Final rule · 2025-20740

Postmarks and Postal Possession

The Postal Service is adding section 608.11, "Postmarks and Postal Possession," to the Domestic Mail Manual (DMM). This new section defines postmarks, identifies the types of Postal Service markings that qualify as postmarks, and describes the circumstances under which those markings are applied. It also advises customers of how to obtain evidence of the date on which the Postal Service accepts possession of their mailings. This new language in the DMM does not change any existing postal operations or postmarking practices, but is instead intended to improve public understanding of postmarks and their relationship to the date of mailing.