# EDGAR Filing Document

**Accession Number:** 0000917286
**File Stem:** 0001133228-26-009161
**Filing Date:** 2026-6
**Character Count:** 12793
**Document Hash:** f5d2c94c1ab6646d6925b6d9d29be8ff
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001133228-26-009161.hdr.sgml**: 20260611

**ACCESSION NUMBER**: 0001133228-26-009161

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20260611

**DATE AS OF CHANGE**: 20260611

**EFFECTIVENESS DATE**: 20260611

**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:** 261082808

**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 Reserves Digital Fund (Series ID: S000105361)

| Class ID   | Class Name                     | Ticker Symbol   |
|:---|:---|:---|
| C000276119 | Fidelity Reserves Digital Fund | FYMXX           |

### Fidelity<sup>®</sup> Reserves Digital Fund /FYMXX
<u>Fund</u><u>/Ticker</u> <br>

### Summary Prospectus<br>

#### June 12, 2026

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| |
|:---|
| Before you invest, you may want to review the fund's prospectus, which contains more information about the fund and its risks. You can find the fund's prospectus, reports to shareholders, and other information about the fund (including the fund's SAI) online at fundresearch.fidelity.com/prospectus/sec. You can also get this information at no cost by calling 1-877-297-2952 or by sending an e-mail request to funddocuments@fmr.com. The fund's prospectus and SAI dated June 12, 2026 are incorporated herein by reference.  |
| ![](logo_2.jpg)<br>&nbsp;&nbsp;&nbsp;&nbsp;<br>245 Summer Street, Boston, MA 02210 |

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

### Fund Summary
Fund:<br>

Fidelity<sup>®</sup> Reserves Digital Fund <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

#### Investment Objective
Fidelity<sup>®</sup> Reserves Digital Fund seeks to obtain as high a level of current income as is consistent with the preservation of capital and liquidity.

#### Fee Table
The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. **You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Shareholder fees** <br>**(fees paid directly from your investment)**<br>

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| | |
|:---|:---|
| **Annual Operating Expenses**<br>**(expenses that you pay each year as a % of the value of your investment)**  | **Annual Operating Expenses**<br>**(expenses that you pay each year as a % of the value of your investment)**  |
| Management fee | &nbsp;&nbsp;0.25%  |
| Distribution and/or Service (12b-1) fees |  |
| Other expenses | &nbsp;&nbsp;0.00% <sup>A</sup>  |
| **Total annual operating expenses** | &nbsp;&nbsp;0.25%  |
| Fee waiver and/or expense reimbursement | &nbsp;&nbsp;0.07%<sup>B</sup>  |
| **Total annual operating expenses after fee waiver and/or expense reimbursement** | &nbsp;&nbsp;0.18% |

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<sup>A</sup> Based on estimated amounts for the current fiscal year.

<sup>B</sup> Fidelity Management & Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.18% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through August 31, 2027. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.

***Summary Prospectus***<sub>2</sub>

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This **example** helps compare the cost of investing in the fund with the cost of investing in other funds.<br>

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

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| | |
|:---|:---|
| 1 year | $18  |
| 3 years | $72 |

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

#### Principal Investment Strategies
• Investing only in U.S. Treasury bills, notes and bonds with a remaining maturity of, or issued with a maturity of, 93 days or less, cash, overnight repurchase agreements fully collateralized by U.S. Treasury bills, notes and bonds, and other registered government money market funds that are compliant with the Guiding and Establishing National Innovation for U.S. Stablecoins Act ("GENIUS Act").

• Investing only in eligible reserve assets that payment stablecoin issuers are permitted to maintain under the GENIUS Act and any regulations adopted thereunder.

• Investing in compliance with industry-standard regulatory requirements for money market funds as well as any applicable GENIUS Act requirements for the quality, maturity, liquidity, and diversification of investments. <br>

#### Principal Investment Risks
• *Interest Rate Changes.*

Interest rate increases can cause the price of a money market security to decrease.

• *Income Risk.*

A low or negative interest rate environment can adversely affect the fund's yield.

• *Issuer-Specific Changes.*

A decline in the credit quality of an issuer can cause the price of a money market security to decrease.

• *U.S. Treasury Obligations.*

U.S. Treasury obligations are high-quality securities issued or guaranteed by the U.S. Treasury providing minimal risk of loss of principal if held to maturity. Fluctuations in interest rates may cause the market value of such securities to vary.

• *Stablecoin Issuer Reserves Risk.*

Fund shares are expected to be held primarily by one or more stablecoin

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| | |
|:---|:---|
| ***3*** | ***Summary Prospectus*** |

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Fund Summary — continued<br>

issuers as all or a portion of the reserve assets that back the stablecoins issued to their customers. Fund assets are therefore expected to fluctuate depending on the creation of additional stablecoins or the redemption of outstanding stablecoins. Stablecoins may face periods of uncertainty or volatility that could result in rapid or unexpected redemption requests. Large redemption requests could negatively affect the fund's liquidity, net asset value or portfolio management. Because the fund intends to invest only in certain eligible reserve assets that payment stablecoin issuers are permitted to maintain under the GENIUS Act, the fund's yield may be lower than other money market funds that are permitted to invest in a wider universe of investments.<br>

*You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Fidelity Investments and its affiliates, the fund's sponsor, is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.*

<br> *The fund will not impose a fee upon the sale of your shares.* 

#### Performance
Performance history will be available for the fund after the fund has been in operation for one calendar year.

#### Investment Adviser
Fidelity Management & Research Company LLC (FMR) (the Adviser) is the fund's manager. Other investment advisers serve as sub-advisers for the fund.

#### Purchase and Sale of Shares
Shares are offered to institutional investors, including stablecoin issuers. <br>

The fund may offer additional share classes in the future that employ blockchain technology to maintain a record of share ownership.<br>

You may buy or sell shares in various ways. Email FDAMIR@fmr.com for more information.

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| | |
|:---|:---|
| **Internet** | **Internet** |
| **institutional.fidelity.com** | **institutional.fidelity.com** |
| **Phone** | **Phone** |
| **To reach a Fidelity representative** <br>**1-877-297-2952** | **To reach a Fidelity representative** <br>**1-877-297-2952** |
| **Mail**  | **Mail**  |
| **&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**<br>**Fidelity Investments** <br>**P.O. Box 770002** <br>**Cincinnati, OH** <br>**45277-0081** | ***Overnight Express:*** <br>***Fidelity Investments*** <br>***100 Crosby Parkway*** <br>***Covington, KY 41015*** |

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The price to buy one share is its net asset value per share (NAV). Shares will be bought at the NAV next calculated after an order is received in proper form.<br>

***Summary Prospectus***<sub>4</sub>

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The price to sell one share is its NAV. Shares will be sold at the NAV next calculated after an order is received in proper form.<br>

The fund is open for business each day the New York Stock Exchange (NYSE) is open.<br>

Even if the NYSE is closed, the fund will be open for business on those days on which the Federal Reserve Bank of New York (New York Fed) is open, the primary trading markets for the fund's portfolio instruments are open, and the fund's management believes there is an adequate market to meet purchase and redemption requests.<br>

Fidelity normally calculates NAV each business day as of 4:00 p.m. Eastern time and, when the New York Fed and principal bond markets are open, as of 5:00 p.m. Eastern time. The fund's assets normally are valued as of these times for the purpose of computing NAV.<br>

The fund has a minimum initial investment of $1,000,000. The fund may waive or lower purchase minimums.

#### Tax Information
Distributions you receive from the fund are subject to federal income tax and generally will be taxed as ordinary income or capital gains, and may also be subject to state or local taxes, unless you are investing through a tax-advantaged retirement account (in which case you may be taxed later, upon withdrawal of your investment from such account).

#### Payments to Broker-Dealers and Other Financial Intermediaries
The fund, the Adviser, Fidelity Distributors Company LLC (FDC), and/or their affiliates may pay intermediaries, which may include banks, broker-dealers, retirement plan sponsors, administrators, or service-providers (who may be affiliated with the Adviser or FDC), for the sale of fund shares and related services. These payments may create a conflict of interest by influencing your intermediary and your investment professional to recommend the fund over another investment. Ask your investment professional or visit your intermediary's web site for more information.

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| | |
|:---|:---|
| ***5*** | ***Summary Prospectus*** |

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Fidelity Distributors Company LLC (FDC) is a member of the Securities Investor Protection Corporation (SIPC). You may obtain information about SIPC, including the SIPC brochure, by visiting www.sipc.org or calling SIPC at 202-371-8300.

Fidelity, the Fidelity Investments Logo and all other Fidelity trademarks or service marks used herein are trademarks or service marks of FMR LLC. Any third-party marks that are used herein are trademarks or service marks of their respective owners.© 2026 FMR LLC. All rights reserved.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1.9922389.100 RDF-SUM-0626

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