicable fees. If BlackRock 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 www.blackrock.com or can be obtained by phone at (800) 882-0052.

Investor A Shares

ANNUAL TOTAL RETURNS

MSCI EAFE International Index Fund
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 25.14% (quarter ended June 30, 2009) and the lowest return for a quarter was -20.18% (quarter ended September 30, 2011).

As of 12/31/17 Average Annual Total Returns	1 Year	5 Years	10 Years
iShares MSCI EAFE International Index Fund — Investor A Shares
Return Before Taxes	24.84%	7.12%	1.39%
Return After Taxes on Distributions	24.24%	6.78%	0.71%
Return After Taxes on Distributions and Sale of Fund Shares	14.64%	5.67%	0.85%
iShares MSCI EAFE International Index Fund — Institutional Shares
Return Before Taxes	25.24%	7.41%	1.66%
MSCI EAFE Index (Europe, Australasia, Far East) (Reflects no deduction for fees, expenses or taxes)	25.03%	7.90%	1.94%

Investment Manager

MSCI EAFE International Index Fund’s investment manager is BlackRock Advisors, LLC (previously defined as “BlackRock”). MSCI EAFE International Index Fund’s sub-adviser is BlackRock Fund Advisors (the “Sub-Adviser”). Where applicable, “BlackRock” refers also to the Sub-Adviser.

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Portfolio Managers

Name	Portfolio Manager of the Fund Since	Title
Alan Mason	2014	Managing Director of BlackRock, Inc.
Greg Savage, CFA	2012	Managing Director of BlackRock, Inc.
Jennifer Hsui, CFA	2016	Managing Director of BlackRock, Inc.
Creighton Jue, CFA	2016	Managing Director of BlackRock, Inc.
Rachel Aguirre	2016	Managing Director of BlackRock, Inc.

Purchase and Sale of Fund Shares

	Investor A Shares	Institutional Shares
Minimum Initial Investment	$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. • Investors of Financial Intermediaries that: (i) charge such investors 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. $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.
Minimum Additional Investment	$50 for all accounts (with the exception of certain employer-sponsored retirement plans which may have a lower minimum).	No subsequent minimum.

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Tax Information

Payments to Broker/Dealers and Other Financial Intermediaries

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Details About the Funds

Included in this prospectus are sections that tell you about buying and selling shares, management information, shareholder features of iShares Russell 2000 Small-Cap Index Fund (formerly known as BlackRock Small Cap Index Fund) (“Russell 2000 Small-Cap Index Fund”) and iShares MSCI EAFE International Index Fund (formerly known as BlackRock International Index Fund) (“MSCI EAFE International Index Fund”) (each a “Fund” and collectively the “Funds”), each a series of BlackRock Index Funds, Inc. (the “Corporation”), and your rights as a shareholder. Russell 2000 Small-Cap Index Fund is a “feeder” fund that invests all of its assets in Master Small Cap Index Series (the “Series”) of Quantitative Master Series LLC (the “Master LLC”), a mutual fund that has the same objective and strategies as Russell 2000 Small-Cap Index Fund. All of Russell 2000 Small-Cap Index Fund’s investments will be made at the Master LLC level. This structure is sometimes called a “master/feeder” structure. Russell 2000 Small-Cap Index Fund’s investment results will correspond directly to the investment results of the Series. For simplicity, this prospectus uses the name “Russell 2000 Small-Cap Index Fund” or the term “Fund,” if applicable, to include the Series.

How Each Fund Invests

Investment Process

The Funds will not attempt to buy or sell securities based on Fund management’s economic, financial or market analysis, but will instead employ a “passive” investment approach. This means that Fund management will attempt to invest in a portfolio of assets whose performance is expected to match approximately the performance of the respective index before deduction of Fund expenses. A Fund will buy or sell securities only when Fund management believes it is necessary to do so in order to match the performance of the applicable index. Accordingly, it is anticipated that a Fund’s portfolio turnover rate and trading costs will be lower than those of an “actively” managed fund. However, the Funds have operating and other expenses, while an index does not. Therefore, each Fund will tend to underperform its target index to some degree over time.

Russell 2000 Small-Cap Index Fund

Investment Objective

The investment objective of Russell 2000 Small-Cap Index Fund is to match the performance of the Russell 2000 ^® Index (the “Russell 2000” or the “Underlying Index”) as closely as possible before the deduction of Fund expenses.

The Russell 2000 is composed of the common stocks of approximately the 1,001st through the 3,000th largest U.S. companies by market capitalization, as determined by Russell Investments (“Russell” or the “Index Provider”). The stocks represented in the Russell 2000 are issued by small capitalization U.S. companies in a wide range of businesses. The Russell 2000 is a market-weighted index, which means that the largest stocks represented in the index have the most effect on the index’s performance. The Russell 2000 is generally considered broadly representative of the performance of publicly traded U.S. smaller-capitalization stocks. Russell’s selection of a stock for the Russell 2000 does not mean that Russell believes the stock to be an attractive investment. Russell updates the Russell 2000 once each year, at which time there may be substantial changes in the composition of the index (and consequently, significant turnover in the Fund). Stocks of companies that merge, are acquired or otherwise cease to exist during the year are not replaced in the index.

Principal Investment Strategies

Russell 2000 Small-Cap Index Fund will be substantially invested in securities in the Russell 2000, and will invest, under normal circumstances, at least 80% of its assets in securities or other financial instruments that are components of or have economic characteristics similar to the securities included in the Russell 2000. This is a non-fundamental policy of the Fund and may not be changed without 60 days’ prior notice to shareholders. The Fund may change its target index if Fund management believes a different index would better enable the Fund to match the performance of the market segment represented by the Russell 2000 and, accordingly, the investment objective of the Fund may be changed without shareholder approval.

The Fund may not invest in all of the common stocks in the Russell 2000, or in the same weightings as in the Russell 2000. Instead, the Fund may invest in a statistically selected sample of the stocks included in the Russell 2000 and in derivative instruments linked to the Russell 2000. The Fund will choose investments so that the market

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capitalizations, industry weightings and other fundamental characteristics of the stocks and derivative instruments in its portfolio are similar to the Russell 2000 as a whole.

The past performance of the Underlying Index is not a guide to future performance. BlackRock Advisors, LLC (“BlackRock”) does not guarantee the accuracy or the completeness of the Underlying Index or any data included therein and BlackRock shall have no liability for any errors, omissions or interruptions therein. BlackRock makes no warranty, express or implied, to the owners of shares of the Fund or to any other person or entity, as to results to be obtained by the Fund from the use of the Underlying Index or any data included therein. Without limiting any of the foregoing, in no event shall BlackRock have any liability for any special, punitive, direct, indirect or consequential damages (including lost profits), even if notified of the possibility of such damages.

ABOUT THE PORTFOLIO MANAGEMENT TEAM OF MASTER SMALL CAP INDEX SERIES

The Series is managed by a team of financial professionals. Alan Mason, Greg Savage, CFA, Jennifer Hsui, CFA, Creighton Jue, CFA, and Rachel Aguirre are the portfolio managers of the Series and are jointly and primarily responsible for the day-to-day management of the Series. Please see “Management of the Funds — Portfolio Manager Information” for additional information about the portfolio management team.

MSCI EAFE International Index Fund

Investment Objective

The investment objective of MSCI EAFE International Index Fund is to match the performance of the MSCI EAFE Index (Europe, Australasia, Far East) (the “MSCI EAFE Index” or the “Underlying Index”) in U.S. dollars with net dividends as closely as possible before the deduction of Fund expenses.

The MSCI EAFE Index is composed of equity securities of approximately 1,000 companies from various industrial sectors whose primary trading markets are located outside the United States. Equity securities include common stock, preferred stock and securities or other instruments whose price is linked to the value of common stock. Companies included in the MSCI EAFE Index are selected from among the larger capitalization companies in these markets. The countries currently included in the MSCI EAFE Index are Australia, Austria, Belgium, Denmark, Finland, France, Germany, Hong Kong, Ireland, Israel, Italy, Japan, the Netherlands, New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland and the United Kingdom. The weighting of the MSCI EAFE Index among these countries is based upon each country’s relative market capitalization and not its gross domestic product, which means that the index contains more companies from countries with larger capital markets (like Japan and the United Kingdom) and these countries have the most effect on the index’s performance. The stocks in the MSCI EAFE Index are chosen by MSCI Inc. (“MSCI” or the “Index Provider”). MSCI chooses stocks for inclusion in the MSCI EAFE Index based on market capitalization, trading activity and the overall mix of industries represented in the index, among other factors. The MSCI EAFE Index is generally considered broadly representative of the performance of stocks traded in the developed international markets. MSCI’s selection of a stock for the MSCI EAFE Index does not mean that MSCI believes the stock to be an attractive investment.

Principal Investment Strategies

MSCI EAFE International Index Fund will be substantially invested in securities in the MSCI EAFE Index, and will invest, under normal circumstances, at least 80% of its assets in securities or other financial instruments that are components of or have economic characteristics similar to the securities included in the MSCI EAFE Index. This is a non-fundamental policy of the Fund and may not be changed without 60 days’ prior notice to shareholders. The Fund may change its target index if Fund management believes a different index would better enable the Fund to match the performance of the market segment represented by the MSCI EAFE Index and, accordingly, the investment objective of the Fund may be changed without shareholder approval.

The Fund will, under normal circumstances, invest in all of the countries represented in the MSCI EAFE Index. The Fund may not, however, invest in all of the companies within a country represented in the MSCI EAFE Index, or in the same weightings as in the MSCI EAFE Index. Instead, the Fund may invest in a statistically selected sample of equity securities included in the MSCI EAFE Index and in derivative instruments correlated with components of the MSCI EAFE Index as a whole.

The past performance of the Underlying Index is not a guide to future performance. BlackRock does not guarantee the accuracy or the completeness of the Underlying Index or any data included therein and BlackRock shall have no liability for any errors, omissions or interruptions therein. BlackRock makes no warranty, express or implied, to the owners of shares of the Fund or to any other person or entity, as to results to be obtained by the Fund from the use of the

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Underlying Index or any data included therein. Without limiting any of the foregoing, in no event shall BlackRock have any liability for any special, punitive, direct, indirect or consequential damages (including lost profits), even if notified of the possibility of such damages.

ABOUT THE PORTFOLIO MANAGEMENT TEAM OF MSCI EAFE INTERNATIONAL INDEX FUND

The Fund is managed by a team of financial professionals. Alan Mason, Greg Savage, CFA, Jennifer Hsui, CFA, Creighton Jue, CFA, and Rachel Aguirre are the portfolio managers of the Fund and are jointly and primarily responsible for the day-to-day management of the Fund. Please see “Management of the Funds — Portfolio Manager Information” for additional information about the portfolio management team.

Other Strategies Applicable to the Funds

In addition to the principal strategies discussed above, each Fund may also invest or engage in the following investments/strategies:

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Borrowing — Each Fund may borrow for temporary or emergency purposes, including to meet redemptions, for the payment of dividends, for share repurchases or for the clearance of transactions, subject to the limits set forth under the Investment Company Act, the rules and regulations thereunder and any applicable exemptive relief.

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Depositary Receipts — Each Fund may invest in securities of foreign issuers in the form of depositary receipts or other securities that are convertible into securities of foreign issuers. American Depositary Receipts are receipts typically issued by an American bank or trust company that evidence underlying securities issued by a foreign corporation. European Depositary Receipts (issued in Europe) and Global Depositary Receipts (issued throughout the world) each evidence a similar ownership arrangement. Each Fund may invest in unsponsored depositary receipts.

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Derivatives — Each Fund may invest in derivative instruments. Russell 2000 Small-Cap Index Fund may at times invest a significant portion of its assets in futures contracts and other derivatives linked to the performance of the Russell 2000, and MSCI EAFE International Index Fund may at times invest a significant portion of its assets in futures contracts and other derivatives correlated with market indices or countries within the MSCI EAFE Index. Derivatives allow a Fund to increase or decrease its exposure to the companies included in the Russell 2000 (for Russell 2000 Small-Cap Index Fund) and to international stocks (for MSCI EAFE International Index Fund) quickly and at less cost than buying or selling stocks. The Funds will invest in futures and other derivative instruments in order to gain market exposure quickly in the event of subscriptions, to maintain liquidity in the event of redemptions and to keep trading costs low. In connection with the use of derivative instruments, the Funds may enter into short sales in order to adjust the weightings of particular securities represented in a derivative to more accurately reflect the securities’ weightings in the target index. The Funds may use derivatives for hedging purposes, including anticipatory hedges, and to seek to enhance returns.

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Illiquid/Restricted Securities — Each Fund may invest up to 15% of its net assets in illiquid securities that it cannot sell within seven days at approximately current value. Each Fund may also invest in restricted securities, which are securities that cannot be offered for public resale unless registered under the applicable securities laws or that have a contractual restriction that prohibits or limits their resale (i.e., Rule 144A securities). They may include private placement securities that have not been registered under the applicable securities laws. Restricted securities may not be listed on an exchange and may have no active trading market and therefore may be considered to be illiquid. Rule 144A securities are restricted securities that can be resold to qualified institutional buyers but not to the general public and may be considered to be liquid securities.

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Investment Companies — Each Fund has the ability to invest in other investment companies, such as exchange-traded funds (“ETFs”), unit investment trusts, and open-end and closed-end funds. Each Fund may invest in affiliated investment companies, including affiliated money market funds and affiliated ETFs.

■	“New Issues” (Russell 2000 Small-Cap Index Fund) — The Fund has the ability to invest in “new issues.” “New issues” are initial public offerings (“IPOs”) of equity securities.

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Real Estate Investment Trusts (“REITs”) — Each Fund may invest in REITs. REITs are companies that own interests in real estate or in real estate-related loans or other interests, and have revenue primarily consisting of rent derived from owned, income producing real estate properties and capital gains from the sale of such properties. REITs can generally be classified as equity REITs, mortgage REITs and hybrid REITs. Equity REITs invest the majority of their assets directly in real property and derive their income primarily from rents. Equity REITs can also realize capital gains by selling properties that have appreciated in value. Mortgage REITs invest the majority of their assets in real estate mortgages and derive their income primarily from interest payments. Hybrid REITs

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combine the characteristics of both equity REITs and mortgage REITs. REITs are not taxed on income distributed to shareholders provided they comply with the requirements of the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”).

■	Repurchase Agreements — Each Fund may enter into certain types of repurchase agreements. Under a repurchase agreement, the seller agrees to repurchase a security at a mutually agreed-upon time and price.
■	Securities Lending — Each Fund may lend securities with a value up to 33 ¹ ⁄ 3 % of its total assets to financial institutions that provide cash or securities issued or guaranteed by the U.S. Government as collateral.
■	Short-Term Money Market Instruments — Each Fund may invest in short-term money market instruments as cash reserves to maintain liquidity. These instruments may include obligations of the U.S. Government, its agencies or instrumentalities, highly rated bonds or comparable unrated bonds, commercial paper, bank obligations, repurchase agreements and commingled short-term liquidity funds. To the extent a Fund invests in short-term money market instruments, it will generally also invest in futures or other derivatives in order to maintain full exposure to the index at all times.

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When-Issued and Delayed Delivery Securities and Forward Commitments (Russell 2000 Small-Cap Index Fund) — The purchase or sale of securities on a when-issued basis or on a delayed delivery basis or through a forward commitment involves the purchase or sale of securities by the Fund at an established price with payment and delivery taking place in the future. The Fund enters into these transactions to obtain what is considered an advantageous price to the Fund at the time of entering into the transaction.

Investment Risks

This section contains a discussion of the general risks of investing in the Funds. The “Investment Objectives and Policies” section in the Statement of Additional Information (the “SAI”) also includes more information about the Fund, its investments and the related risks. As with any fund, there can be no guarantee that the Fund will meet its investment objective or that the Fund’s performance will be positive for any period of time. An investment in the Fund is not a deposit in any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or by any bank or governmental agency.

Principal Risks of Investing in the Funds

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Equity Securities Risk — Common and preferred stocks represent equity ownership in a company. Stock markets are volatile. The price of equity securities will fluctuate and can decline and reduce the value of a portfolio investing in equities. The value of equity securities purchased by the Fund could decline if the financial condition of the companies the Fund invests in declines or if overall market and economic conditions deteriorate. The value of equity securities may also decline due to factors that affect a particular industry or industries, such as labor shortages or an increase in production costs and competitive conditions within an industry. In addition, the value may decline due to general market conditions that are not specifically related to a company or industry, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or generally adverse investor sentiment.

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Foreign Securities Risk (MSCI EAFE International Index Fund) — Securities traded in foreign markets have often (though not always) performed differently from securities traded in the United States. However, such investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. In particular, the Fund is subject to the risk that because there may be fewer investors on foreign exchanges and a smaller number of securities traded each day, it may be more difficult for the Fund to buy and sell securities on those exchanges. In addition, prices of foreign securities may go up and down more than prices of securities traded in the United States.

Certain Risks of Holding Fund Assets Outside the United States — The Fund generally holds its foreign securities and cash in foreign banks and securities depositories. Some foreign banks and securities depositories may be recently organized or new to the foreign custody business. In addition, there may be limited or no regulatory oversight of their operations. Also, the laws of certain countries limit the Fund’s ability to recover its assets if a foreign bank, depository or issuer of a security, or any of their agents, goes bankrupt. In addition, it is often more expensive for the Fund to buy, sell and hold securities in certain foreign markets than in the United States. The increased expense of investing in foreign markets reduces the amount the Fund can earn on its investments and typically results in a higher operating expense ratio for the Fund than for investment companies invested only in the United States.

Currency Risk — Securities and other instruments in which the Fund invests may be denominated or quoted in currencies other than the U.S. dollar. For this reason, changes in foreign currency exchange rates can affect the value of the Fund’s portfolio.

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	Generally, when the U.S. dollar rises in value against a foreign currency, a security denominated in that currency loses value because the currency is worth fewer U.S. dollars. Conversely, when the U.S. dollar decreases in value against a foreign currency, a security denominated in that currency gains value because the currency is worth more U.S. dollars. This risk, generally known as “currency risk,” means that a strong U.S. dollar will reduce returns for U.S. investors while a weak U.S. dollar will increase those returns.
	Foreign Economy Risk — 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. Certain foreign economies may rely heavily on particular industries or foreign capital and are more vulnerable to diplomatic developments, the imposition of economic sanctions against a particular country or countries, changes in international trading patterns, trade barriers and other protectionist or retaliatory measures. Investments in foreign markets may also be adversely affected by governmental actions such as the imposition of capital controls, nationalization of companies or industries, expropriation of assets or the imposition of punitive taxes. In addition, the governments of certain countries may prohibit or impose substantial restrictions on foreign investments in their capital markets or in certain industries. Any of these actions could severely affect securities prices or impair the Fund’s ability to purchase or sell foreign securities or transfer the Fund’s assets or income back into the United States, or otherwise adversely affect the Fund’s operations.
	Other potential foreign market risks include foreign exchange controls, difficulties in pricing securities, defaults on foreign government securities, difficulties in enforcing legal judgments in foreign courts and political and social instability. Diplomatic and political developments, including rapid and adverse political changes, social instability, regional conflicts, terrorism and war, could affect the economies, industries and securities and currency markets, and the value of the Fund’s investments, in non-U.S. countries. These factors are extremely difficult, if not impossible, to predict and take into account with respect to the Fund’s investments.
	Governmental Supervision and Regulation/Accounting Standards — Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as such regulations exist in the United States. They also may not have laws to protect investors that are comparable to U.S. securities laws. For example, some foreign countries may have no laws or rules against insider trading. Insider trading occurs when a person buys or sells a company’s securities based on material non-public information about that company. In addition, some countries may have legal systems that may make it difficult for the Fund to vote proxies, exercise shareholder rights, and pursue legal remedies with respect to its foreign investments. Accounting standards in other countries are not necessarily the same as in the United States. If the accounting standards in another country do not require as much detail as U.S. accounting standards, it may be harder for Fund management to completely and accurately determine a company’s financial condition.
	Settlement Risk — Settlement and clearance procedures in certain foreign markets differ significantly from those in the United States. Foreign settlement and clearance procedures and trade regulations also may involve certain risks (such as delays in payment for or delivery of securities) not typically associated with the settlement of U.S. investments.
	At times, settlements in certain foreign countries have not kept pace with the number of securities transactions. These problems may make it difficult for the Fund to carry out transactions. If the Fund cannot settle or is delayed in settling a purchase of securities, it may miss attractive investment opportunities and certain of its assets may be uninvested with no return earned thereon for some period. If the Fund cannot settle or is delayed in settling a sale of securities, it may lose money if the value of the security then declines or, if it has contracted to sell the security to another party, the Fund could be liable for any losses incurred.
	European Economic Risk — 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. These events may spread to other countries in Europe. These events may affect the value and liquidity of certain of the Fund’s investments.
	Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. In addition, the United Kingdom has voted to withdraw from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching.
■	Index Fund Risk — An index fund has operating and other expenses while an index does not. As a result, while the Fund will attempt to track the applicable index as closely as possible, it will tend to underperform the index to some

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degree over time. If an index fund is properly correlated to its stated index, the fund will perform poorly when the index performs poorly.

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Index-Related Risk — The Fund seeks to achieve a return that corresponds generally to the price and yield performance, before fees and expenses, of the Underlying Index as published by the Index Provider. There is no assurance that the Index Provider or any agents that may act on its behalf will compile the Underlying Index accurately, or that the Underlying Index will be determined, composed or calculated accurately. While the Index Provider provides descriptions of what the Underlying Index is designed to achieve, neither the Index Provider nor its agents provide any warranty or accept any liability in relation to the quality, accuracy or completeness of the Underlying Index or its related data, and they do not guarantee that the Underlying Index will be in line with the Index Provider’s methodology. BlackRock’s mandate as described in this prospectus is to manage the Fund consistently with the Underlying Index provided by the Index Provider to BlackRock. BlackRock does not provide any warranty or guarantee against the Index Provider’s or any agent’s errors. Errors in respect of the quality, accuracy and completeness of the data used to compile the Underlying Index 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, particularly where the indices are less commonly used as benchmarks by funds or managers. Therefore, gains, losses or costs associated with errors of the Index Provider or its agents will generally be borne by the Fund and its shareholders. For example, during a period where the Underlying Index contains incorrect constituents, the Fund would have market exposure to such constituents and would be underexposed to the Underlying Index’s other constituents. Such errors may negatively or positively impact the Fund and its shareholders.

Apart from scheduled rebalances, the Index Provider or its agents may carry out additional ad hoc rebalances to the Underlying Index in order, for example, to correct an error in the selection of index constituents. When the Underlying Index is rebalanced and the Fund in turn rebalances its portfolio to attempt to increase the correlation between the Fund’s portfolio and the Underlying Index, any transaction costs and market exposure arising from such portfolio rebalancing will be borne directly by the Fund and its shareholders. Unscheduled rebalances to the Underlying Index may expose the Fund to additional tracking error risk, which is the risk that the Fund’s returns may not track those of the Underlying Index. Therefore, errors and additional ad hoc rebalances carried out by the Index Provider or its agents to the Underlying Index may increase the costs to and the tracking error risk of the Fund.

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Small Cap Securities Risk (Russell 2000 Small-Cap Index Fund) — Small cap companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a small number of key personnel. If a product fails or there are other adverse developments, or if management changes, the Fund’s investment in a small cap company may lose substantial value. 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.

The securities of small cap companies generally trade in lower volumes and are subject to greater and more unpredictable price changes than larger cap securities or the market as a whole. In addition, small cap securities may be particularly sensitive to changes in interest rates, borrowing costs and earnings. Investing in small cap securities requires a longer term view.

Other Risks of Investing in the Funds

Each Fund may also be subject to certain other risks associated with its investments and investment strategies, including:

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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.

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Concentration Risk — The Fund reserves the right to concentrate its investments (i.e., invest 25% or more of its total assets in securities of issuers in a particular industry) to approximately the same extent that the Underlying Index concentrates in a particular industry. To the extent the Fund concentrates in a particular industry, it may be more susceptible to economic conditions and risks affecting that industry.

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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

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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 liquidity risk. 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.

■	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:
	Volatility 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 with the overall securities markets.
	Counterparty Risk — Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation.
	Market and Liquidity Risk — Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. 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. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund’s derivatives positions to lose value.
	Valuation Risk — 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 may also 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.
	Hedging Risk — When a derivative is used as a hedge against a position that the Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund’s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences noted below.
	Tax Risk — The federal income tax treatment of a derivative may not be as favorable as a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments. As a result, a larger portion of the Fund’s distributions may be treated as ordinary income rather than capital gains. In addition, certain derivatives are subject to mark-to-market or straddle provisions of the Internal Revenue Code. If such provisions are applicable, there could be an increase (or decrease) in the amount of taxable dividends paid by the Fund. In addition, the tax treatment of certain derivatives, such as swaps, is unsettled and may be subject to future legislation, regulation or administrative pronouncements issued by the Internal Revenue Service (“IRS”).

Regulatory Risk — Derivative contracts, including, without limitation, swaps, currency forwards and non-deliverable forwards, are subject to regulation under the Dodd-Frank Wall Street Reform and Consumer Protection Act (“Dodd-Frank Act”) in the United States and under comparable regimes in Europe, Asia and other non-U.S. jurisdictions. Under the Dodd-Frank Act, certain derivatives are subject to margin requirements and swap dealers are required to collect margin from the Fund with respect to such derivatives. Specifically, regulations are now in effect that require swap dealers to post and collect variation margin (comprised of specified liquid instruments and subject to a required haircut) in connection with trading of over-the-counter (“OTC”) swaps with the Fund. Shares of investment companies (other than certain money market funds) may not be posted as collateral under these regulations. Requirements for posting of initial margin in connection with OTC swaps will be phased-in through 2020. In addition, regulations adopted by prudential regulators that will begin to take effect in 2019 will require certain bank-regulated counterparties and certain of their affiliates to include in certain financial contracts, including many derivatives contracts, terms that delay or restrict the rights of counterparties, such as the Fund, to terminate such contracts, foreclose upon collateral, exercise other default rights or restrict transfers of credit support in the event that the counterparty and/or its affiliates are subject to certain types of resolution or insolvency proceedings. The implementation of these requirements with respect to derivatives, as well as regulations under the Dodd-Frank Act regarding clearing, mandatory trading and margining of other derivatives, may increase the costs and risks to the Fund of trading in these instruments and, as a result, may affect returns to investors in the Fund.

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Future regulatory developments may impact the Fund’s ability to invest or remain invested in certain derivatives. Legislation or regulation may also change the way in which the Fund itself is regulated. BlackRock cannot predict the effects of any new governmental regulation that may be implemented on the ability of the Fund to use swaps or any other financial derivative product, and there can be no assurance that any new governmental regulation will not adversely affect the Fund’s ability to achieve its investment objective.

Risks Specific to Certain Derivatives Used by the Fund

Swaps – Swap agreements, including total return swaps that may be referred to as contracts for difference, are two-party contracts entered into for periods ranging from a few weeks to more than one year. In a standard “swap” transaction, two parties agree to exchange the returns (or differentials in rates of return) earned or realized on particular predetermined investments or instruments, which can be adjusted for an interest factor. Swap agreements involve the risk that the party with whom the Fund has entered into the swap will default on its obligation to pay the Fund and the risk that the Fund will not be able to meet its obligations to pay the other party to the agreement. Swap agreements may also involve the risk that there is an imperfect correlation between the return on the Fund’s obligation to its counterparty and the return on referenced asset. In addition, swap agreements are subject to market and liquidity risk, leverage risk and hedging risk.

Forward Foreign Currency Exchange Contracts – Forward foreign currency exchange transactions are OTC contracts to purchase or sell a specified amount of a specified currency or multinational currency unit at a price and future date set at the time of the contract. Forward foreign currency exchange contracts do not eliminate fluctuations in the value of non-U.S. securities but rather allow the Fund to establish a fixed rate of exchange for a future point in time. This strategy can have the effect of reducing returns and minimizing opportunities for gain.

Indexed and Inverse Securities – Indexed and inverse securities provide a potential return based on a particular index of value or interest rates. The Fund’s return on these securities will be subject to risk with respect to the value of the particular index. These securities are subject to leverage risk and correlation risk. Certain indexed and inverse securities have greater sensitivity to changes in interest rates or index levels than other securities, and the Fund’s investment in such instruments may decline significantly in value if interest rates or index levels move in a way Fund management does not anticipate.

Futures – Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option; (b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.

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Expense Risk — Fund expenses are subject to a variety of factors, including fluctuations in the Fund’s net assets. Accordingly, actual expenses may be greater or less than those indicated. For example, to the extent that the Fund’s net assets decrease due to market declines or redemptions, the Fund’s expenses will increase as a percentage of Fund net assets. During periods of high market volatility, these increases in the Fund’s expense ratio could be significant.

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Investment in Other Investment Companies Risk — As with other investments, investments in other investment companies, including ETFs, are subject to market and selection risk. In addition, if the Fund acquires shares of investment companies, including ones affiliated with the Fund, shareholders bear both their proportionate share of expenses in the Fund (including management and advisory fees) and, indirectly, the expenses of the investment companies (to the extent not offset by BlackRock through waivers to the Fund’s management fees). To the extent the Fund is held by an affiliated fund, the ability of the Fund itself to hold other investment companies may be limited.

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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. As an open-end investment company registered with the Securities and Exchange Commission (the “SEC”), the Fund is subject to the federal securities laws, including the Investment Company Act of 1940, as amended (the “Investment Company Act”), the rules thereunder, and various SEC and SEC staff interpretive positions. In accordance with these laws, rules and positions, the Fund must “set aside” liquid assets (often referred to as “asset segregation”), or engage in other SEC- or staff-approved measures, to “cover” open positions with respect to certain kinds of instruments. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to

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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.

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Liquidity Risk — Liquidity risk exists when particular investments are difficult to purchase or sell. The Fund’s investments 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.

■	“New Issues” Risk (Russell 2000 Small-Cap Index Fund) — “New issues” are IPOs of equity securities. Investments in companies that have recently gone public have the potential to produce substantial gains for the Fund. However, there is no assurance that the Fund will have access to profitable IPOs and therefore investors should not rely on these past gains as an indication of future performance. The investment performance of the Fund during periods when it is unable to invest significantly or at all in IPOs may be lower than during periods when the Fund is able to do so. In addition, as the Fund increases in size, the impact of IPOs on the Fund’s performance will generally decrease. Securities issued in IPOs are subject to many of the same risks as investing in companies with smaller market capitalizations. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO. When an IPO is brought to the market, availability may be limited and the Fund may not be able to buy any shares at the offering price, or, if it is able to buy shares, it may not be able to buy as many shares at the offering price as it would like.
■	Passive Investment Risk — Because BlackRock does not select individual companies in the index that the Fund tracks, the Fund may hold securities of companies that present risks that an investment adviser researching individual securities might seek to avoid.
■	REIT Investment Risk — In addition to the risks facing real estate-related securities, such as a decline in property values due to increasing vacancies, a decline in rents resulting from unanticipated economic, legal or technological developments or a decline in the price of securities of real estate companies due to a failure of borrowers to pay their loans or poor management, investments in REITs involve unique risks. REITs may have limited financial resources, may trade less frequently and in limited volume and may be more volatile than other securities. In addition, recently enacted tax legislation permits a direct REIT shareholder to claim a 20% “qualified business income” deduction for ordinary REIT dividends, but does not permit a regulated investment company to pass through to its shareholders the special character of this income. Ordinary REIT dividends received by the Fund and distributed to the Fund’s shareholders also will generally not constitute “qualified dividend income.“ Therefore, the tax rate applicable to that portion of the dividend income attributable to ordinary REIT dividends received by the Fund will be taxed at a higher rate than dividends eligible for special treatment.

■	Repurchase Agreements Risk — If the other party to a repurchase agreement 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 and the market value of the security declines, the Fund may lose money.
■	Securities Lending Risk — Securities lending involves the risk that the borrower may fail to return the securities in a timely manner or at all. As a result, the Fund may lose money and there may be a delay in recovering the loaned securities. The Fund could also lose money if it does not recover the securities and/or the value of the collateral falls, including the value of investments made with cash collateral. These events could trigger adverse tax consequences for the Fund.
■	Short Sales Risk — Because making short sales in securities that it does not own exposes the Fund to the risks associated with those securities, such short sales involve speculative exposure risk. The Fund will incur a loss as a result of a short sale if the price of the security increases between the date of the short sale and the date on which the Fund replaces the security sold short. The Fund will realize a gain if the security declines in price between those dates. As a result, if the Fund makes short sales in securities that increase in value, it will likely underperform similar funds that do not make short sales in securities they do not own. There can be no assurance that the Fund will be able to close out a short sale position at any particular time or at an acceptable price. Although the Fund’s gain is limited to the amount at which it sold a security short, its potential loss is limited only by the maximum attainable price of the security, less the price at which the security was sold. The Fund may also pay transaction costs and borrowing fees in connection with short sales.
■	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

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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.

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When-Issued and Delayed Delivery Securities and Forward Commitments Risk (Russell 2000 Small-Cap Index Fund) — When-issued and delayed delivery securities and forward commitments involve the risk that the security the Fund buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the Fund may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security’s price.

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Account Information

How to Choose the Share Class that Best Suits Your Needs

Each Fund currently offers multiple share classes (Investor A and Institutional Shares in this prospectus), each with its own expense structure, allowing you to invest in the way that best suits your needs. Each share class represents an ownership interest in the same investment portfolio of the particular Fund. When you choose your class of shares, you should consider the size of your investment and how long you plan to hold your shares. Either your financial professional or 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”) can help you determine which share class is best suited to your personal financial goals. Investor A Shares are sometimes referred to herein as “Investor Shares.”

Each Fund’s shares are distributed by BlackRock Investments, LLC (the “Distributor”), an affiliate of BlackRock.

The table below summarizes key features of each of the share classes of the Funds.

Share Classes at a Glance ¹

	Investor A Shares	Institutional Shares
Availability	Generally available through Financial Intermediaries.	Limited to certain investors, including: • 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 Distributor to purchase such shares. • 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 Distributor to purchase such shares. • Employees, officers and directors/trustees of BlackRock or its affiliates and immediate family members of such persons, if they open an account directly with BlackRock. • Participants in certain programs sponsored by BlackRock or its affiliates or other Financial Intermediaries. • Clients investing through Financial Intermediaries that have entered into an agreement with the Distributor to offer such shares on a platform that charges a transaction based sales commission outside of the Fund.

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	Investor A Shares	Institutional Shares
Minimum Investment	$1,000 for all accounts except: • $50, if establishing an Automatic Investment Plan (“AIP”). • 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 investment minimum 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. • Employees, officers and directors/trustees of BlackRock or its affiliates and immediate family members of such persons, if they open an account directly with BlackRock. • Investors of Financial Intermediaries that: (i) charge such investors a fee for advisory, investment consulting, or similar services or (ii) have entered into an agreement with the Distributor to offer Institutional Shares through a no-load program or investment platform. $2 million for individuals and Institutional Investors. $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.
Initial Sales Charge?	No. Entire purchase price is invested in shares of the Fund.	No. Entire purchase price is invested in shares of the Fund.
Deferred Sales Charge?	No.	No.
Distribution and Service (12b-1) Fees?	No Distribution Fee. 0.25% Annual Service Fee.	No.
Redemption Fees?	No.	No.
Conversion to Investor A Shares?	N/A	No.
Advantage	Generally available.	No annual service fee.
Disadvantage	Annual service fee.	Limited availability.

¹	Please see “Details About the Share Classes” for more information about each share class.

The following pages will cover the additional details of each share class, including the eligibility requirements to purchase Institutional Shares.

More information about existing sales charge reductions and waivers is available free of charge in a clear and prominent format via hyperlink at www.blackrock.com and in the SAI, which is available on the website or on request.

Details About the Share Classes

Investor A Shares

Investor A Shares of each Fund pay an ongoing service fee of 0.25% per year. The Distributor normally pays the annual 0.25% Investor A Shares service fee to dealers on a monthly basis.

Institutional Shares

Institutional Shares are not subject to any sales charge. Only certain investors are eligible to buy Institutional Shares. Your Financial Intermediary can help you determine whether you are eligible to buy Institutional Shares. Each Fund may permit a lower initial investment for certain investors if their purchase, combined with purchases by other investors received together by a Fund, meets the minimum investment requirement.

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Institutional Shares may also be available on certain brokerage platforms. An investor transacting in Institutional Shares through a broker acting as an agent for the investor may be required to pay a commission and/or other forms of compensation to the broker. Shares of the Fund are available in other share classes that have different fees and expenses.

Eligible Institutional Share investors include the following:

■	Individuals and “Institutional Investors” with a minimum initial investment of $2 million who may purchase shares of a Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares;
■	Investors of Financial Intermediaries that: (i) charge such investors a fee for advisory, investment consulting, or similar services or (ii) have entered into an agreement with the Distributor to offer Institutional Shares through a no-load program or investment platform, in each case, with no minimum initial investment;
■	Clients investing through Financial Intermediaries that have entered into an agreement with the Distributor to offer such shares on a platform that charges a transaction based sales commission outside of the Fund, with a minimum initial investment of $1,000;
■	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 is not subject to any minimum initial investment and may purchase shares of a Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares;

■

Trust department clients of PNC Bank and Bank of America, N.A. and their affiliates for whom they (i) act in a fiduciary capacity (excluding participant directed employee benefit plans); (ii) otherwise have investment discretion; or (iii) act as custodian for at least $2 million in assets, who are not subject to any minimum initial investment;

■	Holders of certain Bank of America Corporation (“BofA Corp”) sponsored unit investment trusts (“UITs”) who reinvest dividends received from such UITs in shares of a Fund, who are not subject to any minimum initial investment; and
■	Employees, officers and directors/trustees of BlackRock, Inc., mutual funds sponsored and advised by BlackRock or its affiliates (“BlackRock Funds”), BofA Corp., PNC, Barclays PLC or their respective affiliates and immediate family members of such persons, if they open an account directly with BlackRock, who are not subject to any minimum initial investment.

The Funds reserve the right to modify or waive the above-stated policies at any time.

Right of Accumulation

Investors have a “right of accumulation” under which the current value of an investor’s existing Investor A and A1, Investor B, Investor C, C1, C2 and C3, and Institutional Shares in most BlackRock Funds and the investment in the BlackRock CollegeAdvantage 529 Program by the investor or by or on behalf of the investor’s spouse and children may be combined with the amount of the current purchase in determining whether an investor qualifies for a breakpoint and a reduced front-end sales charge. Financial Intermediaries may value current holdings of their customers differently for purposes of determining whether an investor qualifies for a breakpoint and a reduced front-end sales charge, although customers of the same Financial Intermediary will be treated similarly. In order to use this right, the investor must alert BlackRock to the existence of any previously purchased shares.

Distribution and Shareholder Servicing Payments

Plan Payments

The Corporation, on behalf of the Funds, has adopted a plan (the “Plan”) pursuant to Rule 12b-1 under the Investment Company Act with respect to the Investor Shares that allows a Fund to pay distribution fees for the sale of its shares and/or shareholder servicing fees for certain services provided to its shareholders. Institutional and Investor A Shares do not pay distribution fees.

Under the Plan, the Funds pay shareholder servicing fees (also referred to as general shareholder liaison services fees) to Financial Intermediaries for providing support services to their customers who own Investor Shares of the Fund. The shareholder servicing fee payment is calculated as a percentage of the average daily net asset value of Investor Shares of the Fund. All Investor Shares pay this shareholder servicing fee. Institutional Shares do not pay a shareholder servicing fee.

In return for the shareholder servicing fee, Financial Intermediaries (including BlackRock) may provide one or more of the following services to their customers who own Investor Shares:

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■	Answering customer inquiries regarding account status and history, the manner in which purchases, exchanges and redemptions or repurchases of shares may be effected and certain other matters pertaining to the customers’ investments;
■	Assisting customers in designating and changing dividend options, account designations and addresses; and
■	Providing other similar shareholder liaison services.

The shareholder servicing fees payable pursuant to the Plan are paid to compensate Financial Intermediaries for the administration and servicing of shareholder accounts and are not costs which are primarily intended to result in the sale of a Fund’s shares. Because the fees paid by a Fund under the Plan are paid out of Fund assets on an ongoing basis, over time these fees will increase the cost of your investment and may cost you more than paying other types of sales charges. For more information on the Plan, including a complete list of services provided thereunder, see the SAI.

Other Payments by the Funds

In addition to fees that a Fund may pay to a Financial Intermediary pursuant to the Plan and fees a Fund pays to its transfer agent, BNY Mellon Investment Servicing (US) Inc. (the “Transfer Agent”), BlackRock, on behalf of a Fund, may enter into non-Plan agreements with affiliated and unaffiliated Financial Intermediaries pursuant to which the Fund will pay a Financial Intermediary for administrative, networking, recordkeeping, sub-transfer agency, sub-accounting and/or shareholder services. These non-Plan payments are generally based on either (1) a percentage of the average daily net assets of Fund shareholders serviced by a Financial Intermediary or (2) a fixed dollar amount for each account serviced by a Financial Intermediary. The aggregate amount of these payments may be substantial.

Other Payments by BlackRock

From time to time, BlackRock, the Distributor or their affiliates also may pay a portion of the fees for administrative, networking, recordkeeping, sub-transfer agency, sub-accounting and shareholder services described above at its or their own expense and out of its or their profits. BlackRock, the Distributor and their affiliates may also compensate affiliated and unaffiliated Financial Intermediaries for the sale and distribution of shares of the Funds. These payments would be in addition to the Fund payments described in this prospectus and may be a fixed dollar amount, may be based on the number of customer accounts maintained by the Financial Intermediary, may be based on a percentage of the value of shares sold to, or held by, customers of the Financial Intermediary or may be calculated on another basis. The aggregate amount of these payments by BlackRock, the Distributor and their affiliates may be substantial and, in some circumstances, may create an incentive for a Financial Intermediary, its employees or associated persons to recommend or sell shares of a Fund to you.

Please contact your Financial Intermediary for details about payments it may receive from a Fund or from BlackRock, the Distributor or their affiliates. For more information, see the SAI.

How to Buy, Sell, Exchange and Transfer Shares

The chart on the following pages summarizes how to buy, sell, exchange and transfer shares through your Financial Intermediary. You may also buy, sell, exchange and transfer shares through BlackRock if your account is held directly with BlackRock. To learn more about buying, selling, exchanging or transferring shares through BlackRock, call (800) 441-7762. Because the selection of a mutual fund involves many considerations, your Financial Intermediary may help you with this decision.

With certain limited exceptions, the Funds are generally available only to investors residing in the United States and may not be distributed by a foreign Financial Intermediary. Under this policy, in order to accept new accounts or additional investments (including by way of exchange from another BlackRock Fund) into existing accounts, the Funds generally require that (i) a shareholder that is a natural person be a U.S. citizen or resident alien, in each case residing within the United States or a U.S. territory (including APO/FPO/DPO addresses), and have a valid U.S. taxpayer identification number, and (ii) a Financial Intermediary or a shareholder that is an entity be domiciled in the United States and have a valid U.S. taxpayer identification number or be domiciled in a U.S. territory and have a valid U.S. taxpayer identification number or IRS Form W-8. Any existing account that is updated to reflect a non-U.S. address will also be restricted from making additional investments.

Each Fund may reject any purchase order, modify or waive the minimum initial or subsequent investment requirements for any shareholders and suspend and resume the sale of any share class of the Fund at any time for any reason. In addition, the Funds may waive certain requirements regarding the purchase, sale, exchange or transfer of shares described below.

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Under certain circumstances, if no activity occurs in an account within a time period specified by state law, a shareholder’s shares in a Fund may be transferred to that state.

How to Buy Shares

	Your Choices	Important Information for You to Know
Initial Purchase	First, select the share class appropriate for you	Refer to the “Share Classes at a Glance” table in this prospectus (be sure to read this prospectus carefully). When you place your initial order, you must indicate which share class you select (if you do not specify a share class and do not qualify to purchase Institutional Shares, you will receive Investor A Shares). Certain factors, such as the amount of your investment, your time frame for investing and your financial goals, may affect which share class you choose. Your Financial Intermediary can help you determine which share class is appropriate for you.
	Next, determine the amount of your investment	Refer to the minimum initial investment in the “Share Classes at a Glance” table of this prospectus.
	Have your Financial Intermediary submit your purchase order	The price of your shares is based on the next calculation of the Fund’s net asset value after your order is placed. Any purchase orders placed prior to the close of business on the New York Stock Exchange (the “NYSE”) (generally 4:00 p.m. Eastern time) will be priced at the net asset value determined that day. Certain Financial Intermediaries, however, may require submission of orders prior to that time. Purchase orders placed after that time will be priced at the net asset value determined on the next business day. A broker-dealer or financial institution maintaining the account in which you hold shares may charge a separate account, service or transaction fee on the purchase or sale of Fund shares that would be in addition to the fees and expenses shown in the Fund’s “Fees and Expenses” table. The Fund may reject any order to buy shares and may suspend the sale of shares at any time. Certain Financial Intermediaries may charge a processing fee to confirm a purchase.
	Or contact BlackRock (for accounts held directly with BlackRock)	To purchase shares directly from BlackRock, call (800) 441-7762 and request a new account application. Mail the completed application along with a check payable to “BlackRock Funds” to the Transfer Agent at the address on the application.
Add to Your Investment	Purchase additional shares	For Investor A Shares, the minimum investment for additional purchases is generally $50 for all accounts (with the exception of certain employer-sponsored retirement plans which may have a lower minimum for additional purchases). The minimums for additional purchases may be waived under certain circumstances. Institutional Shares have no minimum for additional purchases.
	Have your Financial Intermediary submit your purchase order for additional shares	To purchase additional shares you may contact your Financial Intermediary. For more details on purchasing by Internet see below.
	Or contact BlackRock (for accounts held directly with BlackRock)	Purchase by Telephone: Call (800) 441-7762 and speak with one of our representatives. The Fund has the right to reject any telephone request for any reason. Purchase in Writing: You may send a written request to BlackRock at the address on the back cover of this prospectus. Purchase by VRU: Investor A Shares may also be purchased by use of the Fund’s automated voice response unit (“VRU”) service at (800) 441-7762. Purchase by Internet: You may purchase your shares and view activity in your account by logging onto the BlackRock website at www.blackrock.com. Purchases made on the Internet using the Automated Clearing House (“ACH”) will have a trade date that is the day after the purchase is made. Certain institutional clients’ purchase orders of Institutional Shares placed by wire prior to the close of business on the NYSE will be priced at the net asset value determined that day. Contact your Financial Intermediary or BlackRock for further

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	Your Choices	Important Information for You to Know
Add to Your Investment (continued)	Or contact BlackRock (for accounts held directly with BlackRock) (continued)	information. The Fund limits Internet purchases in shares of the Fund to $25,000 per trade. Different maximums may apply to certain institutional investors. Please read the On-Line Services Disclosure Statement and User Agreement, the Terms and Conditions page and the Consent to Electronic Delivery Agreement (if you consent to electronic delivery), before attempting to transact online. The Fund employs reasonable procedures to confirm that transactions entered over the Internet are genuine. By entering into the User Agreement with the Fund in order to open an account through the website, the shareholder waives any right to reclaim any losses from the Fund or any of its affiliates incurred through fraudulent activity.
	Acquire additional shares by reinvesting dividends and capital gains	All dividends and capital gains distributions are automatically reinvested without a sales charge. To make any changes to your dividend and/or capital gains distributions options, please call (800) 441-7762 or contact your Financial Intermediary (if your account is not held directly with BlackRock).
	Participate in the Automatic Investment Plan (“AIP”)	BlackRock’s AIP allows you to invest a specific amount on a periodic basis from your checking or savings account into your investment account. Refer to the “Account Services and Privileges” section of this prospectus for additional information.
How to Pay for Shares	Making payment for purchases	Payment for an order must be made in Federal funds or other immediately available funds by the time specified by your Financial Intermediary, but in no event later than 4:00 p.m. (Eastern time) on the first business day following BlackRock’s receipt of the order. If payment is not received by this time, the order will be canceled and you and your Financial Intermediary will be responsible for any loss to the Fund. For shares purchased directly from the Fund, a check payable to BlackRock Funds which bears the name of the Fund must accompany a completed purchase application. There is a $20 fee for each purchase check that is returned due to insufficient funds. The Fund does not accept third-party checks. You may also wire Federal funds to the Fund to purchase shares, but you must call (800) 441-7762 before doing so to confirm the wiring instructions.

How to Sell Shares

	Your Choices	Important Information for You to Know
Full or Partial Redemption of Shares	Have your Financial Intermediary submit your sales order	You can make redemption requests through your Financial Intermediary. Shareholders should indicate whether they are redeeming Investor A or Institutional Shares. The price of your shares is based on the next calculation of the Fund’s net asset value after your order is placed. For your redemption request to be priced at the net asset value on the day of your request, you must submit your request to your Financial Intermediary prior to that day’s close of business on the NYSE (generally 4:00 p.m. Eastern time). Certain Financial Intermediaries, however, may require submission of orders prior to that time. Any redemption request placed after that time will be priced at the net asset value at the close of business on the next business day. Regardless of the method the Fund uses to make payment of your redemption proceeds (check, wire or ACH), your redemption proceeds typically will be sent one to two business days after your request is submitted, but in any event, within seven days. Certain Financial Intermediaries may charge a fee to process a redemption of shares. The Fund may reject an order to sell shares under certain circumstances.
	Selling shares held directly with BlackRock	Methods of Redeeming Redeem by Telephone: You may sell Investor A Shares held directly with BlackRock by telephone request if certain conditions are met and if the amount being sold is less than (i) $100,000 for payments by check or

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	Your Choices	Important Information for You to Know
Full or Partial Redemption of Shares (continued)	Selling shares held directly with BlackRock (continued)	(ii) $250,000 for payments through ACH or wire transfer. Certain redemption requests, such as those in excess of these amounts, must be in writing with a medallion signature guarantee. For Institutional Shares, certain redemption requests may require written instructions with a medallion signature guarantee. Call (800) 441-7762 for details. You can obtain a medallion signature guarantee stamp from a bank, securities dealer, securities broker, credit union, savings and loan association, national securities exchange or registered securities association. A notary public seal will not be acceptable. The Fund, its administrator and the Distributor will employ reasonable procedures to confirm that instructions communicated by telephone are genuine. The Fund and its service providers will not be liable for any loss, liability, cost or expense for acting upon telephone instructions that are reasonably believed to be genuine in accordance with such procedures. The Fund may refuse a telephone redemption request if it believes it is advisable to do so. During periods of substantial economic or market change, telephone redemptions may be difficult to complete. Please find alternative redemption methods below. Redeem by VRU: Investor A Shares may also be redeemed by use of the Fund’s automated VRU service. Payment for Investor A Shares redeemed by the VRU service may be made for non-retirement accounts in amounts up to $25,000, either through check, ACH or wire. Redeem by Internet: You may redeem in your account by logging onto the BlackRock website at www.blackrock.com. Proceeds from Internet redemptions may be sent via check, ACH or wire to the bank account of record. Payment for Investor A Shares redeemed by Internet may be made for non-retirement accounts in amounts up to $25,000, either through check, ACH or wire. Different maximums may apply to investors in Institutional Shares. Redeem in Writing: You may sell shares held with BlackRock by writing to BlackRock, P.O. Box 9819, Providence, Rhode Island 02940-8019 or for overnight delivery, 4400 Computer Drive, Westborough, Massachusetts 01588. All shareholders on the account must sign the letter. A medallion signature guarantee will generally be required but may be waived in certain limited circumstances. You can obtain a medallion signature guarantee stamp from a bank, securities dealer, securities broker, credit union, savings and loan association, national securities exchange or registered securities association. A notary public seal will not be acceptable. If you hold stock certificates, return the certificates with the letter. Proceeds from redemptions may be sent via check, ACH or wire to the bank account of record. Payment of Redemption Proceeds Redemption proceeds may be paid by check or, if the Fund has verified banking information on file, through ACH or by wire transfer. Payment by Check: BlackRock will normally mail redemption proceeds within three business days following receipt of a properly completed request, but in any event within seven days. Shares can be redeemed by telephone and the proceeds sent by check to the shareholder at the address on record. Shareholders will pay $15 for redemption proceeds sent by check via overnight mail. You are responsible for any additional charges imposed by your bank for this service. The Fund reserves the right to reinvest any dividend or distribution amounts ( e.g. , income dividends or capital gains) which you have elected to receive by check should your check be returned as undeliverable or remain uncashed for more than 6 months. No interest will accrue on amounts represented by uncashed checks. Your check will be reinvested in your account at the net asset value next calculated, on the day of the investment. When reinvested, those amounts are subject to the risk of loss like any fund investment. If you elect to receive distributions in cash and a check remains undeliverable

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	Your Choices	Important Information for You to Know
Full or Partial Redemption of Shares (continued)	Selling shares held directly with BlackRock (continued)	or uncashed for more than 6 months, your cash election may also be changed automatically to reinvest and your future dividend and capital gains distributions will be reinvested in the Fund at the net asset value as of the date of payment of the distribution. Payment by Wire Transfer: Payment for redeemed shares for which a redemption order is received before 4:00 p.m. (Eastern time) on a business day is normally made in Federal funds wired to the redeeming shareholder on the next business day, provided that the Fund’s custodian is also open for business. Payment for redemption orders received after 4:00 p.m. (Eastern time) or on a day when the Fund’s custodian is closed is normally wired in Federal funds on the next business day following redemption on which the Fund’s custodian is open for business. The Fund reserves the right to wire redemption proceeds within seven days after receiving a redemption order if, in the judgment of the Fund, an earlier payment could adversely affect the Fund. If a shareholder has given authorization for expedited redemption, shares can be redeemed by Federal wire transfer to a single previously designated bank account. Shareholders will pay $7.50 for redemption proceeds sent by Federal wire transfer. You are responsible for any additional charges imposed by your bank for this service. No charge for wiring redemption payments with respect to Institutional Shares is imposed by the Fund. The Fund is not responsible for the efficiency of the Federal wire system or the shareholder’s firm or bank. To change the name of the single, designated bank account to receive wire redemption proceeds, it is necessary to send a written request to the Fund at the address on the back cover of this prospectus. Payment by ACH: Redemption proceeds may be sent to the shareholder’s bank account (checking or savings) via ACH. Payment for redeemed shares for which a redemption order is received before 4:00 p.m. (Eastern time) on a business day is normally sent to the redeeming shareholder the next business day, with receipt at the receiving bank within the next two business days (48-72 hours), provided that the Fund’s custodian is also open for business. Payment for redemption orders received after 4:00 p.m. (Eastern time) or on a day when the Fund’s custodian is closed is normally sent on the next business day following redemption on which the Fund’s custodian is open for business. The Fund reserves the right to send redemption proceeds within seven days after receiving a redemption order if, in the judgment of the Fund, an earlier payment could adversely affect the Fund. No charge for sending redemption payments via ACH is imposed by the Fund. *** If you make a redemption request before the Fund has collected payment for the purchase of shares, the Fund may delay mailing your proceeds. This delay will usually not exceed ten days.
Redemption Proceeds		Under normal circumstances, a Fund expects to meet redemption requests by using cash or cash equivalents in its portfolio or by selling portfolio assets to generate cash. During periods of stressed market conditions, when a significant portion of the Fund’s portfolio may be comprised of less-liquid investments, the Fund may be more likely to limit cash redemptions and may determine to pay redemption proceeds by (i) borrowing under a line of credit it has entered into with a group of lenders, (ii) borrowing from another BlackRock Fund pursuant to an interfund lending program, to the extent permitted by the Fund’s investment policies and restrictions as set forth in the SAI, and/or (iii) transferring portfolio securities in-kind to you. The SAI includes more information about the Fund’s line of credit and interfund lending program, to the extent applicable.

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	Your Choices	Important Information for You to Know
Redemption Proceeds (continued)	(continued)	If the Fund pays redemption proceeds by transferring portfolio securities in-kind to you, you may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of redemption.

How to Exchange Shares or Transfer Your Account

	Your Choices	Important Information for You to Know
Exchange Privilege	Selling shares of one BlackRock Fund to purchase shares of another BlackRock Fund (“exchanging”)	Investor or Institutional Shares of the Fund are generally exchangeable for shares of the same class of another BlackRock Fund. You can exchange $1,000 or more of Investor Shares from one fund into the same class of another fund which offers that class of shares (you can exchange less than $1,000 of Investor Shares if you already have an account in the fund into which you are exchanging). Investors who currently own Institutional Shares of the Fund may make exchanges into Institutional Shares of other BlackRock Funds except for investors holding shares through certain client accounts at Financial Intermediaries that are omnibus with the Fund and do not meet applicable minimums. There is no required minimum amount with respect to exchanges of Institutional Shares. You may only exchange into a share class and fund that are open to new investors or in which you have a current account if the fund is closed to new investors. Some of the BlackRock Funds impose a different initial or deferred sales charge schedule. Therefore the exchange of Investor A Shares may be subject to that sales charge. Investor A Shares of the Fund that were obtained with the exchange privilege and that originally were shares of a BlackRock Fund that were subject to a sales charge can be exchanged for Investor A Shares of another BlackRock Fund based on their respective NAVs. The CDSC will continue to be measured from the date of the original purchase. The CDSC schedule applicable to your original purchase will apply to the shares you receive in the exchange and any subsequent exchange. To exercise the exchange privilege, you may contact your Financial Intermediary. Alternatively, if your account is held directly with BlackRock, you may: (i) call (800) 441-7762 and speak with one of our representatives, (ii) make the exchange via the Internet by accessing your account online at www.blackrock.com, or (iii) send a written request to the Fund at the address on the back cover of this prospectus. Please note, if you indicated on your New Account Application that you did not want the Telephone Exchange Privilege, you will not be able to place exchanges via the telephone until you update this option either in writing or by calling (800) 441-7762. The Fund has the right to reject any telephone request for any reason. Although there is currently no limit on the number of exchanges that you can make, the exchange privilege may be modified or terminated at any time in the future. The Fund may suspend or terminate your exchange privilege at any time for any reason, including if the Fund believes, in its sole discretion, that you are engaging in market timing activities. See “Short-Term Trading Policy” below. For U.S. federal income tax purposes a share exchange is a taxable event and a capital gain or loss may be realized. Please consult your tax adviser or other Financial Intermediary before making an exchange request.
Transfer Shares to Another Financial Intermediary	Transfer to a participating Financial Intermediary	You may transfer your shares of the Fund only to another Financial Intermediary that has entered into an agreement with the Distributor. Certain shareholder services may not be available for the transferred shares. All future trading of these assets must be coordinated by the receiving firm.

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	Your Choices	Important Information for You to Know
Transfer Shares to Another Financial Intermediary (continued)	Transfer to a participating Financial Intermediary (continued)	If your account is held directly with BlackRock, you may call (800) 441-7762 with any questions; otherwise please contact your Financial Intermediary to accomplish the transfer of shares.
	Transfer to a non-participating Financial Intermediary	You must either: • Transfer your shares to an account with the Fund; or • Sell your shares. If your account is held directly with BlackRock, you may call (800) 441-7762 with any questions; otherwise please contact your Financial Intermediary to accomplish the transfer of shares.

Account Services and Privileges

The following table provides examples of account services and privileges available in your BlackRock account. Certain of these account services and privileges are only available to shareholders of Investor Shares whose accounts are held directly with BlackRock. If your account is held directly with BlackRock, please call (800) 441-7762 or visit www.blackrock.com for additional information as well as forms and applications. Otherwise, please contact your Financial Intermediary for assistance in requesting one or more of the following services and privileges.

Automatic Investment Plan	Allows systematic investments on a periodic basis from your checking or savings account.	BlackRock’s AIP allows you to invest a specific amount on a periodic basis from your checking or savings account into your investment account. You may apply for this option upon account opening or by completing the Automatic Investment Plan application. The minimum investment amount for an automatic investment is $50 per portfolio.
Dividend Allocation Plan	Automatically invests your distributions into another BlackRock Fund of your choice pursuant to your instructions, without any fees or sales charges.	Dividend and capital gains distributions may be reinvested in your account to purchase additional shares or paid in cash. Using the Dividend Allocation Plan, you can direct your distributions to your bank account (checking or savings), to purchase shares of another fund at BlackRock without any fees or sales charges, or by check to a special payee. Please call (800) 441-7762 for details. If investing in another BlackRock Fund, the receiving fund must be open to new purchases.
EZ Trader	Allows an investor to purchase or sell Investor A Shares by telephone or over the Internet through ACH.	(NOTE: This option is offered to shareholders whose accounts are held directly with BlackRock. Please speak with your Financial Intermediary if your account is held elsewhere.) Prior to establishing an EZ Trader account, please contact your bank to confirm that it is a member of the ACH system. Once confirmed, complete an application, making sure to include the appropriate bank information, and return the application to the address listed on the form. Prior to placing a telephone or Internet purchase or sale order, please call (800) 441-7762 to confirm that your bank information has been updated on your account. Once this is established, you may place your request to sell shares with the Fund by telephone or Internet. Proceeds will be sent to your pre-designated bank account.
Systematic Exchange Plan	This feature can be used by investors to systematically exchange money from one fund to up to four other funds.	A minimum of $10,000 in the initial BlackRock Fund is required, and investments in any additional funds must meet minimum initial investment requirements.
Systematic Withdrawal Plan (“SWP”)	This feature can be used by investors who want to receive regular distributions from their accounts.	To start an SWP, a shareholder must have a current investment of $10,000 or more in a BlackRock Fund. Shareholders can elect to receive cash payments of $50 or more at any interval they choose. Shareholders may sign up by completing the SWP Application Form, which may be obtained from BlackRock. Shareholders should realize that if withdrawals exceed income the invested principal in their account will be depleted. To participate in the SWP, shareholders must have their dividends reinvested. Shareholders may change or cancel the SWP at any time, with a minimum of 24 hours’ notice. If a shareholder purchases additional Investor A Shares of a fund at the same time he or she

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Systematic Withdrawal Plan (“SWP”) (continued)

This feature can be used by investors who want to receive regular distributions from their accounts. (continued)

redeems shares through the SWP, that investor may lose money because of any applicable sales charge.

Ask your Financial Intermediary for details.

Funds’ Rights

Each Fund may:

■	Suspend the right of redemption if trading is halted or restricted on the NYSE or under other emergency conditions described in the Investment Company Act;
■	Postpone the date of payment upon redemption if trading is halted or restricted on the NYSE or under other emergency conditions described in the Investment Company Act or if a redemption request is made before the Fund has collected payment for the purchase of shares;
■	Redeem shares for property other than cash as may be permitted under the Investment Company Act; and
■	Redeem shares involuntarily in certain cases, such as when the value of a shareholder account falls below a specified level.

Note on Low Balance Accounts. Because of the high cost of maintaining smaller shareholder accounts, BlackRock has set a minimum balance of $500 in each Fund position you hold within your account (“Fund Minimum”), and may redeem the shares in your account if the net asset value of those shares in your account falls below $500 for any reason, including market fluctuation.

You will be notified that the value of your account is less than the Fund Minimum before the Fund makes any involuntary redemption. This notification will provide you with a 90 calendar day period to make an additional investment in order to bring the value of your account to at least $500 before the Fund makes an involuntary redemption. This involuntary redemption will not charge any deferred sales charge, and may not apply to accounts of certain employer-sponsored retirement plans (not including IRAs), qualified state tuition plan (529 Plan) accounts, and select fee-based programs at your Financial Intermediary.

Participation in Fee-Based Programs

If you participate in certain fee-based programs offered by BlackRock or an affiliate of BlackRock or by Financial Intermediaries that have agreements with the Distributor, you may be able to buy Institutional Shares, including by exchange from other share classes. Sales charges on the shares being exchanged may be reduced or waived under certain circumstances. You generally cannot transfer shares held through a fee-based program into another account. Instead, you will have to redeem your shares held through the program and purchase shares of another class, which may be subject to distribution and service fees. This may be a taxable event and you will pay any applicable sales charges or redemption fees.

Shareholders that participate in a fee-based program generally have two options at termination. The program can be terminated and the shares liquidated, or the program can be terminated and the shares held in an account. In general, when a shareholder chooses to continue to hold the shares, whatever share class was held in the program can be held after termination. Shares that have been held for less than specified periods within the program may be subject to a fee upon redemption. Shareholders that held Investor A or Institutional Shares in the program are eligible to purchase additional shares of the respective share class of the Fund, but may be subject to upfront sales charges with respect to Investor A Shares. Additional purchases of Institutional Shares are permitted only if you have an existing position at the time of purchase or are otherwise eligible to purchase Institutional Shares.

Details about these features and the relevant charges are included in the client agreement for each fee-based program and are available from your Financial Intermediary.

Short-Term Trading Policy

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effect on the performance of a Fund and its returns to shareholders. For example, large flows of cash into and out of a Fund may require the management team to allocate a significant amount of assets to cash or other short-term investments or sell securities, rather than maintaining such assets in securities selected to achieve the Fund’s investment objective. Frequent trading may cause a Fund to sell securities at less favorable prices, and transaction costs, such as brokerage commissions, can reduce a Fund’s performance.

A fund’s investment in non-U.S. securities is subject to the risk that an investor may seek to take advantage of a delay between the change in value of a fund’s portfolio securities and the determination of the fund’s net asset value as a result of different closing times of U.S. and non-U.S. markets by buying or selling fund shares at a price that does not reflect their true value. A similar risk exists for funds that invest in securities of small capitalization companies, securities of issuers located in emerging markets or high yield securities (junk bonds) that are thinly traded and therefore may have actual values that differ from their market prices. This short-term arbitrage activity can reduce the return received by long-term shareholders. Each Fund will seek to eliminate these opportunities by using fair value pricing, as described in “Management of the Funds — Valuation of Fund Investments” below.

Each Fund discourages market timing and seeks to prevent frequent purchases and sales or exchanges of Fund shares that it determines may be detrimental to a Fund or long-term shareholders. The Board has approved the policies discussed below to seek to deter market timing activity. The Board has not adopted any specific numerical restrictions on purchases, sales and exchanges of Fund shares because certain legitimate strategies will not result in harm to a Fund or its shareholders.

If as a result of its own investigation, information provided by a Financial Intermediary or other third-party, or otherwise, a Fund believes, in its sole discretion, that your short-term trading is excessive or that you are engaging in market timing activity, it reserves the right to reject any specific purchase or exchange order. If a Fund rejects your purchase or exchange order, you will not be able to execute that transaction, and the Fund will not be responsible for any losses you therefore may suffer. For transactions placed directly with a Fund, the Fund may consider the trading history of accounts under common ownership or control for the purpose of enforcing these policies. Transactions placed through the same Financial Intermediary on an omnibus basis may be deemed part of a group for the purpose of this policy and may be rejected in whole or in part by a Fund. Certain accounts, such as omnibus accounts and accounts at Financial Intermediaries, however, include multiple investors and such accounts typically provide a Fund with net purchase or redemption and exchange requests on any given day where purchases, redemptions and exchanges of shares are netted against one another and the identity of individual purchasers, redeemers and exchangers whose orders are aggregated may not be known by a Fund. While the Funds monitor for market timing activity, the Funds may be unable to identify such activities because the netting effect in omnibus accounts often makes it more difficult to locate and eliminate market timers from the Funds. The Distributor has entered into agreements with respect to Financial Intermediaries that maintain omnibus accounts with the Funds pursuant to which such Financial Intermediaries undertake to cooperate with the Distributor in monitoring purchase, exchange and redemption orders by their customers in order to detect and prevent short-term or excessive trading in the Fund’s shares through such accounts. Identification of market timers may also be limited by operational systems and technical limitations. In the event that a Financial Intermediary is determined by a Fund to be engaged in market timing or other improper trading activity, the Distributor may terminate such Financial Intermediary’s agreement with the Distributor, suspend such Financial Intermediary’s trading privileges or take other appropriate actions.

There is no assurance that the methods described above will prevent market timing or other trading that may be deemed abusive.

The Funds may from time to time use other methods that they believe are appropriate to deter market timing or other trading activity that may be detrimental to the Fund or long-term shareholders.

Master/Feeder Structure

Russell 2000 Small-Cap Index Fund is a “feeder” fund that invests all of its assets in Master Small Cap Index Series of the Master LLC. Investors in Russell 2000 Small-Cap Index Fund will acquire an indirect interest in the Series.

Master Small Cap Index Series may accept investments from other feeder funds, and all the feeder funds of the Series bear the Series’ expenses in proportion to their assets. This structure may enable Russell 2000 Small-Cap Index Fund to reduce costs through economies of scale. A larger investment portfolio may also reduce certain transaction costs to the extent that contributions to and redemptions from the Series from different feeder funds may offset each other and produce a lower net cash flow.

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performance, than another feeder fund. In addition, large purchases or redemptions by one feeder fund could negatively affect the performance of other feeder funds that invest in the Series. Information about other feeder funds, if any, is available by calling (800) 441-7762.

Whenever the Series holds a vote of its feeder funds, Russell 2000 Small-Cap Index Fund will pass the vote through to its own shareholders. Smaller feeder funds may be harmed by the actions of larger feeder funds. For example, a larger feeder fund could have more voting power than Russell 2000 Small-Cap Index Fund over the operations of the Series.

Russell 2000 Small-Cap Index Fund may withdraw from the Series at any time and may invest all of its assets in another pooled investment vehicle or retain an investment adviser to manage the Fund’s assets directly.

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Management of the Funds

BlackRock

BlackRock is the investment manager for the Series in which Russell 2000 Small-Cap Index Fund invests and for MSCI EAFE International Index Fund. BlackRock manages the investments and business operations of the Series and MSCI EAFE International Index Fund, subject to the oversight of the Master LLC’s and Corporation’s Board of Directors, as applicable. While BlackRock is ultimately responsible for the management of the Series and MSCI EAFE International Index Fund, it is able to draw upon the trading, research and expertise of its asset management affiliates for portfolio decisions and management with respect to certain portfolio securities. BlackRock is an indirect, wholly-owned subsidiary of BlackRock, Inc.

BlackRock, a registered investment adviser, was organized in 1994 to perform advisory services for investment companies. BlackRock Fund Advisors (“BFA”), the sub-adviser to the Funds and an affiliate of BlackRock, is a registered investment adviser organized in 1984. BlackRock and its affiliates had approximately $6.317 trillion in investment company and other portfolio assets under management as of March 31, 2018.

The Master LLC and the Corporation have entered into separate agreements with BlackRock (each, a “Management Agreement”) pursuant to which BlackRock serves as manager to Master Small Cap Index Series and MSCI EAFE International Index Fund, as applicable. Pursuant to each Management Agreement, BlackRock is entitled to fees computed on a daily basis and payable monthly. Under each Management Agreement, the maximum annual fee rate payable by the Master LLC and the Corporation to BlackRock is 0.01% of the average daily net assets of each of Master Small Cap Index Series and MSCI EAFE International Index Fund respectively. For the fiscal year ended December 31, 2017, the Manager received a management fee, net of any applicable waivers, at an annual rate as a percentage of average daily net assets of Master Small Cap Index Series of 0.00% and MSCI EAFE International Index Fund of 0.01%.

The Corporation has entered into an agreement (the “Administration Agreement”) with BlackRock, as the administrator (in such capacity, the “Administrator”), pursuant to which the Administrator receives compensation paid on a monthly basis for its services to Russell 2000 Small-Cap Index Fund.

The contractual fee rate payable to the Administrator as a percentage of Russell 2000 Small-Cap Index Fund’s average daily net assets under the Administration Agreement is 0.04%.

For the fiscal year ended December 31, 2017, the administration fee rate, net of any applicable waivers, for Russell 2000 Small-Cap Index Fund was 0.00%.

BlackRock has contractually agreed to waive the management fee with respect to any portion of each of the Series’ and MSCI EAFE International Index Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and ETFs managed by BlackRock or its affiliates that have a contractual management fee, through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or the Corporation, as applicable, or by a vote of a majority of the outstanding voting securities of the Series or MSCI EAFE International Index Fund, as applicable.

BlackRock has voluntarily agreed to waive its management fees by the amount of investment advisory fees the Series or MSCI EAFE International Index Fund, as applicable, pays to BlackRock indirectly through its investment in affiliated money market funds (the “affiliated money market fund waiver”).

BlackRock has contractually agreed to cap net expenses (excluding (i) interest, taxes, dividends tied to short sales, brokerage commissions, and other expenditures which are capitalized in accordance with generally accepted accounting principles; (ii) expenses incurred directly or indirectly by a Fund as a result of investments in other investment companies and pooled investment vehicles; (iii) other expenses attributable to, and incurred as a result of, a Fund’s investments; and (iv) extraordinary expenses (including litigation expenses) not incurred in the ordinary course of a Fund’s business, if any) of each share class of the Funds at the levels shown below and in a Fund’s fees and expense table in the “Fund Overview” section of this prospectus. Items (i), (ii), (iii) and (iv) in the preceding sentence are referred to in this prospectus as “Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses.” To achieve these expense caps, BlackRock has agreed to waive and/or reimburse fees or expenses if these operating expenses exceed a certain limit.

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With respect to Master Small Cap Index Series, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses to the amount noted in the table below.

	Contractual Cap ¹ on Total Annual Fund Operating Expenses ² (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses)
Master Small Cap Index Series	0.07%

¹	The contractual cap is in effect through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series.

²	As a percentage of average daily net assets.

BlackRock, as administrator for Russell 2000 Small-Cap Index Fund and investment manager for MSCI EAFE International Index Fund, has contractually agreed to waive and/or reimburse fees and/or expenses in order to limit the Total Annual Fund Operating Expenses to the amounts noted in the table below.

	Contractual Caps ¹ on Total Annual Fund Operating Expenses ² (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses)
Fund
Russell 2000 Small-Cap Index Fund
Investor A Shares	0.37%
Institutional Shares	0.12%
MSCI EAFE International Index Fund
Investor A Shares	0.37%
Institutional Shares	0.12%

¹	The contractual caps are in effect through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the applicable Fund.

²	As a percentage of average daily net assets.

The amount of the contractual waivers and/or reimbursements of fees and expenses made pursuant to the contractual caps on net expenses will be reduced by the amount of the affiliated money market fund waiver.

BlackRock has entered into separate sub-advisory agreements (each, a “Sub-Advisory Agreement”) with BFA, with respect to Master Small Cap Index Series and MSCI EAFE International Index Fund, under which BlackRock pays BFA for services it provides for that portion of the Fund or Series, as applicable, for which BFA acts as sub-advisor under each Sub-Advisory Agreement a fee equal to a percentage of the management fee paid to BlackRock under the applicable Management Agreement.

A discussion of the basis for the approvals by the Board of Directors of the Corporation, with respect to Russell 2000 Small-Cap Index Fund, and the Board of Directors of the Master LLC, with respect to the Series, of the applicable Management Agreement and the applicable Sub-Advisory Agreement is included in the semi-annual shareholder report of Russell 2000 Small-Cap Index Fund for the period ended June 30, 2017. A discussion of the basis for the approval by the Board of Directors of the Corporation, with respect to MSCI EAFE International Index Fund, of the applicable Management Agreement and the applicable Sub-Advisory Agreement, is included in the annual shareholder report for MSCI EAFE International Index Fund for the period ended June 30, 2017.

From time to time, a manager, analyst, or other employee of BlackRock or its affiliates may express views regarding a particular asset class, company, security, industry, or market sector. The views expressed by any such person are the views of only that individual as of the time expressed and do not necessarily represent the views of BlackRock or any other person within the BlackRock organization. Any such views are subject to change at any time based upon market or other conditions and BlackRock disclaims any responsibility to update such views. These views may not be relied on as investment advice and, because investment decisions for the Funds are based on numerous factors, may not be relied on as an indication of trading intent on behalf of the Funds.

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Legal Proceedings. On May 27, 2014, certain purported investors in the BlackRock Global Allocation Fund, Inc. (“Global Allocation”) and the BlackRock Equity Dividend Fund (“Equity Dividend”) filed a consolidated complaint (the “Consolidated Complaint”) in the United States District Court for the District of New Jersey against BlackRock Advisors, LLC, BlackRock Investment Management, LLC and BlackRock International Limited (collectively, the “Defendants”) under the caption In re BlackRock Mutual Funds Advisory Fee Litigation . The Consolidated Complaint, which purports to be brought derivatively on behalf of Global Allocation and Equity Dividend, alleges that the Defendants violated Section 36(b) of the Investment Company Act by receiving allegedly excessive investment advisory fees from Global Allocation and Equity Dividend. The Consolidated Complaint seeks, among other things, to recover on behalf of Global Allocation and Equity Dividend all allegedly excessive advisory fees received by the Defendants in the period beginning one year prior to the filing of the lawsuit and ending on the date of judgment, along with purported lost investment returns on those amounts, plus interest. The Defendants believe the claims in the Consolidated Complaint are without merit and intend to vigorously defend the action.

Portfolio Manager Information

Information regarding the portfolio managers of Master Small Cap Index Series and MSCI EAFE International Index Fund is set forth below. Further information regarding the portfolio managers, including other accounts managed, compensation, ownership of Fund shares, and possible conflicts of interest, is available in the Corporation’s SAI.

Master Small Cap Index Series and MSCI EAFE International Index Fund are managed by a team of financial professionals. Information about the portfolio managers is provided below.

Portfolio Manager	Primary Role	Since	Title and Recent Biography
Alan Mason	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2014	Managing Director of BlackRock, Inc. since 2009; Managing Director of Barclays Global Investors (“BGI”) from 2008 to 2009; Principal of BGI from 1996 to 2008.
Greg Savage, CFA	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2012	Managing Director of BlackRock, Inc. since 2010; Director of BlackRock, Inc. in 2009; Principal of BGI from 2007 to 2009; Associate of BGI from 1999 to 2007.
Jennifer Hsui, CFA	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2016	Managing Director of BlackRock, Inc. since 2011; Director of BlackRock, Inc. from 2009 to 2011; Principal of BGI from 2006 to 2009.
Creighton Jue, CFA	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2016	Managing Director of BlackRock, Inc. since 2011; Director of BlackRock, Inc. from 2009 to 2011; Principal of BGI from 2000 to 2009.
Rachel Aguirre	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2016	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2012 to 2017; Vice President of BlackRock, Inc. from 2009 to 2011; Principal and Portfolio Manager of BGI from 2005 to 2009.

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Conflicts of Interest

The investment activities of BlackRock and its affiliates (including BlackRock, Inc. and PNC and their affiliates, directors, partners, trustees, managing members, officers and employees (collectively, the “Affiliates”)) in the management of, or their interest in, their own accounts and other accounts they manage, may present conflicts of interest that could disadvantage the Funds and their shareholders.

BlackRock and its Affiliates provide investment management services to other funds and discretionary managed accounts that follow investment programs similar to those of the Funds. BlackRock and its Affiliates are involved worldwide with a broad spectrum of financial services and asset management activities and may engage in the ordinary course of business in activities in which their interests or the interests of their clients may conflict with those of the Funds. One or more Affiliates act or may act as an investor, investment banker, research provider, investment manager, commodity pool operator, commodity trading advisor, financier, underwriter, adviser, market maker, trader, prime broker, lender, index provider, agent and principal, and have other direct and indirect interests in securities, currencies, commodities, derivatives and other instruments in which the Funds may directly or indirectly invest. Thus, it is likely that the Funds will have multiple business relationships with and will invest in, engage in transactions with, make voting decisions with respect to, or obtain services from, entities for which an Affiliate performs or seeks to perform investment banking or other services. Specifically, the Funds may invest in securities of, or engage in other transactions with, companies with which an Affiliate has developed or is trying to develop investment banking relationships or in which an Affiliate has significant debt or equity investments or other interests. The Funds also may invest in securities of, or engage in other transactions with, companies for which an Affiliate provides or may in the future provide research coverage. An Affiliate may have business relationships with, and purchase, or distribute or sell services or products from or to, distributors, consultants or others who recommend the Funds or who engage in transactions with or for the Funds, and may receive compensation for such services. The Funds may also make brokerage and other payments to Affiliates in connection with the Funds’ portfolio investment transactions. An Affiliate may engage in proprietary trading and advise accounts and funds that have investment objectives similar to those of the Funds and/or that engage in and compete for transactions in the same types of securities, currencies and other instruments as the Funds. This may include transactions in securities issued by other open-end and closed-end investment companies (which may include investment companies that are affiliated with the Funds and BlackRock, to the extent permitted under the Investment Company Act). The trading activities of these Affiliates are carried out without reference to positions held directly or indirectly by the Funds and may result in an Affiliate having positions in certain securities that are senior or junior to, or have interests different from or adverse to, the securities that are owned by the Funds.

No Affiliate is under any obligation to share any investment opportunity, idea or strategy with the Funds. As a result, an Affiliate may compete with the Funds for appropriate investment opportunities. The results of the Funds’ investment activities, therefore, may differ from those of an Affiliate and of other accounts managed by an Affiliate, and it is possible that the Funds could sustain losses during periods in which one or more Affiliates and other accounts achieve profits on their trading for proprietary or other accounts. The opposite result is also possible.

In addition, the Funds may, from time to time, enter into transactions in which an Affiliate or its other clients have an adverse interest. Furthermore, transactions undertaken by Affiliate-advised clients may adversely impact the Funds. Transactions by one or more Affiliate-advised clients or BlackRock may have the effect of diluting or otherwise disadvantaging the values, prices or investment strategies of the Funds. The Funds’ activities may be limited because of regulatory restrictions applicable to one or more Affiliates and/or their internal policies designed to comply with such restrictions.

Under a securities lending program approved by the Master LLC’s and Corporation’s Board of Directors, the Master LLC, on behalf of Master Small Cap Index Series, and the Corporation, on behalf of MSCI EAFE International Index Fund, has retained BlackRock Institutional Trust Company, N.A., an Affiliate of BlackRock, to serve as the securities lending agent for Master Small Cap Index Series and MSCI EAFE International Index Fund to the extent that Master Small Cap Index Series or MSCI EAFE International Index Fund participates in the securities lending program. For these services, the lending agent will receive a fee from Master Small Cap Index Series or MSCI EAFE International Index Fund, as applicable, including a fee based on the returns earned on Master Small Cap Index Series’ or MSCI EAFE International Index Fund’s investment of the cash received as collateral for the loaned securities. In addition, one or more Affiliates may be among the entities to which Master Small Cap Index Series or MSCI EAFE International Index Fund may lend its portfolio securities under the securities lending program.

The activities of Affiliates may give rise to other conflicts of interest that could disadvantage the Funds and their shareholders. BlackRock has adopted policies and procedures designed to address these potential conflicts of interest. See the SAI for further information.

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Valuation of Fund Investments

When you buy shares, you pay the net asset value, plus any applicable sales charge. This is the offering price. Shares are also redeemed at their net asset value, minus any applicable deferred sales charge or redemption fee. Each Fund calculates the net asset value of each class of its shares each day the NYSE is open, generally as of the close of regular trading hours on the NYSE, based on prices at the time of closing. The NYSE generally closes at 4:00 p.m. (Eastern time). The net asset value used in determining your share price is the next one calculated after your purchase or redemption order is received.

Equity securities and other instruments for which market quotations are readily available are valued at market value, which is generally determined using the last reported closing price or, if a reported closing price is not available, the last traded price on the exchange or market on which the security or instrument is primarily traded at the time of valuation. Each Fund values fixed-income portfolio securities and non-exchange traded derivatives using last available bid prices or current market quotations provided by dealers or prices (including evaluated prices) supplied by the Fund’s approved independent third-party pricing services, each in accordance with valuation procedures approved by the Board. Pricing services may use matrix pricing or valuation models that utilize certain inputs and assumptions to derive values. Pricing services generally value fixed-income securities assuming orderly transactions of institutional round lot size, but the Fund may hold or transact in such securities in smaller, odd lot sizes. Odd lots may trade at lower prices than institutional round lots. Short-term debt securities with remaining maturities of 60 days or less may be valued on the basis of amortized cost.

Foreign currency exchange rates are generally determined as of the close of business on the NYSE. Foreign securities owned by a Fund may trade on weekends or other days when a Fund does not price its shares. As a result, a Fund’s net asset value may change on days when you will not be able to purchase or redeem a Fund’s shares.

Generally, trading in foreign securities, U.S. Government securities, money market instruments and certain fixed-income securities is substantially completed each day at various times prior to the close of business on the NYSE. The values of such securities used in computing the net asset value of a Fund’s shares are determined as of such times.

When market quotations are not readily available or are not believed by BlackRock to be reliable, a Fund’s investments are valued at fair value. Fair value determinations are made by BlackRock in accordance with procedures approved by the Board. BlackRock may conclude that a market quotation is not readily available or is unreliable if a security or other asset or liability does not have a price source due to its lack of liquidity, if BlackRock believes a market quotation from a broker-dealer or other source is unreliable, where the security or other asset or other liability is thinly traded (e.g., municipal securities, certain small cap and emerging growth companies, and certain non-U.S. securities) or where there is a significant event subsequent to the most recent market quotation. For this purpose, a “significant event” is deemed to occur if BlackRock determines, in its business judgment prior to or at the time of pricing a Fund’s assets or liabilities, that it is likely that the event will cause a material change to the last closing market price of one or more assets or liabilities held by the Fund. For instance, significant events may occur between the foreign market close and the close of business on the NYSE that may not be reflected in the computation of a Fund’s net assets. If such event occurs, those instruments may be fair valued. Similarly, foreign securities whose values are affected by volatility that occurs in U.S. markets on a trading day after the close of foreign securities markets may be fair valued.

For certain foreign securities, a third-party vendor supplies evaluated, systematic fair value pricing based upon the movement of a proprietary multi-factor model after the relevant foreign markets have closed. This systematic fair value pricing methodology is designed to correlate the prices of foreign securities following the close of the local markets to the price that might have prevailed as of a Fund’s pricing time.

Fair value represents a good faith approximation of the value of a security. The fair value of one or more securities may not, in retrospect, be the price at which those assets could have been sold during the period in which the particular fair values were used in determining a Fund’s net asset value.

The Funds may accept orders from certain authorized Financial Intermediaries or their designees. The Funds will be deemed to receive an order when accepted by the Financial Intermediary or designee, and the order will receive the net asset value next computed by the Fund after such acceptance. If the payment for a purchase order is not made by a designated later time, the order will be canceled and the Financial Intermediary could be held liable for any losses.

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Dividends, Distributions and Taxes

BUYING A DIVIDEND

Unless your investment is in a tax-deferred account, you may want to avoid buying shares shortly before each Fund pays a dividend. The reason? If you buy shares when a Fund has declared but not yet distributed ordinary income or capital gains, you will pay the full price for the shares and then receive a portion of the price back in the form of a taxable dividend. Before investing you may want to consult your tax adviser.

Each Fund will distribute net investment income, if any, and net realized capital gains, if any, at least annually. Each Fund may also pay a special distribution at the end of the calendar year to comply with federal tax requirements. Dividends may be reinvested automatically in shares of each Fund at net asset value without a sales charge or may be taken in cash. If you would like to receive dividends in cash, contact your Financial Intermediary or the applicable Fund. Although this cannot be predicted with any certainty, each Fund anticipates that a significant amount of its dividends, if any, will consist of capital gains. Capital gains may be taxable to you at different rates depending on how long the Fund held the assets sold.

You will pay tax on dividends from a Fund whether you receive them in cash or additional shares. If you redeem Fund shares or exchange them for shares of another fund, you generally will be treated as having sold your shares and any gain on the transaction may be subject to tax. Fund distributions derived from qualified dividend income, which consists of dividends received from U.S. corporations and qualifying foreign corporations, and from long-term capital gains are eligible for taxation at a maximum rate of 15% or 20% for individuals, depending on whether their income exceeds certain threshold amounts, which are adjusted annually for inflation.

A 3.8% Medicare tax is imposed on the net investment income (which includes, but is not limited to, interest, dividends and net gain from investments) of U.S. individuals with income exceeding $200,000, or $250,000 if married filing jointly, and of trusts and estates.

Your dividends and redemption proceeds will be subject to backup withholding tax if you have not provided a taxpayer identification number or social security number or the number you have provided is incorrect.

If you are neither a tax resident nor a citizen of the United States or if you are a foreign entity (other than a pass-through entity to the extent owned by U.S. persons), a Fund’s ordinary income dividends will generally be subject to a 30% U.S. withholding tax, unless a lower treaty rate applies. However, certain distributions reported by a Fund as capital gain dividends, interest-related dividends or short-term capital gain dividends and paid to a foreign shareholder may be eligible for an exemption from U.S. withholding tax.

Separately, a 30% withholding tax is currently imposed on U.S.-source dividends, interest and other income items and will be imposed on proceeds from the sale, redemption or disposition of property producing U.S.-source dividends and interest paid after December 31, 2018, to (i) certain foreign financial institutions and investment funds, and (ii) certain other foreign entities. To avoid withholding, foreign financial institutions and investment funds will generally either need to (a) collect and report to the IRS detailed information identifying their U.S. accounts and U.S. account holders, comply with due diligence procedures for identifying U.S. accounts and withhold tax on certain payments made to noncomplying foreign entities and account holders or (b) if an intergovernmental agreement is entered into and implementing legislation is adopted, comply with the agreement and legislation. Other foreign entities will generally either need to provide detailed information identifying each substantial U.S. owner or certify there are no such owners.

This section summarizes some of the consequences under current federal tax law of an investment in a Fund. It is not a substitute for individualized tax advice. Consult your tax adviser about the potential tax consequences of an investment in a Fund under all applicable tax laws.

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Financial Highlights

The financial highlights tables are intended to help investors understand each Fund’s financial performance of the shares of each Fund for the past five years. Certain information reflects the financial results for a single share of the Fund. The total returns in the tables represent the rate of return that an investor would have earned (or lost) on an investment in the shares of the Fund, assuming reinvestment of all dividends and/or distributions. The information has been audited by Deloitte & Touche LLP, whose report, along with each Fund’s financial statements, are included in the respective Fund’s annual report. You may obtain copies of the annual report, at no cost, by calling (800) 441-7762 (toll-free) from 8:00 a.m. to 6:00 p.m. (Eastern time) on any business day.

For iShares MSCI EAFE International Index Fund, the financial highlights for the periods prior to August 1, 2016 reflect the “master/feeder” structure in place during the periods shown and “Master International Index” in such financial highlights refers to Master International Index Series, a series of the Master LLC.

Russell 2000 Small-Cap Index Fund

	Institutional
	Year Ended December 31,
(For a share outstanding throughout each period)	2017	2016	2015	2014	2013
Net asset value, beginning of year	$ 17.76	$ 15.32	$ 16.60	$ 17.51	$ 12.99
Net investment income ^(a)	0.25	0.23	0.24	0.20	0.22
Net realized and unrealized gain (loss)	2.34	3.03	(0.97)	0.56	4.83
Net increase (decrease) from investment operations	2.59	3.26	(0.73)	0.76	5.05
Distributions: ^(b)
From net investment income	(0.21)	(0.22)	(0.14)	(0.26)	(0.19)
From net realized gain	(0.42)	(0.60)	(0.41)	(1.41)	(0.34)
Total distributions	(0.63)	(0.82)	(0.55)	(1.67)	(0.53)
Net asset value, end of year	$ 19.72	$ 17.76	$ 15.32	$ 16.60	$ 17.51
Total Return ^(c)
Based on net asset value	14.55%	21.33%	(4.43)%	4.81%	39.14%
Ratios to Average Net Assets ^(d)(e)
Total expenses	0.18%	0.19% ^(f)	0.22%	0.35%	0.51%
Total expenses after fees waived and/or reimbursed	0.11%	0.14% ^(f)	0.16%	0.23%	0.29%
Net investment income	1.36%	1.44% ^(f)	1.47%	1.17%	1.45%
Supplemental Data
Net assets, end of year (000)	$167,351	$229,491	$148,148	$46,988	$60,707
Portfolio turnover rate of the Series	30%	39%	37%	21%	22%

^(a)	Based on average shares outstanding.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Where applicable, assumes the reinvestment of distributions.
^(d)	Includes the Fund’s share of the Series’ allocated expenses and/or net investment income.
^(e)	Includes the Fund’s share of the Series’ allocated fees waived of less than 0.01%.
^(f)	Excludes expenses incurred indirectly of 0.01% as a result of the Series’ investments in underlying funds.

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Financial Highlights (continued)

Russell 2000 Small-Cap Index Fund (concluded)

	Investor A
	Year Ended December 31,
(For a share outstanding throughout each period)	2017	2016	2015	2014	2013
Net asset value, beginning of year	$ 17.78	$ 15.34	$ 16.61	$ 17.52	$ 13.01
Net investment income ^(a)	0.21	0.18	0.18	0.16	0.19
Net realized and unrealized gain (loss)	2.34	3.03	(0.95)	0.56	4.82
Net increase (decrease) from investment operations	2.55	3.21	(0.77)	0.72	5.01
Distributions: ^(b)
From net investment income	(0.17)	(0.17)	(0.09)	(0.22)	(0.16)
From net realized gain	(0.42)	(0.60)	(0.41)	(1.41)	(0.34)
Total distributions	(0.59)	(0.77)	(0.50)	(1.63)	(0.50)
Net asset value, end of year	$ 19.74	$ 17.78	$ 15.34	$ 16.61	$ 17.52
Total Return ^(c)
Based on net asset value	14.35%	21.04%	(4.66)%	4.54%	38.72%
Ratios to Average Net Assets ^(d)(e)
Total expenses	0.45%	0.49% ^(f)	0.53%	0.63%	0.77%
Total expenses after fees waived and/or reimbursed	0.37%	0.41% ^(f)	0.43%	0.48%	0.55%
Net investment income	1.13%	1.14% ^(f)	1.09%	0.95%	1.20%
Supplemental Data
Net assets, end of year (000)	$249,980	$116,722	$87,930	$83,859	$83,118
Portfolio turnover rate of the Series	30%	39%	37%	21%	22%

^(a)	Based on average shares outstanding.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Where applicable, assumes the reinvestment of distributions.
^(d)	Includes the Fund’s share of the Series’ allocated expenses and/or net investment income.
^(e)	Includes the Fund’s share of the Series’ allocated fees waived of less than 0.01%.
^(f)	Excludes expenses incurred indirectly of 0.01% as a result of the Series’ investments in underlying funds.

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Financial Highlights (continued)

MSCI EAFE International Index Fund

	Institutional
	Year Ended December 31,
(For a share outstanding throughout each period)	2017	2016	2015	2014	2013
Net asset value, beginning of year	$ 11.60	$ 11.81	$ 12.21	$ 13.11	$ 11.06
Net investment income ^(a)	0.39	0.28	0.34	0.24	0.32
Net realized and unrealized gain (loss)	2.53	(0.16)	(0.46)	(1.04)	2.04
Net increase (decrease) from investment operations	2.92	0.12	(0.12)	(0.80)	2.36
Distributions from net investment income ^(b)	(0.34)	(0.33)	(0.28)	(0.10)	(0.31)
Net asset value, end of year	$ 14.18	$ 11.60	$ 11.81	$ 12.21	$ 13.11
Total Return ^(c)
Based on net asset value	25.24%	0.99%	(0.91)%	(6.13)%	21.52%
Ratios to Average Net Assets
Total expenses	0.09%	0.15% ^(d)(e)	0.12% ^(d)(e)	0.16% ^(d)(e)	0.40% ^(d)(e)
Total expenses after fees waived and/or reimbursed and/or paid indirectly	0.09%	0.11% ^(d)(e)	0.09% ^(d)(e)	0.11% ^(d)(e)	0.35% ^(d)(e)
Net investment income	2.92%	2.44% ^(d)(e)	2.68% ^(d)(e)	1.91% ^(d)(e)	2.64% ^(d)(e)
Supplemental Data
Net assets, end of year (000)	$705,986	$649,763	$2,702,936	$1,764,794	$71,826
Portfolio turnover rate	23%	42% ^(f)	9% ^(g)	6% ^(g)	8% ^(g)

^(a)	Based on average shares outstanding.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Where applicable, assumes the reinvestment of distributions.
^(d)	Includes the Fund’s share of Master International Index’s allocated expenses and/or net investment income.
^(e)	Includes the Fund’s share of Master International Index’s allocated fees waived of less than 0.01%.
^(f)	Portfolio turnover rate includes transactions from Master International Index prior to August 1, 2016.
^(g)	Portfolio turnover rate of Master International Index.

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Financial Highlights (concluded)

MSCI EAFE International Index Fund (concluded)

	Investor A
	Year Ended December 31,
(For a share outstanding throughout each period)	2017	2016	2015	2014	2013
Net asset value, beginning of year	$ 11.54	$ 11.75	$ 12.12	$ 13.02	$ 10.99
Net investment income ^(a)	0.34	0.32	0.32	0.41	0.29
Net realized and unrealized gain (loss)	2.52	(0.23)	(0.46)	(1.25)	2.02
Net increase (decrease) from investment operations	2.86	0.09	(0.14)	(0.84)	2.31
Distributions from net investment income ^(b)	(0.31)	(0.30)	(0.23)	(0.06)	(0.28)
Net asset value, end of year	$ 14.09	$ 11.54	$ 11.75	$ 12.12	$ 13.02
Total Return ^(c)
Based on net asset value	24.84%	0.78%	(1.14)%	(6.45)%	21.20%
Ratios to Average Net Assets
Total expenses	0.36%	0.38% ^(d)(e)	0.42% ^(d)(e)	0.52% ^(d)(e)	0.69% ^(d)(e)
Total expenses after fees waived and/or reimbursed and/or paid indirectly	0.35%	0.37% ^(d)(e)	0.37% ^(d)(e)	0.43% ^(d)(e)	0.60% ^(d)(e)
Net investment income	2.60%	2.78% ^(d)(e)	2.54% ^(d)(e)	3.13% ^(d)(e)	2.41% ^(d)(e)
Supplemental Data
Net assets, end of year (000)	$373,846	$238,053	$168,008	$332,475	$308,624
Portfolio turnover rate	23%	42% ^(f)	9% ^(g)	6% ^(g)	8% ^(g)

^(a)	Based on average shares outstanding.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Where applicable, assumes the reinvestment of distributions.
^(d)	Includes the Fund’s share of Master International Index’s allocated expenses and/or net investment income.
^(e)	Includes the Fund’s share of Master International Index’s allocated fees waived of less than 0.01%.
^(f)	Portfolio turnover rate includes transactions from Master International Index prior to August 1, 2016.
^(g)	Portfolio turnover rate of Master International Index.

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General Information

Shareholder Documents

Electronic Access to Annual Reports, Semi-Annual Reports and Prospectuses

Electronic copies of most financial reports and prospectuses are available on BlackRock’s website. Shareholders can sign up for e-mail notifications of annual and semi-annual reports and prospectuses by enrolling in the Funds’ electronic delivery program. To enroll:

Shareholders Who Hold Accounts with Investment Advisers, Banks or Brokerages: Please contact your Financial Intermediary. Please note that not all investment advisers, banks or brokerages may offer this service.

Shareholders Who Hold Accounts Directly With BlackRock:

■	Access the BlackRock website at http://www.blackrock.com/edelivery; and
■	Log into your account.

Delivery of Shareholder Documents

The Funds deliver only one copy of shareholder documents, including prospectuses, shareholder reports and proxy statements, to shareholders with multiple accounts at the same address. This practice is known as “householding” and is intended to eliminate duplicate mailings and reduce expenses. Mailings of your shareholder documents may be householded indefinitely unless you instruct us otherwise. If you do not want the mailing of these documents to be combined with those for other members of your household, please contact your Fund at (800) 441-7762.

Certain Fund Policies

Anti-Money Laundering Requirements

Each Fund is subject to the USA PATRIOT Act (the “Patriot Act”). The Patriot Act is intended to prevent the use of the U.S. financial system in furtherance of money laundering, terrorism or other illicit activities. Pursuant to requirements under the Patriot Act, each Fund is required to obtain sufficient information from shareholders to enable it to form a reasonable belief that it knows the true identity of its shareholders. This information will be used to verify the identity of investors or, in some cases, the status of Financial Intermediaries. Such information may be verified using third-party sources. This information will be used only for compliance with the Patriot Act or other applicable laws, regulations and rules in connection with money laundering, terrorism or economic sanctions.

The Fund reserves the right to reject purchase orders from persons who have not submitted information sufficient to allow the Fund to verify their identity. The Fund also reserves the right to redeem any amounts in the Fund from persons whose identity it is unable to verify on a timely basis. It is each Fund’s policy to cooperate fully with appropriate regulators in any investigations conducted with respect to potential money laundering, terrorism or other illicit activities.

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, “Clients”) and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your Financial Intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our website.

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BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law, or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

Statement of Additional Information

If you would like further information about each Fund, including how each Fund invests, please see the SAI.

For a discussion of each Fund’s policies and procedures regarding the selective disclosure of its portfolio holdings, please see the SAI. The Funds make their top ten holdings available on a monthly basis at www.blackrock.com generally within 5 business days after the end of the month to which the information applies.

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Glossary

This glossary contains an explanation of some of the common terms used in this prospectus. For additional information about the Funds, please see the SAI.

Acquired Fund Fees and Expenses — fees and expenses charged by other investment companies in which a Fund invests a portion of its assets.

Administration Fee — a fee paid to the Administrator for providing administrative services to Russell 2000 Small-Cap Index Fund.

Annual Fund Operating Expenses — expenses that cover the costs of operating a Fund.

Distribution Fees — fees used to support a Fund’s marketing and distribution efforts, such as compensating Financial Intermediaries, advertising and promotion.

Management Fee — a fee paid to BlackRock for managing the Series or MSCI EAFE International Index Fund, as applicable.

Market-Weighted Index — an index in which the weighting of each security is based on its market capitalization. In a market-weighted index, changes in the price of a company with a large capitalization affect the level of the index more than changes in the price of a company with smaller market capitalization.

MSCI EAFE Index (Europe, Australasia, Far East) — an index designed to represent the performance of large- and mid-cap securities across 21 developed markets in Europe, Australasia and the Far East, excluding the U.S. and Canada. As of December 2017 it had more than 900 constituents and covered approximately 85% of the free float-adjusted market capitalization in each country.

Other Expenses — include accounting, administration, transfer agency, custody, professional and registration fees.

Russell 2000 ^® Index — a subset of the Russell 3000 ^® Index representing approximately 10% of the total market capitalization of that index. It includes approximately 2000 of the smallest securities based on a combination of their market cap and current index membership.

Service Fees — fees used to compensate Financial Intermediaries for certain shareholder servicing activities.

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For More Information

Funds and Service Providers

FUNDS

BlackRock Index Funds, Inc.
iShares Russell 2000 Small-Cap Index Fund
iShares MSCI EAFE International Index Fund
100 Bellevue Parkway
Wilmington, Delaware 19809

Written Correspondence:
P.O. Box 9819
Providence, Rhode Island 02940-8019

Overnight Mail:
4400 Computer Drive
Westborough, Massachusetts 01588

(800) 441-7762

MANAGER

BlackRock Advisors, LLC
100 Bellevue Parkway
Wilmington, Delaware 19809

ADMINISTRATOR
To iShares Russell 2000 Small-Cap Index Fund:

BlackRock Advisors, LLC
100 Bellevue Parkway
Wilmington, Delaware 19809

SUB-ADVISER

BlackRock Fund Advisors
400 Howard Street
San Francisco, California 94105

TRANSFER AGENT

BNY Mellon Investment Servicing (US) Inc.
301 Bellevue Parkway
Wilmington, Delaware 19809

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Deloitte & Touche LLP
200 Berkeley Street
Boston, Massachusetts 02116

ACCOUNTING SERVICES PROVIDER

State Street Bank and Trust Company
One Lincoln Street
Boston, Massachusetts 02111

DISTRIBUTOR

BlackRock Investments, LLC
40 East 52nd Street
New York, New York 10022

CUSTODIAN

State Street Bank and Trust Company
One Lincoln Street
Boston, Massachusetts 02111

COUNSEL

Sidley Austin LLP
787 Seventh Avenue
New York, New York 10019-6018

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Additional Information

For more information:
This prospectus contains important information you should know before investing, including information about risks. Please read it before you invest and keep it for future reference. More information about the Funds is available at no charge upon request. This information includes:

Annual/Semi-Annual Reports
These reports contain additional information about each of the Fund’s investments. The annual report describes each Fund’s performance, lists portfolio holdings, and discusses recent market conditions, economic trends and Fund investment strategies that significantly affected each Fund’s performance for the last fiscal year.

Statement of Additional Information
A Statement of Additional Information (“SAI”), dated April 30, 2018, has been filed with the Securities and Exchange Commission (“SEC”). The SAI, which includes additional information about each Fund, may be obtained free of charge, along with each Fund’s annual and semi-annual reports, by calling (800) 441-7762. The SAI, as supplemented from time to time, is incorporated by reference into this prospectus.

BlackRock Investor Services
Representatives are available to discuss account balance information, mutual fund prospectuses, literature, programs and services available. Hours: 8:00 a.m. to 6:00 p.m. (Eastern time), on any business day. Call: (800) 441-7762.

Purchases and Redemptions
Call your Financial Intermediary or BlackRock Investor Services at (800) 441-7762.

World Wide Web
General Fund information and specific Fund performance, including the SAI and annual/semi-annual reports, can be accessed free of charge at www.blackrock.com/prospectus. Mutual fund prospectuses and literature can also be requested via this website.

Written Correspondence
BlackRock Index Funds, Inc.
P.O. Box 9819
Providence, Rhode Island 02940

Overnight Mail
BlackRock Index Funds, Inc.
4400 Computer Drive
Westborough, Massachusetts 01588

Internal Wholesalers/Broker Dealer Support
Available on any business day to support investment professionals. Call: (800) 882-0052.

Portfolio Characteristics and Holdings
A description of each Fund’s policies and procedures related to disclosure of portfolio characteristics and holdings is available in the SAI.

For information about portfolio holdings and characteristics, BlackRock fund shareholders and prospective investors may call (800) 882-0052.

Securities and Exchange Commission
You may also view and copy public information about each Fund, including the SAI, by visiting the EDGAR database on the SEC’s website (http://www.sec.gov) or the SEC’s Public Reference Room in Washington, D.C. Copies of this information can be obtained, for a duplicating fee, by electronic request at the following e-mail address: publicinfo@sec.gov, or by writing to the Public Reference Room of the SEC, Washington, D.C. 20549. Information about obtaining documents on the SEC’s website without charge may be obtained by calling (800) SEC-0330.

You should rely only on the information contained in this prospectus. No one is authorized to provide you with information that is different from information contained in this prospectus.

The SEC has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

BLACKROCK INDEX FUNDS, INC.
INVESTMENT COMPANY ACT FILE # 811-7899

PRO-19003-INV-0418

APRIL 30, 2018

Prospectus

BlackRock Index Funds, Inc. | Class K Shares

►	iShares Russell 2000 Small-Cap Index Fund

Class K: BDBKX

►	iShares MSCI EAFE International Index Fund

Class K: BTMKX

This 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 has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

Not FDIC Insured • May Lose Value • No Bank Guarantee

Table of Contents

Fund Overview	Key facts and details about the Funds listed in this prospectus, including investment objectives, principal investment strategies, principal risk factors, fee and expense information and historical performance information
	Key Facts About iShares Russell 2000 Small-Cap Index Fund	3
	Key Facts About iShares MSCI EAFE International Index Fund	7

Details About the Funds	Information about how each Fund invests, including investment objectives, investment processes, principal strategies and risk factors
	How Each Fund Invests	12
	Investment Risks	15

Account Information	Information about account services, sales charges and waivers, shareholder transactions, and distribution and other payments
	Details About the Share Class	22
	How to Buy, Sell, Exchange and Transfer Shares	23
	Funds’ Rights	27
	Short-Term Trading Policy	28
	Master/Feeder Structure	29

Management of the Funds	Information about BlackRock and the Portfolio Managers
	BlackRock	30
	Portfolio Manager Information	32
	Conflicts of Interest	32
	Valuation of Fund Investments	33
	Dividends, Distributions and Taxes	35

Financial Highlights	Financial Performance of the Funds	36

General Information	Shareholder Documents	38
	Certain Fund Policies	38
	Statement of Additional Information	39

Glossary	Glossary of Investment Terms	40

For More Information	Funds and Service Providers	Inside Back Cover
	Additional Information	Back Cover

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Fund Overview

Key Facts About iShares Russell 2000 Small-Cap Index Fund

Investment Objective

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold Class K Shares of Russell 2000 Small-Cap Index Fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) ¹		Class K Shares
Management Fee ^1,2		0.01%
Distribution and/or Service (12b-1) Fees		None
Other Expenses		0.13%
Administration Fees	0.04%
Miscellaneous Other Expenses	0.09%
Total Annual Fund Operating Expenses		0.14%
Fee Waivers and/or Expense Reimbursements ^2,3		(0.07)%
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements ^2,3		0.07%

As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 30, BlackRock Advisors, LLC (“BlackRock”) has contractually agreed to waive the management fee with respect to any portion of the Series’ assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series.

As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 30, BlackRock has contractually agreed to waive and/or reimburse fees and/or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of Russell 2000 Small-Cap Index Fund (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) as a percentage of average daily net assets to 0.07% (for Class K Shares) through April 30, 2019. In addition to the contractual waiver with respect to the Fund, BlackRock 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 of the Series (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Series expenses) to 0.07% of average daily net assets through April 30, 2019. These contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or of the Master LLC, as applicable, or by a vote of a majority of the outstanding voting securities of the Fund or the Series, as applicable.

Example:

	1 Year	3 Years	5 Years	10 Years
Class K Shares	$7	$38	$72	$172

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Portfolio Turnover:

Principal Investment Strategies of the Fund

Principal Risks of Investing in the Fund

■	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.
■	Index Fund Risk — An index fund has operating and other expenses while an index does not. As a result, while the Fund will attempt to track the Russell 2000 as closely as possible, it will tend to underperform the index to some degree over time. If an index fund is properly correlated to its stated index, the fund will perform poorly when the index performs poorly.

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Performance Information

Class K Shares of Russell 2000 Small-Cap Index Fund commenced operations on March 31, 2011. As a result, the returns in the chart and table for Class K Shares, prior to their commencement of operations on March 31, 2011, show the performance of the Fund’s Institutional Shares. The performance of the Fund’s Class K Shares would be substantially similar to Institutional Shares because Class K Shares and Institutional Shares invest in the same portfolio of securities and performance would only differ to the extent that Class K Shares and Institutional Shares have different expenses. The actual returns of Class K Shares would have been higher than those of the Institutional Shares because Class K Shares have lower expenses than the Institutional Shares.

Class K Shares

ANNUAL TOTAL RETURNS

Russell 2000 Small-Cap Index Fund
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 20.61% (quarter ended June 30, 2009) and the lowest return for a quarter was -26.30% (quarter ended December 31, 2008).

As of 12/31/17 Average Annual Total Returns	1 Year	5 Years	10 Years
iShares Russell 2000 Small-Cap Index Fund — Class K Shares
Return Before Taxes	14.69%	14.19%	8.62%
Return After Taxes on Distributions	13.63%	12.76%	7.44%
Return After Taxes on Distributions and Sale of Fund Shares	8.80%	11.04%	6.61%
Russell 2000 ^® Index (Reflects no deduction for fees, expenses or taxes)	14.65%	14.12%	8.71%

Investment Manager

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Portfolio Managers

Name	Portfolio Manager of the Series Since	Title
Alan Mason	2014	Managing Director of BlackRock, Inc.
Greg Savage, CFA	2012	Managing Director of BlackRock, Inc.
Jennifer Hsui, CFA	2016	Managing Director of BlackRock, Inc.
Creighton Jue, CFA	2016	Managing Director of BlackRock, Inc.
Rachel Aguirre	2016	Managing Director of BlackRock, Inc.

Purchase and Sale of Fund Shares

Class K Shares of the Fund are available only to (i) certain employee benefit plans, such as health savings accounts, and certain employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs and SARSEPs) (collectively, “Employer-Sponsored Retirement Plans”), (ii) collective trust funds, investment companies and other pooled investment vehicles, each of which may purchase shares of the Fund through a Financial Intermediary (as defined below) that has entered into an agreement with the Fund’s distributor to purchase such shares, (iii) “Institutional Investors,” which include, but are not limited to, endowments, foundations, family offices, banks and bank trusts, local, city, and state governmental institutions, corporations and insurance company separate accounts, 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, (iv) fee-based advisory platforms of a Financial Intermediary that (a) has specifically acknowledged in a written agreement with the Distributor and/or its affiliate(s) that the Financial Intermediary shall offer such shares to fee-based advisory clients through an omnibus account held at the Fund or (b) transacts in the Fund’s shares through another intermediary that has executed such an agreement and (v) any other investors who met the eligibility criteria for BlackRock Shares or Class K Shares prior to August 15, 2016 and have continually held Class K Shares of the Fund in the same account since August 15, 2016.

You may purchase or redeem shares of the Fund each day the New York Stock Exchange is open. Purchase orders may also be placed by calling (800) 537-4942, by mail (c/o BlackRock Funds, P.O. Box 9819, Providence, Rhode Island 02940-8019), or online at www.blackrock.com. Institutional Investors are subject to a $5 million minimum initial investment requirement. Other investors, including Employer-Sponsored Retirement Plans, have no minimum initial investment requirement. There is no minimum investment amount for additional purchases.

Tax Information

Different income tax rules apply depending on whether you are invested through a qualified tax-exempt plan described in section 401(a) of the Internal Revenue Code of 1986, as amended. If you are invested through such a plan (and Fund shares are not “debt-financed property” to the plan), then the dividends paid by the Fund and the gain realized from a redemption or exchange of Fund shares will generally not be subject to U.S. federal income taxes until you withdraw or receive distributions from the plan. If you are not invested through such a plan, then the Fund’s dividends and gain from a redemption or exchange may be subject to U.S. federal income taxes and may be taxed as ordinary income or capital gains, unless you are a tax-exempt investor.

Payments to Broker/Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a financial professional or selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock, The PNC Financial Services Group, Inc. and their respective affiliates) (each 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.

Class K Shares are only available through a Financial Intermediary if the Financial Intermediary will not receive from Fund assets, or the Fund’s distributor’s or an affiliate’s resources, any commission payments, shareholder servicing fees (including sub-transfer agent and networking fees), or distribution fees (including Rule 12b-1 fees) with respect to assets invested in Class K Shares. Ask your individual financial professional or visit your Financial Intermediary’s website for more information.

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Fund Overview

Key Facts About iShares MSCI EAFE International Index Fund

Investment Objective

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold Class K Shares of MSCI EAFE International Index Fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)		Class K Shares
Management Fee ¹		0.01%
Distribution and/or Service (12b-1) Fees		None
Other Expenses		0.05%
Total Annual Fund Operating Expenses		0.06%
Fee Waivers and/or Expense Reimbursements ^1,2		—
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements ^1,2		0.06%

As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 30, BlackRock Advisors, LLC (“BlackRock”) has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the Fund.

Example:

	1 Year	3 Years	5 Years	10 Years
Class K Shares	$6	$19	$34	$77

Portfolio Turnover:

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Principal Investment Strategies of the Fund

Principal Risks of Investing in the Fund

■	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.
■	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.
■	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. These events may spread to other countries in Europe. These events may affect the value and liquidity of certain of the Fund’s investments.

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Performance Information

Class K Shares of MSCI EAFE International Index Fund commenced operations on March 31, 2011. As a result, the returns in the chart and table for Class K Shares, prior to their commencement of operations on March 31, 2011, show the performance of the Fund’s Institutional Shares. The performance of the Fund’s Class K Shares would be substantially similar to Institutional Shares because Class K Shares and Institutional Shares invest in the same portfolio of securities and performance would only differ to the extent that Class K Shares and Institutional Shares have different expenses. The actual returns of Class K Shares would have been higher than those of the Institutional Shares because Class K Shares have lower expenses than the Institutional Shares.

The information shows 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 MSCI EAFE 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. The table includes all applicable fees. If BlackRock 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 www.blackrock.com or can be obtained by phone at (800) 882-0052.

Class K Shares

ANNUAL TOTAL RETURNS

MSCI EAFE International Index Fund
As of 12/31

During the ten-year period shown in the bar chart, the highest return for a quarter was 25.27% (quarter ended June 30, 2009) and the lowest return for a quarter was -20.05% (quarter ended September 30, 2011).

As of 12/31/17 Average Annual Total Returns	1 Year	5 Years	10 Years
iShares MSCI EAFE International Index Fund — Class K Shares
Return Before Taxes	25.17%	7.44%	1.68%
Return After Taxes on Distributions	24.49%	7.02%	0.92%
Return After Taxes on Distributions and Sale of Fund Shares	14.87%	5.92%	1.05%
MSCI EAFE Index (Europe, Australasia, Far East) (Reflects no deduction for fees, expenses or taxes)	25.03%	7.90%	1.94%

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Investment Manager

Portfolio Managers

Name	Portfolio Manager of the Fund Since	Title
Alan Mason	2014	Managing Director of BlackRock, Inc.
Greg Savage, CFA	2012	Managing Director of BlackRock, Inc.
Jennifer Hsui, CFA	2016	Managing Director of BlackRock, Inc.
Creighton Jue, CFA	2016	Managing Director of BlackRock, Inc.
Rachel Aguirre	2016	Managing Director of BlackRock, Inc.

Purchase and Sale of Fund Shares

Tax Information

Payments to Broker/Dealers and Other Financial Intermediaries

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Details About the Funds

Included in this prospectus are sections that tell you about buying and selling shares, management information, shareholder features of iShares Russell 2000 Small-Cap Index Fund (formerly known as BlackRock Small Cap Index Fund) (“Russell 2000 Small-Cap Index Fund”) and iShares MSCI EAFE International Index Fund (formerly known as BlackRock International Index Fund) (“MSCI EAFE International Index Fund”) (each a “Fund” and collectively the “Funds”), each a series of BlackRock Index Funds, Inc. (the “Corporation”), and your rights as a shareholder. Russell 2000 Small-Cap Index Fund is a “feeder” fund that invests all of its assets in Master Small Cap Index Series (the “Series”) of Quantitative Master Series LLC (the “Master LLC”), a mutual fund that has the same objective and strategies as Russell 2000 Small-Cap Index Fund. All of Russell 2000 Small-Cap Index Fund’s investments will be made at the Master LLC level. This structure is sometimes called a “master/ feeder” structure. Russell 2000 Small-Cap Index Fund’s investment results will correspond directly to the investment results of the Series. For simplicity, this prospectus uses the name “Russell 2000 Small-Cap Index Fund” or the term “Fund,” if applicable, to include the Series.

How Each Fund Invests

Investment Process

Russell 2000 Small-Cap Index Fund

Investment Objective

Principal Investment Strategies

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capitalizations, industry weightings and other fundamental characteristics of the stocks and derivative instruments in its portfolio are similar to the Russell 2000 as a whole.

ABOUT THE PORTFOLIO MANAGEMENT TEAM OF MASTER SMALL CAP INDEX SERIES

MSCI EAFE International Index Fund

Investment Objective

Principal Investment Strategies

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ABOUT THE PORTFOLIO MANAGEMENT TEAM OF MSCI EAFE INTERNATIONAL INDEX FUND

Other Strategies Applicable to the Funds

In addition to the principal strategies discussed above, each Fund may also invest or engage in the following investments/strategies:

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■	“New Issues” (Russell 2000 Small-Cap Index Fund) — The Fund has the ability to invest in “new issues.” “New issues” are initial public offerings (“IPOs”) of equity securities.

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■	Repurchase Agreements — Each Fund may enter into certain types of repurchase agreements. Under a repurchase agreement, the seller agrees to repurchase a security at a mutually agreed-upon time and price.
■	Securities Lending — Each Fund may lend securities with a value up to 33 ¹ ⁄ 3 % of its total assets to financial institutions that provide cash or securities issued or guaranteed by the U.S. Government as collateral.
■	Short-Term Money Market Instruments — Each Fund may invest in short-term money market instruments as cash reserves to maintain liquidity. These instruments may include obligations of the U.S. Government, its agencies or instrumentalities, highly rated bonds or comparable unrated bonds, commercial paper, bank obligations, repurchase agreements and commingled short-term liquidity funds. To the extent a Fund invests in short-term money market instruments, it will generally also invest in futures or other derivatives in order to maintain full exposure to the index at all times.

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Investment Risks

Principal Risks of Investing in the Funds

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	Generally, when the U.S. dollar rises in value against a foreign currency, a security denominated in that currency loses value because the currency is worth fewer U.S. dollars. Conversely, when the U.S. dollar decreases in value against a foreign currency, a security denominated in that currency gains value because the currency is worth more U.S. dollars. This risk, generally known as “currency risk,” means that a strong U.S. dollar will reduce returns for U.S. investors while a weak U.S. dollar will increase those returns.
	Foreign Economy Risk — 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. Certain foreign economies may rely heavily on particular industries or foreign capital and are more vulnerable to diplomatic developments, the imposition of economic sanctions against a particular country or countries, changes in international trading patterns, trade barriers and other protectionist or retaliatory measures. Investments in foreign markets may also be adversely affected by governmental actions such as the imposition of capital controls, nationalization of companies or industries, expropriation of assets or the imposition of punitive taxes. In addition, the governments of certain countries may prohibit or impose substantial restrictions on foreign investments in their capital markets or in certain industries. Any of these actions could severely affect securities prices or impair the Fund’s ability to purchase or sell foreign securities or transfer the Fund’s assets or income back into the United States, or otherwise adversely affect the Fund’s operations.
	Other potential foreign market risks include foreign exchange controls, difficulties in pricing securities, defaults on foreign government securities, difficulties in enforcing legal judgments in foreign courts and political and social instability. Diplomatic and political developments, including rapid and adverse political changes, social instability, regional conflicts, terrorism and war, could affect the economies, industries and securities and currency markets, and the value of the Fund’s investments, in non-U.S. countries. These factors are extremely difficult, if not impossible, to predict and take into account with respect to the Fund’s investments.
	Governmental Supervision and Regulation/Accounting Standards — Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as such regulations exist in the United States. They also may not have laws to protect investors that are comparable to U.S. securities laws. For example, some foreign countries may have no laws or rules against insider trading. Insider trading occurs when a person buys or sells a company’s securities based on material non-public information about that company. In addition, some countries may have legal systems that may make it difficult for the Fund to vote proxies, exercise shareholder rights, and pursue legal remedies with respect to its foreign investments. Accounting standards in other countries are not necessarily the same as in the United States. If the accounting standards in another country do not require as much detail as U.S. accounting standards, it may be harder for Fund management to completely and accurately determine a company’s financial condition.
	Settlement Risk — Settlement and clearance procedures in certain foreign markets differ significantly from those in the United States. Foreign settlement and clearance procedures and trade regulations also may involve certain risks (such as delays in payment for or delivery of securities) not typically associated with the settlement of U.S. investments.
	At times, settlements in certain foreign countries have not kept pace with the number of securities transactions. These problems may make it difficult for the Fund to carry out transactions. If the Fund cannot settle or is delayed in settling a purchase of securities, it may miss attractive investment opportunities and certain of its assets may be uninvested with no return earned thereon for some period. If the Fund cannot settle or is delayed in settling a sale of securities, it may lose money if the value of the security then declines or, if it has contracted to sell the security to another party, the Fund could be liable for any losses incurred.
	European Economic Risk — 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. These events may spread to other countries in Europe. These events may affect the value and liquidity of certain of the Fund’s investments.
	Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. In addition, the United Kingdom has voted to withdraw from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching.
■	Index Fund Risk — An index fund has operating and other expenses while an index does not. As a result, while the Fund will attempt to track the applicable index as closely as possible, it will tend to underperform the index to some

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degree over time. If an index fund is properly correlated to its stated index, the fund will perform poorly when the index performs poorly.

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Other Risks of Investing in the Funds

Each Fund may also be subject to certain other risks associated with its investments and investment strategies, including:

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■	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:
	Volatility 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 with the overall securities markets.
	Counterparty Risk — Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation.
	Market and Liquidity Risk — Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. 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. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund’s derivatives positions to lose value.
	Valuation Risk — 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 may also 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.
	Hedging Risk — When a derivative is used as a hedge against a position that the Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund’s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences noted below.
	Tax Risk — The federal income tax treatment of a derivative may not be as favorable as a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments. As a result, a larger portion of the Fund’s distributions may be treated as ordinary income rather than capital gains. In addition, certain derivatives are subject to mark-to-market or straddle provisions of the Internal Revenue Code. If such provisions are applicable, there could be an increase (or decrease) in the amount of taxable dividends paid by the Fund. In addition, the tax treatment of certain derivatives, such as swaps, is unsettled and may be subject to future legislation, regulation or administrative pronouncements issued by the Internal Revenue Service (“IRS”).

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Risks Specific to Certain Derivatives Used by the Fund

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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.

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■	“New Issues” Risk (Russell 2000 Small-Cap Index Fund) — “New issues” are IPOs of equity securities. Investments in companies that have recently gone public have the potential to produce substantial gains for the Fund. However, there is no assurance that the Fund will have access to profitable IPOs and therefore investors should not rely on these past gains as an indication of future performance. The investment performance of the Fund during periods when it is unable to invest significantly or at all in IPOs may be lower than during periods when the Fund is able to do so. In addition, as the Fund increases in size, the impact of IPOs on the Fund’s performance will generally decrease. Securities issued in IPOs are subject to many of the same risks as investing in companies with smaller market capitalizations. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO. When an IPO is brought to the market, availability may be limited and the Fund may not be able to buy any shares at the offering price, or, if it is able to buy shares, it may not be able to buy as many shares at the offering price as it would like.
■	Passive Investment Risk — Because BlackRock does not select individual companies in the index that the Fund tracks, the Fund may hold securities of companies that present risks that an investment adviser researching individual securities might seek to avoid.
■	REIT Investment Risk — In addition to the risks facing real estate-related securities, such as a decline in property values due to increasing vacancies, a decline in rents resulting from unanticipated economic, legal or technological developments or a decline in the price of securities of real estate companies due to a failure of borrowers to pay their loans or poor management, investments in REITs involve unique risks. REITs may have limited financial resources, may trade less frequently and in limited volume and may be more volatile than other securities. In addition, recently enacted tax legislation permits a direct REIT shareholder to claim a 20% “qualified business income” deduction for ordinary REIT dividends, but does not permit a regulated investment company to pass through to its shareholders the special character of this income. Ordinary REIT dividends received by the Fund and distributed to the Fund’s shareholders also will generally not constitute “qualified dividend income.“ Therefore, the tax rate applicable to that portion of the dividend income attributable to ordinary REIT dividends received by the Fund will be taxed at a higher rate than dividends eligible for special treatment.

■	Repurchase Agreements Risk — If the other party to a repurchase agreement 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 and the market value of the security declines, the Fund may lose money.
■	Securities Lending Risk — Securities lending involves the risk that the borrower may fail to return the securities in a timely manner or at all. As a result, the Fund may lose money and there may be a delay in recovering the loaned securities. The Fund could also lose money if it does not recover the securities and/or the value of the collateral falls, including the value of investments made with cash collateral. These events could trigger adverse tax consequences for the Fund.
■	Short Sales Risk — Because making short sales in securities that it does not own exposes the Fund to the risks associated with those securities, such short sales involve speculative exposure risk. The Fund will incur a loss as a result of a short sale if the price of the security increases between the date of the short sale and the date on which the Fund replaces the security sold short. The Fund will realize a gain if the security declines in price between those dates. As a result, if the Fund makes short sales in securities that increase in value, it will likely underperform similar funds that do not make short sales in securities they do not own. There can be no assurance that the Fund will be able to close out a short sale position at any particular time or at an acceptable price. Although the Fund’s gain is limited to the amount at which it sold a security short, its potential loss is limited only by the maximum attainable price of the security, less the price at which the security was sold. The Fund may also pay transaction costs and borrowing fees in connection with short sales.
■	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

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Account Information

Details About the Share Class

Each Fund currently offers multiple share classes (Class K Shares in this prospectus), each with its own expense structure, allowing you to invest in the way that best suits your needs. Each share class represents an ownership interest in the same investment portfolio of the particular Fund. When you choose your class of shares, you should consider the size of your investment and how long you plan to hold your shares. Only certain investors are eligible to buy Class K Shares. Either your financial professional or 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”) can help you determine whether you are eligible to buy Class K Shares.

Each Fund’s shares are distributed by BlackRock Investments, LLC (the “Distributor”), an affiliate of BlackRock.

The table below summarizes key features of Class K Shares of each Fund.

Class K Shares at a Glance


Availability	Available only to (i) employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs and SARSEPs) (“Employer-Sponsored Retirement Plans”), (ii) collective trust funds, investment companies and other pooled investment vehicles, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares, (iii) “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, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Distributor to purchase such shares, (iv) fee-based advisory platforms of a Financial Intermediary that (a) has specifically acknowledged in a written agreement with the Distributor and/or its affiliate(s) that the Financial Intermediary shall offer such shares to fee-based advisory clients through an omnibus account held at the Fund or (b) transacts in the Fund’s shares through another intermediary that has executed such an agreement and (v) any other investors who met the eligibility criteria for BlackRock Shares or Class K Shares prior to August 15, 2016 and have continually held Class K Shares of the Fund in the same account since August 15, 2016.
Minimum Investment	$5 million minimum initial investment for Institutional Investors. There is no minimum initial investment requirement for any Employer-Sponsored Retirement Plans or any other eligible investors other than Institutional Investors. There is no minimum investment amount for additional purchases.
Initial Sales Charge?	No. Entire purchase price is invested in shares of the Fund.
Deferred Sales Charge?	No.
Distribution and Service (12b-1) Fees?	No.
Redemption Fees?	No.

Each Fund the right to modify or waive the above-stated policies at any time.

When Class K Shares are purchased through a customer’s account in an Employer-Sponsored Retirement Plan through procedures established by the Employer-Sponsored Retirement Plan, confirmation of share purchases and redemptions will be sent to the Employer-Sponsored Retirement Plan. A customer’s ownership of shares will be recorded by the Employer-Sponsored Retirement Plan and reflected in the account statements provided by the Employer-Sponsored Retirement Plan to its participants.

If you purchased your shares through an Employer-Sponsored Retirement Plan and you transfer your investment from an Employer-Sponsored Retirement Plan to a type of account, such as an individual retirement account, that is not an eligible Class K Share investor in the Funds, you must liquidate your investment in Class K Shares of the Fund and

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purchase a share class of either a Fund or or another fund advised by BlackRock or its affiliates that is available for purchase by that type of account.

For investors not purchasing shares through an Employer-Sponsored Retirement Plan, please see below for information on how to buy, sell, exchange and transfer shares.

How to Buy, Sell, Exchange and Transfer Shares

The chart below and on the following pages summarizes how to buy, sell, exchange and transfer shares through your Financial Intermediary. If you are not purchasing shares through an Employer-Sponsored Retirement Plan, you may also buy, sell, exchange and transfer shares through BlackRock if your account is held directly with BlackRock. To learn more about buying, selling, exchanging or transferring shares through BlackRock, call (800) 537-4942. Because the selection of a mutual fund involves many considerations, your Financial Intermediary may help you with this decision.

With certain limited exceptions, the Funds are generally available only to investors residing in the United States and may not be distributed by a foreign Financial Intermediary. Under this policy, in order to accept new accounts or additional investments (including by way of exchange from another mutual fund sponsored and advised by BlackRock or its affiliates (a “BlackRock Fund”)) into existing accounts, a Fund generally requires that (i) a shareholder that is a natural person be a U.S. citizen or resident alien, in each case residing within the United States or a U.S. territory (including APO/FPO/DPO addresses), and have a valid U.S. taxpayer identification number, and (ii) a Financial Intermediary or a shareholder that is an entity be domiciled in the United States and have a valid U.S. taxpayer identification number or be domiciled in a U.S. territory and have a valid U.S. taxpayer identification number or IRS Form W-8. Any existing account that is updated to reflect a non-U.S. address will also be restricted from making additional investments.

Under certain circumstances, if no activity occurs in an account within a time period specified by state law, a shareholder’s shares in a Fund may be transferred to that state.

How to Buy Shares

	Your Choices	Important Information for You to Know
Initial Purchase	Determine the amount of your investment	There is no minimum initial investment for any Employer-Sponsored Retirement Plans or any other investors other than Institutional Investors. For Institutional Investors, there is a $5 million minimum initial investment for all accounts.
	Have your Financial Intermediary submit your purchase order	The price of your shares is based on the next calculation of the Fund’s net asset value after your order is placed. Any purchase orders placed prior to the close of business on the New York Stock Exchange (the “NYSE”) (generally 4:00 p.m. Eastern time) will be priced at the net asset value determined that day. Certain Financial Intermediaries, however, may require submission of orders prior to that time. Purchase orders placed after that time will be priced at the net asset value determined on the next business day. A broker-dealer or financial institution maintaining the account in which you hold shares may charge a separate account, service or transaction fee on the purchase or sale of Fund shares that would be in addition to the fees and expenses shown in the Fund’s “Fees and Expenses” table. The Fund may reject any order to buy shares and may suspend the sale of shares at any time. Certain Financial Intermediaries may charge a processing fee to confirm a purchase.
	Or contact BlackRock (for accounts held directly with BlackRock)	For investors not purchasing shares through an Employer-Sponsored Retirement Plan, to purchase shares directly from BlackRock, call (800) 537-4942 and request a new account application.

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	Your Choices	Important Information for You to Know
Add to Your Investment	Purchase additional shares	There is no minimum investment amount for additional purchases.
	Have your Financial Intermediary submit your purchase order for additional shares	To purchase additional shares, you may contact your Financial Intermediary or Employer-Sponsored Retirement Plan.
	Or contact BlackRock (for accounts held directly with BlackRock)	For investors not purchasing shares through an Employer-Sponsored Retirement Plan : Purchase by Telephone : Call the Fund at (800) 537-4942 and speak with one of our representatives. The Fund has the right to reject any telephone request for any reason. Purchase by Internet : You may purchase your shares, and view activity in your account, by logging onto the BlackRock website at www.blackrock.com. Purchases made on the Internet using the Automated Clearing House (“ACH”) will have a trade date that is the day after the purchase is made. Certain institutional clients’ purchase orders placed by wire prior to the close of business on the NYSE will be priced at the net asset value determined that day. Contact your Financial Intermediary or BlackRock for further information. Limits on amounts that may be purchased via Internet may vary. For additional information call BlackRock at (800) 537-4942. Please read the On-Line Services Disclosure Statement and User Agreement, the Terms and Conditions page and the Consent to Electronic Delivery Agreement (if you consent to electronic delivery), before attempting to transact online. The Fund employs reasonable procedures to confirm that transactions entered over the Internet are genuine. By entering into the User Agreement with the Fund in order to open an account through the website, the shareholder waives any right to reclaim any losses from the Fund or any of its affiliates, incurred through fraudulent activity.
	Acquire additional shares by reinvesting dividends and capital gains	All dividends and capital gains distributions are automatically reinvested without a sales charge. To make any changes to your dividend and/or capital gains distributions options, please call BlackRock at (800) 537-4942 (for investors who are not purchasing shares through an Employer-Sponsored Retirement Plan) or contact your Financial Intermediary.
How to Pay for Shares	Making payment for purchases	If you are purchasing shares through an Employer-Sponsored Retirement Plan, payment for an order must be made in Federal funds or other immediately available funds by the time specified by your Financial Intermediary, but in no event later than 4:00 p.m. (Eastern time) on the first business day following the receipt of the order. If payment is not received by this time, the order will be canceled and you and your Financial Intermediary will be responsible for any loss to the Fund. If you are not purchasing shares through an Employer-Sponsored Retirement Plan, payment for shares must normally be made in Federal funds or other immediately available funds by the time specified by your Financial Intermediary but in no event later than 4:00 p.m. (Eastern time) on the first business day following the receipt of the order. Payment may also, at the discretion of the Fund, be made in the form of securities that are permissible investments for the respective fund. If payment is not received by this time, the order will be canceled and you and your Financial Intermediary will be responsible for any loss to the Funds.

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How to Sell Shares

	Your Choices	Important Information for You to Know
Full or Partial Redemption of Shares	Have your Financial Intermediary submit your sales order	If you purchased shares through an Employer-Sponsored Retirement Plan, you can make redemption requests through your Financial Intermediary in accordance with the procedures applicable to your accounts. These procedures may vary according to the type of account and the Financial Intermediary involved, and customers should consult their Financial Intermediary in this regard. Financial Intermediaries are responsible for transmitting redemption orders and crediting their customers’ accounts with redemption proceeds on a timely basis. Information relating to such redemption services and charges to process a redemption of shares, if any, should be obtained by customers from their Financial Intermediaries. If you did not purchase your shares through an Employer-Sponsored Retirement Plan, you can make redemption requests through your Financial Intermediary. The price of Class K Shares is based on the next calculation of the Fund’s net asset value after your order is placed. For your redemption request to be priced at the net asset value on the day of your request, you must submit your request to your Financial Intermediary prior to that day’s close of business on the NYSE (generally 4:00 p.m. (Eastern time)). Certain Financial Intermediaries, however, may require submission of orders prior to that time. Any redemption request placed after that time will be priced at the net asset value at the close of business on the next business day. Regardless of the method the Fund uses to make payment of your redemption proceeds (check or wire), your redemption proceeds typically will be sent one to two business days after your request is submitted, but in any event, within seven days. Certain Financial Intermediaries may charge a fee to process a redemption of shares. The Fund may reject an order to sell shares under certain circumstances.
	Selling shares held directly with BlackRock	Methods of Redeeming if You Did Not Purchase Your Shares Through an Employer-Sponsored Retirement Plan Redeem by Telephone: You may sell shares held at BlackRock by telephone request. Call (800) 537-4942 for details. The Fund, its administrators and the Distributor will employ reasonable procedures to confirm that instructions communicated by telephone are genuine. The Fund and its service providers will not be liable for any loss, liability, cost or expense for acting upon telephone instructions that are reasonably believed to be genuine in accordance with such procedures. The Fund may refuse a telephone redemption request if it believes it is advisable to do so. During periods of substantial economic or market change, telephone redemptions may be difficult to complete. Please find alternative redemption methods below. Redeem by Internet: You may redeem in your account, by logging onto the BlackRock website at www.blackrock.com. Proceeds from Internet redemptions will be sent via wire to the bank account of record. Redeem in Writing: Redemption requests may be sent in proper form to BlackRock, P.O. Box 9819, Providence, Rhode Island 02940-8019 or for overnight delivery, 4400 Computer Drive, Westborough, Massachusetts 01588. Under certain circumstances, a medallion signature guarantee will be required. Payment of Redemption Proceeds Redemption proceeds may be paid by check or, if the Fund has verified banking information on file, by wire transfer. Payment by Check: BlackRock will normally mail redemption proceeds within three business days following receipt of a properly completed request, but in any event within seven days. Shares can be redeemed

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	Your Choices	Important Information for You to Know
Full or Partial Redemption of Shares (continued)	Selling shares held directly with BlackRock (continued)	by telephone and the proceeds sent by check to the shareholder at the address on record. Shareholders will pay $15 for redemption proceeds sent by check via overnight mail. You are responsible for any additional charges imposed by your bank for this service. The Fund reserves the right to reinvest any dividend or distribution amounts (e.g., income dividends or capital gains) which you have elected to receive by check should your check be returned as undeliverable or remain uncashed for more than 6 months. No interest will accrue on amounts represented by uncashed checks. Your check will be reinvested in your account at the net asset value next calculated, on the day of the investment. When reinvested, those amounts are subject to the risk of loss like any fund investment. If you elect to receive distributions in cash and a check remains undeliverable or uncashed for more than 6 months, your cash election may also be changed automatically to reinvest and your future dividend and capital gains distributions will be reinvested in the Fund at the net asset value as of the date of payment of the distribution. Payment by Wire Transfer: Payment for redeemed shares for which a redemption order is received before 4:00 p.m. (Eastern time) on a business day is normally made in Federal funds wired to the redeeming shareholder on the next business day, provided that the Fund’s custodian is also open for business. Payment for redemption orders received after 4:00 p.m. (Eastern time) or on a day when the Fund’s custodian is closed is normally wired in Federal funds on the next business day following redemption on which the Fund’s custodian is open for business. The Fund reserves the right to wire redemption proceeds within seven days after receiving a redemption order if, in the judgment of the Fund, an earlier payment could adversely affect the Fund. Shares can be redeemed by Federal wire transfer to a single previously designated bank account. No charge for wiring redemption payments with respect to Class K Shares is imposed by the Fund. You are responsible for any additional charges imposed by your bank for wire transfers. The Fund is not responsible for the efficiency of the Federal wire system or the shareholder’s firm or bank. To change the name of the single, designated bank account to receive wire redemption proceeds, it is necessary to send a written request to the Fund at the address on the back cover of this prospectus. *** If you make a redemption request before the Fund has collected payment for the purchase of shares, the Fund may delay mailing your proceeds. This delay will usually not exceed ten days.
Redemption Proceeds		Under normal circumstances, the Fund expects to meet redemption requests by using cash or cash equivalents in its portfolio or by selling portfolio assets to generate cash. During periods of stressed market conditions, when a significant portion of the Fund’s portfolio may be comprised of less-liquid investments, the Fund may be more likely to limit cash redemptions and may determine to pay redemption proceeds by (i) borrowing under a line of credit it has entered into with a group of lenders, (ii) borrowing from another BlackRock Fund pursuant to an interfund lending program, to the extent permitted by the Fund’s investment policies and restrictions as set forth in the SAI, and/or (iii) transferring portfolio securities in-kind to you. The SAI includes more information about the Fund’s line of credit and interfund lending program, to the extent applicable. If the Fund pays redemption proceeds by transferring portfolio securities in-kind to you, you may pay transaction costs to dispose of the securities, and you may receive less for them than the price at which they were valued for purposes of redemption.

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How to Exchange Shares or Transfer Your Account

	Your Choices	Important Information for You to Know
Exchange Privilege	Selling shares of one BlackRock Fund to purchase shares of another BlackRock Fund (“exchanging”)	Class K Shares of the Fund are generally exchangeable for shares of the same class of another BlackRock Fund. Investors who currently own Class K Shares of the Fund may make exchanges into Class K Shares of other BlackRock Funds except for investors holding shares through certain client accounts at Financial Intermediaries that are omnibus with the Fund and do not meet applicable minimums. There is no required minimum amount with respect to exchanges of Class K Shares. You may only exchange into Class K Shares of a BlackRock Fund that is open to new investors or in which you have a current account, if the BlackRock Fund is closed to new investors. To exercise the exchange privilege, you may contact your Financial Intermediary. Alternatively, if your account is held directly with BlackRock, you may: (i) call (800) 537-4942 and speak with one of our representatives, (ii) make the exchange via the Internet by accessing your account online at www.blackrock.com, or (iii) send a written request to the Fund at the address on the back cover of this prospectus. Please note, if you indicated on your New Account Application that you did not want the Telephone Exchange Privilege, you will not be able to place exchanges via the telephone until you update this option either in writing or by calling (800) 537-4942. The Fund has the right to reject any telephone request for any reason. Although there is currently no limit on the number of exchanges that you can make, the exchange privilege may be modified or terminated at any time in the future. The Fund may suspend or terminate your exchange privilege at any time for any reason, including if the Fund believes, in its sole discretion, that you are engaging in market timing activities. See “Short-Term Trading Policy” below. For U.S. federal income tax purposes a share exchange is a taxable event and a capital gain or loss may be realized. Please consult your tax adviser or other Financial Intermediary before making an exchange request.
Transfer Shares to Another Financial Intermediary	Transfer to a participating Financial Intermediary	You may transfer your Class K Shares of the Fund only to another Financial Intermediary that has entered into an agreement with the Distributor. Certain shareholder services may not be available for the transferred shares. All future trading of these assets must be coordinated by the receiving firm. Please contact your Financial Intermediary to accomplish the transfer of your Class K Shares.
	Transfer to a non-participating Financial Intermediary	You must either: • Transfer your Class K Shares to an account with the Fund; or • Sell your Class K Shares. Please contact your Financial Intermediary to accomplish the transfer of your Class K Shares.

Additional Purchase and Redemption Information Applicable to the Fund if You Are Not Purchasing Shares Through an Employer-Sponsored Retirement Plan

If you are not purchasing shares through an Employer-Sponsored Retirement Plan, the Fund may authorize one or more banks, savings and loan associations and other financial institutions (each a “Service Organization”) to accept purchase and redemption orders on its behalf. Such Service Organizations may be authorized to designate other intermediaries to accept purchase and redemption orders on the Fund’s behalf. If you purchase or redeem shares through a Service Organization or its designee, that entity may have its own deadlines for the receipt of the purchase or redemption order that may be earlier than those stated in the prospectus. The Fund will be deemed to have received a purchase or redemption order when a Service Organization or, if applicable, that Service Organization’s authorized designee, accepts the order. These orders will be priced at the Fund’s net asset value per share next calculated after they are so accepted.

Funds’ Rights

Each Fund may:

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■	Suspend the right of redemption if trading is halted or restricted on the NYSE or under other emergency conditions described in the Investment Company Act;
■	Postpone the date of payment upon redemption if trading is halted or restricted on the NYSE or under other emergency conditions described in the Investment Company Act or if a redemption request is made before the Fund has collected payment for the purchase of shares;
■	Redeem shares for property other than cash as may be permitted under the Investment Company Act; and
■	Redeem shares involuntarily in certain cases, such as when the value of a shareholder account falls below a specified level.

Short-Term Trading Policy

The Board of Directors of the Corporation (the “Board”) has determined that the interests of long-term shareholders and each Fund’s ability to manage its investments may be adversely affected when shares are repeatedly bought, sold or exchanged in response to short-term market fluctuations — also known as “market timing.” The Funds are not designed for market timing organizations or other entities using programmed or frequent purchases and sales or exchanges. The exchange privilege is not intended as a vehicle for short-term trading. Excessive purchase and sale or exchange activity may interfere with portfolio management, increase expenses and taxes and may have an adverse effect on the performance of a Fund and its returns to shareholders. For example, large flows of cash into and out of a Fund may require the management team to allocate a significant amount of assets to cash or other short-term investments or sell securities, rather than maintaining such assets in securities selected to achieve the Fund’s investment objective. Frequent trading may cause a Fund to sell securities at less favorable prices, and transaction costs, such as brokerage commissions, can reduce a Fund’s performance.

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exchanges of shares are netted against one another and the identity of individual purchasers, redeemers and exchangers whose orders are aggregated may not be known by a Fund. While the Funds monitor for market timing activity, the Funds may be unable to identify such activities because the netting effect in omnibus accounts often makes it more difficult to locate and eliminate market timers from the Funds. The Distributor has entered into agreements with respect to Financial Intermediaries that maintain omnibus accounts with the Funds pursuant to which such Financial Intermediaries undertake to cooperate with the Distributor in monitoring purchase, exchange and redemption orders by their customers in order to detect and prevent short-term or excessive trading in the Fund’s shares through such accounts. Identification of market timers may also be limited by operational systems and technical limitations. In the event that a Financial Intermediary is determined by a Fund to be engaged in market timing or other improper trading activity, the Distributor may terminate such Financial Intermediary’s agreement with the Distributor, suspend such Financial Intermediary’s trading privileges or take other appropriate actions.

There is no assurance that the methods described above will prevent market timing or other trading that may be deemed abusive.

The Funds may from time to time use other methods that they believe are appropriate to deter market timing or other trading activity that may be detrimental to the Fund or long-term shareholders.

Master/Feeder Structure

However, each feeder fund can set its own transaction minimums, fund-specific expenses, and other conditions. This means that one feeder fund could offer access to the Series on more attractive terms, or could experience better performance, than another feeder fund. In addition, large purchases or redemptions by one feeder fund could negatively affect the performance of other feeder funds that invest in the Series. Information about other feeder funds, if any, is available by calling (800) 537-4942.

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Management of the Funds

BlackRock

BlackRock is the investment manager for the Series in which Russell 2000 Small-Cap Index Fund invests and for MSCI EAFE International Index Fund. BlackRock manages the investments and business operations of the Series and MSCI EAFE International Index Fund subject to the oversight of the Master LLC’s and Corporation’s Board of Directors, as applicable. While BlackRock is ultimately responsible for the management of the Series and MSCI EAFE International Index Fund, it is able to draw upon the trading, research and expertise of its asset management affiliates for portfolio decisions and management with respect to certain portfolio securities. BlackRock is an indirect, wholly-owned subsidiary of BlackRock, Inc.

The contractual fee rate payable to the Administrator as a percentage of Russell 2000 Small-Cap Index Fund’s average daily net assets under the Administration Agreement is 0.04%.

For the fiscal year ended December 31, 2017, the administration fee rate, net of any applicable waivers, for Russell 2000 Small-Cap Index Fund was 0.00%.

BlackRock has contractually agreed to cap net expenses (excluding (i) interest, taxes, dividends tied to short sales, brokerage commissions, and other expenditures which are capitalized in accordance with generally accepted accounting principles; (ii) expenses incurred directly or indirectly by a Fund as a result of investments in other investment companies and pooled investment vehicles; (iii) other expenses attributable to, and incurred as a result of, a Fund’s investments; and (iv) extraordinary expenses (including litigation expenses) not incurred in the ordinary course of a Fund’s business, if any) of Class K Shares of the Funds at the levels shown below (and in a Fund’s fees and expense table in the “Fund Overview” section of the prospectus). Items (i), (ii), (iii) and (iv) in the preceding sentence are referred to in this prospectus as “Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses.” To achieve these expense caps, BlackRock has agreed to waive and/or reimburse fees or expenses if these operating expenses exceed a certain limit.

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	Contractual Cap ¹ on Total Annual Fund Operating Expenses ² (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses)
Master Small Cap Index Series	0.07%

¹	The contractual cap is in effect through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series.

²	As a percentage of average daily net assets.

	Contractual Caps ¹ on Total Annual Fund Operating Expenses ² (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses)
Fund
Russell 2000 Small-Cap Index Fund	0.07%
MSCI EAFE International Index Fund	0.07%

¹	The contractual caps are in effect through April 30, 2019. The contractual agreement may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the applicable Fund.

²	As a percentage of average daily net assets.

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Defendants violated Section 36(b) of the Investment Company Act by receiving allegedly excessive investment advisory fees from Global Allocation and Equity Dividend. The Consolidated Complaint seeks, among other things, to recover on behalf of Global Allocation and Equity Dividend all allegedly excessive advisory fees received by the Defendants in the period beginning one year prior to the filing of the lawsuit and ending on the date of judgment, along with purported lost investment returns on those amounts, plus interest. The Defendants believe the claims in the Consolidated Complaint are without merit and intend to vigorously defend the action.

Portfolio Manager Information

Master Small Cap Index Series and MSCI EAFE International Index Fund are managed by a team of financial professionals. Information about the portfolio managers is provided below.

Portfolio Manager	Primary Role	Since	Title and Recent Biography
Alan Mason	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2014	Managing Director of BlackRock, Inc. since 2009; Managing Director of Barclays Global Investors (“BGI”) from 2008 to 2009; Principal of BGI from 1996 to 2008.
Greg Savage, CFA	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2012	Managing Director of BlackRock, Inc. since 2010; Director of BlackRock, Inc. in 2009; Principal of BGI from 2007 to 2009; Associate of BGI from 1999 to 2007.
Jennifer Hsui, CFA	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2016	Managing Director of BlackRock, Inc. since 2011; Director of BlackRock, Inc. from 2009 to 2011; Principal of BGI from 2006 to 2009.
Creighton Jue, CFA	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2016	Managing Director of BlackRock, Inc. since 2011; Director of BlackRock, Inc. from 2009 to 2011; Principal of BGI from 2000 to 2009.
Rachel Aguirre	Jointly and primarily responsible for the day-to-day management of the Series’ and the Fund’s portfolio, including setting the Series’ and the Fund’s overall investment strategy and overseeing the management of the Series and the Fund.	2016	Managing Director of BlackRock, Inc. since 2018; Director of BlackRock, Inc. from 2012 to 2017; Vice President of BlackRock, Inc. from 2009 to 2011; Principal and Portfolio Manager of BGI from 2005 to 2009.

Conflicts of Interest

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Valuation of Fund Investments

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(Eastern time). The net asset value used in determining your share price is the next one calculated after your purchase or redemption order is received.

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Dividends, Distributions and Taxes

BUYING A DIVIDEND

Your tax consequences from an investment in a Fund will depend on whether you have invested through a qualified tax-exempt plan described in section 401(a) of the Internal Revenue Code (a “Qualified Plan”).

Investments through a Qualified Plan

Special tax rules apply to investments made through Qualified Plans. If you are invested through a Qualified Plan (and Fund shares are not “debt-financed property” to the plan), then you will not be subject to U.S. federal income tax on the dividends paid by a Fund or the gain realized from a redemption or exchange of Fund shares until you withdraw or receive distributions from the plan. Distributions you receive from the Qualified Plan may be subject to U.S. federal withholding tax depending on the kind of payment you receive.

Investments Not Made through Qualified Plans

If you are not invested through a Qualified Plan, you will generally pay tax on dividends from a Fund whether you receive them in cash or additional shares. If you redeem Fund shares or exchange them for shares of another fund, you generally will be treated as having sold your shares and any gain on the transaction may be subject to tax. Fund distributions derived from qualified dividend income, which consists of dividends received from U.S. corporations and qualifying foreign corporations, and long-term capital gains, are eligible for taxation at a maximum rate of 15% or 20% for individuals, depending on whether their income exceeds certain threshold amounts, which are adjusted annually for inflation.

Special Considerations for Non-U.S. Persons

If you are not invested through a Qualified Plan and you are neither a tax resident nor a citizen of the United States or if you are a foreign entity (other than a pass-through entity to the extent owned by U.S. persons), a Fund’s ordinary income dividends will generally be subject to a 30% U.S. withholding tax, unless a lower treaty rate applies. However, certain distributions paid to a foreign shareholder and reported by a Fund as capital gain dividends, interest-related dividends or short-term capital gain dividends may be eligible for an exemption from U.S. withholding tax.

Separately, a 30% withholding tax is currently imposed on U.S.-source dividends, interest and other income items and will be imposed on proceeds from the sale, redemption or disposition of property producing U.S.-source dividends and interest paid after December 31, 2018, to (i) certain foreign financial institutions and investment funds and (ii) certain other foreign entities. To avoid withholding, foreign financial institutions and investment funds will generally either need to (a) collect and report to the IRS detailed information identifying their U.S. accounts and U.S. account holders, comply with due diligence procedures for identifying U.S. accounts and withhold tax on certain payments made to noncomplying foreign entities and account holders or (b) if an intergovernmental agreement is entered into and implementing legislation is adopted, comply with the agreement and legislation. Other foreign entities will generally either need to provide detailed information identifying each substantial U.S. owner or certify there are no such owners.

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Financial Highlights

The financial highlights tables are intended to help investors understand the financial performance of the Class K Shares of each Fund for the periods since the commencement of operations of the Class K Shares. Certain information reflects the financial results for a single share of the Fund. The total returns in the tables represent the rate of return that an investor would have earned (or lost) on an investment in the shares of the Fund, assuming reinvestment of all dividends and/or distributions. The information has been audited by Deloitte & Touche LLP, whose report, along with each Fund’s financial statements, are included in the respective Fund’s annual report. You may obtain copies of the annual report, at no cost, by calling (800) 537-4942 (toll free) from 8:00 a.m. to 6:00 p.m. (Eastern time) on any business day.

For MSCI EAFE International Index Fund, the financial highlights for the periods prior to August 1, 2016 reflect the “master/feeder” structure in place during the periods shown and “Master International Index” in such financial highlights refers to Master International Index Series, a series of the Master LLC.

Russell 2000 Small-Cap Index Fund

	Class K
	Year Ended December 31,
(For a share outstanding throughout each period)	2017	2016	2015	2014	2013
Net asset value, beginning of year	$ 17.79	$ 15.35	$16.62	$17.53	$13.01
Net investment income ^(a)	0.27	0.24	0.25	0.23	0.25
Net realized and unrealized gain (loss)	2.34	3.02	(0.97)	0.54	4.81
Net increase (decrease) from investment operations	2.61	3.26	(0.72)	0.77	5.06
Distributions: ^(b)
From net investment income	(0.21)	(0.22)	(0.14)	(0.27)	(0.20)
From net realized gain	(0.42)	(0.60)	(0.41)	(1.41)	(0.34)
Total distributions	(0.63)	(0.82)	(0.55)	(1.68)	(0.54)
Net asset value, end of year	$ 19.77	$ 17.79	$15.35	$16.62	$17.53
Total Return ^(c)
Based on net asset value	14.69%	21.32%	(4.41)%	4.87%	39.14%
Ratios to Average Net Assets ^(d)(e)
Total expenses	0.14%	0.17% ^(f)	0.21%	0.32%	0.49%
Total expenses after fees waived and/or reimbursed	0.07%	0.10% ^(f)	0.13%	0.18%	0.25%
Net investment income	1.40%	1.48% ^(f)	1.50%	1.35%	1.57%
Supplemental Data
Net assets, end of year (000)	$474,830	$60,086	$8,338	$2,617	$1,196
Portfolio turnover rate of the Series	30%	39%	37%	21%	22%

^(a)	Based on average shares outstanding.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Where applicable, assumes the reinvestment of distributions.
^(d)	Includes the Fund’s share of the Series’ allocated expenses and/or net investment income.
^(e)	Includes the Fund’s share of the Series’ allocated fees waived of less than 0.01%.
^(f)	Excludes expenses incurred indirectly of 0.01% as a result of the Series’ investments in underlying funds.

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Financial Highlights (concluded)

MSCI EAFE International Index Fund

	Class K
	Year Ended December 31,
(For a share outstanding throughout each period)	2017	2016	2015	2014	2013
Net asset value, beginning of year	$ 11.61	$ 11.82	$ 12.21	$ 13.11	$11.06
Net investment income ^(a)	0.38	0.38	0.28	0.34	0.28
Net realized and unrealized gain (loss)	2.54	(0.26)	(0.38)	(1.14)	2.09
Net increase (decrease) from investment operations	2.92	0.12	(0.10)	(0.80)	2.37
Distributions: ^(b)
From net investment income	(0.35)	(0.33)	(0.29)	(0.10)	(0.32)
Total distributions	(0.35)	(0.33)	(0.29)	(0.10)	(0.32)
Net asset value, end of year	$ 14.18	$ 11.61	$ 11.82	$ 12.21	$13.11
Total Return ^(c)
Based on net asset value	25.17%	1.03%	(0.81)%	(6.12)%	21.57%
Ratios to Average Net Assets
Total expenses	0.06%	0.07% ^(d)(e)	0.12% ^(d)(e)	0.15% ^(d)(e)	0.36% ^(d)(e)
Total expenses after fees waived and/or reimbursed and/or paid indirectly	0.06%	0.07% ^(d)(e)	0.07% ^(d)(e)	0.11% ^(d)(e)	0.30% ^(d)(e)
Net investment income	2.80%	3.25% ^(d)(e)	2.25% ^(d)(e)	2.65% ^(d)(e)	2.29% ^(d)(e)
Supplemental Data
Net assets, end of year (000)	$9,509,257	$4,042,470	$113,314	$16,014	$2,336
Portfolio turnover rate	23%	42% ^(f)	9% ^(g)	6% ^(g)	8% ^(g)

^(a)	Based on average shares outstanding.
^(b)	Distributions for annual periods determined in accordance with U.S. federal income tax regulations.
^(c)	Where applicable, assumes the reinvestment of distributions.
^(d)	Includes the Fund’s share of Master International Index’s allocated expenses and/or net investment income.
^(e)	Includes the Fund’s share of Master International Index’s allocated fees waived of less than 0.01%.
^(f)	Portfolio turnover rate includes transactions from Master International Index prior to August 1, 2016.
^(g)	Portfolio turnover rate of Master International Index.

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