# EDGAR Filing Document

**Accession Number:** 0000917286
**File Stem:** 0000917286-25-000136
**Filing Date:** 2025-9
**Character Count:** 2253
**Document Hash:** 13bfb6ab2c3965914b2cc18b652aed5e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000917286-25-000136.hdr.sgml**: 20250922

**ACCESSION NUMBER**: 0000917286-25-000136

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250922

**DATE AS OF CHANGE**: 20250922

**EFFECTIVENESS DATE**: 20250922

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** FIDELITY HEREFORD STREET TRUST
- **CENTRAL INDEX KEY:** 0000917286

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

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-52577
- **FILM NUMBER:** 251329213

**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

## Series and Classes Contracts Data

### Fidelity Treasury Digital Fund (Series ID: S000089156)

| Class ID   | Class Name      | Ticker Symbol   |
|:---|:---|:---|
| C000255665 | Liquidity Class | FYHXX           |
| C000261149 | OnChain         | FYOXX           |

**Supplement to the Fidelity® Treasury Digital Fund Liquidity June 28, 2025 Summary Prospectus**

The following information replaces similar information found in the "Fund Summary" section under the "Principal Investment Strategies" heading.

* Normally investing at least 99.5% of total assets in cash and U.S. Treasury securities. The fund intends to invest only in cash and U.S. Treasury securities with a remaining maturity of 93 days or less or issued with a maturity of 93 days or less. 

TDL-SUSTK-0925-100 1.9921545.100 September 22, 2025

**Supplement to the Fidelity® Treasury Digital Fund OnChain**

**July 25, 2025 Summary Prospectus**

The following information replaces similar information found in the "Fund Summary" section under the "Principal Investment Strategies" heading.

* Normally investing at least 99.5% of total assets in cash and U.S. Treasury securities. The fund intends to invest only in cash and U.S. Treasury securities with a remaining maturity of 93 days or less or issued with a maturity of 93 days or less.

TDLO-SUSTK-0925-100 1.9921547.100 September 22, 2025