Federal Register Notice of Additional Postmarking Information

December 31, 2025

On Tuesday, Aug. 12, 2025, the Postal Service filed a notice in the Federal Register with a proposal to add new language to the Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM). Specifically, the Postal Service proposes to add Section 608.11, “Postmarks and Postal Possession.” The proposed DMM addition does not signal a change in postmarking procedures.

This proposed language will serve multiple purposes. It will define postmarks, identify the types of Postal Service markings that qualify as postmarks, and describe the circumstances under which those markings are applied. It will also explain that, while the presence of a postmark (also known as a “cancellation”) on a mailpiece confirms that the Postal Service was in possession of the mailpiece on the date of the postmark's inscription, the postmark date does not inherently or necessarily align with the date on which the Postal Service first accepted possession of a mailpiece. In addition, the proposed DMM language provides customers with the options available if they want evidence of the exact date on which the Postal Service first accepted possession of their mailpiece.

As stated, the Postal Service’s postmarking procedures are unchanged. Postmarks and cancellations will continue to be applied to single-piece First Class Mail pieces, both letter-shaped and flat-shaped, in the same manner and to the same extent as before.

The Postal Service plans to engage in customer outreach and education efforts beyond the current notice and rulemaking proceeding. Recommendations regarding the Postal Service’s efforts — for instance, how to best reach the public, and/or any particular segments of the public — are welcome.

The full notice and information on how to submit comments are available here: Federal Register :: Postmarks and Postal Possession. Comments are due by Sept. 11, 2025.