# EDGAR Filing Document

**Accession Number:** 0001562565
**File Stem:** 0001562565-26-000035
**Filing Date:** 2026-3
**Character Count:** 2223
**Document Hash:** d5c183c09f11939801bd5b1b9371fa01
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001562565-26-000035.hdr.sgml**: 20260323

**ACCESSION NUMBER**: 0001562565-26-000035

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260323

**DATE AS OF CHANGE**: 20260323

**EFFECTIVENESS DATE**: 20260323

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Fidelity Merrimack Street Trust
- **CENTRAL INDEX KEY:** 0001562565

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0831

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-186372
- **FILM NUMBER:** 26780460

**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 AAA CLO ETF (Series ID: S000099377)

---

|  |  |  |
|:---|:---|:---|
| Class Name           | Ticker Symbol | Class ID   |
| Fidelity AAA CLO ETF | FAAA          | C000269153 |

---

## Series and Classes Contracts Data

### Fidelity AAA CLO ETF (Series ID: S000099377)

| Class ID   | Class Name           | Ticker Symbol   |
|:---|:---|:---|
| C000269153 | Fidelity AAA CLO ETF | FAAA            |

**Supplement to the Fidelity® AAA CLO ETF January 30, 2026 Prospectus**

The following information found in the "Fund Summary" section under the "Purchase and Sale of Shares" heading is no longer applicable.

Shares of the fund are not eligible for purchase by registered investment companies or business development companies to the extent such acquisition is in reliance on Rule 12d1-4 under the Investment Company Act of 1940.

The following information found in the "Shareholder Information" section under the "Additional Information about the Purchase and Sale of Shares" heading is no longer applicable.

Shares of the fund are not eligible for purchase by registered investment companies or business development companies to the extent such acquisition is in reliance on Rule 12d1-4 under the Investment Company Act of 1940.

ACLO-PSTK-0326-100 1.9922615.100 March 23, 2026