# EDGAR Filing Document

**Accession Number:** 0000035315
**File Stem:** 0000035315-25-001144
**Filing Date:** 2025-11
**Character Count:** 6730
**Document Hash:** 9edca79a5fdc80feb88d3b18de8fade8
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000035315-25-001144.hdr.sgml**: 20251121

**ACCESSION NUMBER**: 0000035315-25-001144

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 26

**FILED AS OF DATE**: 20251121

**DATE AS OF CHANGE**: 20251121

**EFFECTIVENESS DATE**: 20251121

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** FIDELITY SALEM STREET TRUST
- **CENTRAL INDEX KEY:** 0000035315

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0430

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 002-41839
- **FILM NUMBER:** 251505573

**BUSINESS ADDRESS:**
- **STREET 1:** 245 SUMMER STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210
- **BUSINESS PHONE:** 617-563-7000

**MAIL ADDRESS:**
- **STREET 1:** 245 SUMMER STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** FIDELITY FIXED INCOME TRUST
- **DATE OF NAME CHANGE:** 19920703

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** FIDELITY FLEXIBLE BOND FUND
- **DATE OF NAME CHANGE:** 19860904

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** FIDELITY CORPORATE BOND FUND INC
- **DATE OF NAME CHANGE:** 19851225

## Series and Classes Contracts Data

### Fidelity SAI Small-Mid Cap 500 Index Fund (Series ID: S000050321)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                | Ticker Symbol | Class ID   |
| Fidelity SAI Small-Mid Cap 500 Index Fund | FZFLX         | C000158877 |

---

## Series and Classes Contracts Data

### Fidelity SAI Small-Mid Cap 500 Index Fund (Series ID: S000050321)

| Class ID   | Class Name                                | Ticker Symbol   |
|:---|:---|:---|
| C000158877 | Fidelity SAI Small-Mid Cap 500 Index Fund | FZFLX           |

?xml version='1.0' encoding='ASCII'? Prospectus - Investment Objective

**Supplement to the Fidelity® SAI Small-Mid Cap 500 Index Fund September 29, 2025 Prospectus** 

*At its November 2025 meeting, the Board of Trustees ("Board") approved changes to the name and investment policy for the fund. Effective December 22, 2025, the fund will (i) change its name to Fidelity® SAI Small-Mid Cap Momentum Index Fund, (ii) change its 80% policy to normally invest at least 80% of assets in securities included in the Fidelity U.S. Small-Mid Cap Momentum Focus Index℠, and (iii) change its benchmark index to the Fidelity U.S. Small-Mid Cap Momentum Focus Index℠.*

Effective December 22, 2025, the following information replaces similar information found in the "Fund Summary" section under the "Principal Investment Strategies" heading.

* Normally investing at least 80% of assets in securities included in the Fidelity U.S. Small-Mid Cap Momentum Focus Index℠.

The Fidelity U.S. Small-Mid Cap Momentum Focus Index℠ is designed to reflect a well-diversified portfolio that invests in companies based on price and earnings momentum metrics. It is a subset of the Fidelity U.S. Extended Investable Market Index℠, a float-adjusted market capitalization-weighted index designed to reflect the performance of U.S. mid- and small-cap stocks. The Fidelity U.S. Extended Investable Market Index℠ is a subset of the Fidelity U.S. Total Investable Market Index℠, excluding the 500 largest companies.

Effective December 22, 2025, the following information supplements information found in the "Fund Summary" section under the "Principal Investment Risks" heading.

* *Rules-Based Strategy Risk.*

Although the index uses a rules-based proprietary index methodology, there is no guarantee that this methodology will be successful.

* *Momentum Securities Risk.*

Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks that exhibit positive momentum signals, there is no guarantee that this methodology will be successful. Stocks that previously exhibited high momentum characteristics may not experience positive momentum or may experience more volatility than the market as a whole.

Effective December 22, 2025, the following information replaces similar information found in the "Investment Details" section under the "Principal Investment Strategies" heading.

Geode Capital Management, LLC (Geode) normally invests at least 80% of the fund's assets in securities included in the Fidelity U.S. Small-Mid Cap Momentum Focus Index℠.

The Fidelity U.S. Small-Mid Cap Momentum Focus Index℠ is designed to reflect a well-diversified portfolio that invests in companies based on price and earnings momentum metrics. It is a subset of the Fidelity U.S. Extended Investable Market Index℠, a float-adjusted market capitalization-weighted index designed to reflect the performance of U.S. mid- and small-cap stocks. The Fidelity U.S. Extended Investable Market Index℠ is a subset of the Fidelity U.S. Total Investable Market Index℠, excluding the 500 largest companies.

Effective December 22, 2025, the following information supplements information found in the "Investment Details" section under the "Principal Investment Strategies" heading.

*Rules-Based Strategy Risk.* Although the index uses a rules-based proprietary index methodology, there is no guarantee that this methodology will be successful.

*Momentum Securities Risk.* Although the fund's underlying index uses a rules-based proprietary index methodology that is designed to identify stocks that exhibit positive momentum signals, there is no guarantee that this methodology will be successful. Stocks that previously exhibited high momentum characteristics may not experience positive momentum or may experience more volatility than the market as a whole. In addition, there may be periods when momentum investing is out of favor and therefore, during such periods, the investment performance of the fund may suffer.

Effective December 22, 2025, the following information replaces similar information found in the "Investment Details" section under the "Shareholder Notice" heading.

Fidelity® SAI Small-Mid Cap Momentum Index Fund normally invests at least 80% of its assets in securities included in the Fidelity U.S. Small-Mid Cap Momentum Focus Index℠.

*At its November 2025 meeting, the Board also approved, subject to shareholder approval, a proposal to modify the fund's fundamental investment objective and convert the fundamental investment objective to non-fundamental. If approved by shareholders, the fundamental investment objective will be modified to align with the new fund name and will take effect on December 22, 2025. The changes to the fund's name and investment policy discussed above are not subject to shareholder approval.*

SV3-PSTK-1125-105 1.9878820.105 November 21, 2025