BLACKROCK INDEX FUNDS, INC.
iShares Russell 2000 Small-Cap Index Fund
iShares MSCI EAFE International Index Fund
(each, a “Fund”)
Supplement dated May 16, 2025 to the Summary Prospectuses and the
Prospectuses of each Fund, dated April 30, 2025, as amended or supplemented to date
Effective June 30, 2025, the following changes are made to each Fund’s Summary Prospectuses and Prospectuses, as applicable:
The section of the Summary Prospectuses entitled “Key Facts About iShares Russell 2000 Small-Cap Index Fund — Portfolio Managers” and the section of the Prospectuses entitled “Fund Overview — Key Facts About iShares Russell 2000 Small-Cap Index Fund — Portfolio Managers” are deleted in their entirety and replaced with the following:
| Portfolio Manager | Portfolio Manager of the Series Since |
Title | ||
| Jennifer Hsui, CFA | 2016 | Managing Director of BlackRock, Inc. | ||
| Matt Waldron, CFA | 2025 | Managing Director of BlackRock, Inc. | ||
| Peter Sietsema, CFA | 2025 | Director of BlackRock, Inc. | ||
| Steven White | 2025 | Director of BlackRock, Inc. |
The section of the Summary Prospectuses entitled “Key Facts About iShares MSCI EAFE International Index Fund — Portfolio Managers” and the section of the Prospectuses entitled “Fund Overview — Key Facts About iShares MSCI EAFE International Index Fund — Portfolio Managers” are deleted in their entirety and replaced with the following:
| Portfolio Manager | Portfolio Manager of the Fund Since |
Title | ||
| Jennifer Hsui, CFA | 2016 | Managing Director of BlackRock, Inc. | ||
| Matt Waldron, CFA | 2025 | Managing Director of BlackRock, Inc. | ||
| Peter Sietsema, CFA | 2025 | Director of BlackRock, Inc. | ||
| Steven White | 2025 | Director of BlackRock, Inc. |
The section of the Prospectuses entitled “Details About the Fund — How Each Fund Invests — Russell 2000 Small-Cap Index Fund — About the Portfolio Management Team of Master Small Cap Index Series” is deleted in its entirety and replaced with the following:
| ABOUT THE PORTFOLIO MANAGEMENT TEAM OF MASTER SMALL CAP INDEX SERIES |
| The Series is managed by a team of financial professionals. Jennifer Hsui, CFA, Matt Waldron, CFA, Peter Sietsema, CFA, and Steven White 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. |
The section of the Prospectuses entitled “Details About the Fund — How Each Fund Invests — MSCI EAFE International Index Fund — About the Portfolio Management Team of MSCI EAFE International Index Fund” is deleted in its entirety and replaced with the following:
| ABOUT THE PORTFOLIO MANAGEMENT TEAM OF MSCI EAFE INTERNATIONAL INDEX FUND |
| The Fund is managed by a team of financial professionals. Jennifer Hsui, CFA, Matt Waldron, CFA, Peter Sietsema, CFA, and Steven White 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. |
The sections of the Prospectuses for the Investor and Institutional Shares, the Class K Shares, and the Investor P Shares entitled “Management of the Funds — Portfolio Manager Information” is deleted in its entirety and replaced with the following:
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.
| Portfolio Manager | Primary Role | Since | Title and Recent Biography | |||
| Jennifer Hsui, CFA | Jointly and primarily responsible for the day-to-day management of each Master Portfolio, including setting the Master Portfolio’s overall investment strategy and overseeing the management of the Master Portfolio. | 2016 | Managing Director of BlackRock, Inc. since 2011; Director of BlackRock, Inc. from 2009 to 2011; Principal of BGI from 2006 to 2009. | |||
| Matt Waldron, CFA | Jointly and primarily responsible for the day-to-day management of the Fund, including setting the Fund’s overall investment strategy and overseeing the management of the Fund. | 2025 | Managing Director of BlackRock, Inc. since 2024; Director of BlackRock, Inc from 2010 to 2024. | |||
| Peter Sietsema, CFA | Jointly and primarily responsible for the day-to-day management of the Fund, including setting the Fund’s overall investment strategy and overseeing the management of the Fund. | 2025 | Director of BlackRock, Inc. since 2013. | |||
| Steven White | Jointly and primarily responsible for the day-to-day management of the Fund, including setting the Fund’s overall investment strategy and overseeing the management of the Fund. | 2025 | Director of BlackRock, Inc. since 2020. |
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The section of the Prospectuses for the Class G Shares entitled “Management of the Fund — Portfolio Manager Information” is deleted in its entirety and replaced with the following:
Information regarding the portfolio managers of 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.
| Portfolio Manager | Primary Role | Since | Title and Recent Biography | |||
| Jennifer Hsui, CFA | Jointly and primarily responsible for the day-to-day management of each Master Portfolio, including setting the Master Portfolio’s overall investment strategy and overseeing the management of the Master Portfolio. | 2016 | Managing Director of BlackRock, Inc. since 2011; Director of BlackRock, Inc. from 2009 to 2011; Principal of BGI from 2006 to 2009. | |||
| Matt Waldron, CFA | Jointly and primarily responsible for the day-to-day management of the Fund, including setting the Fund’s overall investment strategy and overseeing the management of the Fund. | 2025 | Managing Director of BlackRock, Inc. since 2024; Director of BlackRock, Inc from 2010 to 2024. | |||
| Peter Sietsema, CFA | Jointly and primarily responsible for the day-to-day management of the Fund, including setting the Fund’s overall investment strategy and overseeing the management of the Fund. | 2025 | Director of BlackRock, Inc. since 2013. | |||
| Steven White | Jointly and primarily responsible for the day-to-day management of the Fund, including setting the Fund’s overall investment strategy and overseeing the management of the Fund. | 2025 | Director of BlackRock, Inc. since 2020. |
Shareholders should retain this Supplement for future reference.
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