# EDGAR Filing Document

**Accession Number:** 0000880195
**File Stem:** 0000880195-25-000356
**Filing Date:** 2025-6
**Character Count:** 2986
**Document Hash:** c2d727d5947f642031d73493b0ff8936
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000880195-25-000356.hdr.sgml**: 20250606

**ACCESSION NUMBER**: 0000880195-25-000356

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250606

**DATE AS OF CHANGE**: 20250606

**EFFECTIVENESS DATE**: 20250606

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** FIDELITY ABERDEEN STREET TRUST
- **CENTRAL INDEX KEY:** 0000880195

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 0331

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-43529
- **FILM NUMBER:** 251029344

**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 INSTITUTIONAL INVESTORS TRUST
- **DATE OF NAME CHANGE:** 19920811

## Series and Classes Contracts Data

### Fidelity Multi-Asset Index Fund (Series ID: S000040658)

---

|  |  |  |
|:---|:---|:---|
| Class Name                      | Ticker Symbol | Class ID   |
| Fidelity Multi-Asset Index Fund | FFNOX         | C000126039 |

---

## Series and Classes Contracts Data

### Fidelity Multi-Asset Index Fund (Series ID: S000040658)

| Class ID   | Class Name                      | Ticker Symbol   |
|:---|:---|:---|
| C000126039 | Fidelity Multi-Asset Index Fund | FFNOX           |

**Supplement to the Fidelity® Multi-Asset Index Fund April 29, 2025 Prospectus**

Effective October 1, 2025, the following information replaces similar information found in the "Investment Details" section under the "Description of Underlying Fidelity® Funds" heading.

*Fidelity*® *International Bond Index Fund* 

The fund seeks to provide a high level of current income. Normally investing at least 80% of assets in securities included in the Bloomberg Global Aggregate ex USD ex EM Float Adjusted RIC Diversified Index (Hedged USD), which is a multi-currency benchmark that includes fixed-rate treasury, government-related, corporate and securitized bonds from developed markets issuers while excluding USD denominated debt.

Effective October 1, 2025, the following information replaces similar information found in the "Appendix" section under the "Additional Index Information" heading.

**Fidelity Multi-Asset Composite Index℠** is a customized blend of unmanaged indexes, weighted as follows: S&P 500® Index - 41%; Dow Jones U.S. Completion Total Stock Market Index℠ - 10%; MSCI EAFE Index (Net MA) - 24%; MSCI Emerging Markets Index (Net MA) - 10%; Bloomberg U.S. Aggregate Bond Index - 7%; Bloomberg U.S. Long Treasury Bond Index - 5%; and Bloomberg Global Aggregate ex USD ex EM Float Adjusted RIC Diversified Index (Hedged USD) - 3%. The composition differed in periods prior to October 1, 2025.

IDV-PSTK-0625-132 1.729987.132 June 6, 2025