# EDGAR Filing Document

**Accession Number:** 0001026144
**File Stem:** 0001410368-26-017008
**Filing Date:** 2026-2
**Character Count:** 4482
**Document Hash:** 16af67b29d87aaaae8fa9831213d2679
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001410368-26-017008.hdr.sgml**: 20260224

**ACCESSION NUMBER**: 0001410368-26-017008

**CONFORMED SUBMISSION TYPE**: NPORT-P

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260224

**DATE AS OF CHANGE**: 20260224

**PERIOD START**: 20251231

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** BLACKROCK INDEX FUNDS, INC.
- **CENTRAL INDEX KEY:** 0001026144

**ORGANIZATION NAME:**
- **EIN:** 223483675
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** NPORT-P
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-07899
- **FILM NUMBER:** 26668896

**BUSINESS ADDRESS:**
- **STREET 1:** 100 BELLEVUE PARKWAY
- **CITY:** WILMINGTON
- **STATE:** DE
- **ZIP:** 19809
- **BUSINESS PHONE:** 800-441-7762

**MAIL ADDRESS:**
- **STREET 1:** 100 BELLEVUE PARKWAY
- **CITY:** WILMINGTON
- **STATE:** DE
- **ZIP:** 19809

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MERRILL LYNCH INDEX FUNDS INC
- **DATE OF NAME CHANGE:** 19961031

## Series and Classes Contracts Data

### iShares Russell 2000 Small-Cap Index Fund (Series ID: S000003118)

| Class ID   | Class Name        | Ticker Symbol   |
|:---|:---|:---|
| C000008451 | Investor A        |  |
| C000008452 | Institutional     |  |
| C000099169 | Class K           |  |
| C000201957 | Investor P Shares |  |

## Form NPORT-P: Monthly Portfolio Investments Report

### NPORT-P: Part A: General Information

**Item A.1. Information about the Registrant.**

- **a. Name of Registrant:** BlackRock Index Funds, Inc.

- **b. Investment Company Act file number:** 811-07899

- **c. CIK number of Registrant:** 0001026144

- **d. LEI of Registrant:** 549300R0LV8YE1DSQ620

- **e. Address and telephone number of Registrant.**

  - **Street Address 1:** 100 Bellevue Parkway

  - **City:** Wilmington

  - **State:** DE

  - **Foreign country:** US

  - **Zip / Postal Code:** 19809

  - **Telephone number:** 800-441-7762

**Item A.2. Information about the Series.**

- **a. Name of Series:** iShares Russell 2000 Small-Cap Index Fund

- **b. EDGAR series identifier (if any):** S000003118

- **c. LEI of Series:** 549300URA4LL162MRE56

**Item A.3. Reporting period.**

- **a. Date of fiscal year-end:** 2025-12-31

- **b. Date as of which information is reported:** 2025-12-31

**Item A.4. Final filing**

Does the Fund anticipate that this will be its final filing on Form N-PORT? **No**

### Fund Information

**Total Assets:** $3184211342.77

**Total Liabilities:** $719612.28

**Net Assets:** $3183491730.49

**Monthly Return Information**

| Class               | Month 1 Return (%)   | Month 2 Return (%)   | Month 3 Return (%)   |
|:---|:---|:---|:---|
| Class ID C000008451 | 1.79%                | 0.95%                | -0.62%               |
| Class ID C000008452 | 1.82%                | 0.95%                | -0.57%               |
| Class ID C000099169 | 1.81%                | 0.98%                | -0.59%               |
| Class ID C000201957 | 1.75%                | 0.95%                | -0.62%               |

**Monthly Gains & Losses**

| Period   | Net Realized Gain/Loss   | Net Unrealized Appreciation/Depreciation   |
|:---|:---|:---|
| Month 1  | $0.00                    | $0.00                                      |
| Month 2  | $0.00                    | $0.00                                      |
| Month 3  | $0.00                    | $0.00                                      |

### Schedule of Portfolio Investments

| Name                        | Title                         | Identifiers                                   | Payoff Profile   | Asset Category   | Issuer Category   | Country   |   Balance | Units   | Value (USD)    | % of Net Assets   | Maturity Date   | Coupon Type   | Annualized Rate (%)   | Restricted?   | Fair Value Level   | Lending Status   |
|:---|:---|:---|:---|:---|:---|:---|---:|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| BlackRock Index Funds, Inc. | Master Small Cap Index Series | CUSIP: 000000000<br>LEI: 549300R0LV8YE1DSQ620 | Long             | EC               | RF                | US        | 108172098 | NS      | $3183668391.93 | 100.01%           |  |  |  | No            | N/A                | On Loan: No      |

### Signature

**Date Signed:** 2026-01-28

**Name of Applicant:** BlackRock Index Funds, Inc.

**Signature:** Chuck Pulsfort

**Name of Signer:** Chuck Pulsfort

**Title:** Assistant Treasurer