The USPS recently changed its postmark system (effective Dec. 24, 2025), clarifying that machine postmarks now reflect the date of first automated processing at a regional facility, not when mail was dropped off, potentially delaying the postmark date by several days. This impacts time-sensitive items like tax documents and ballots, so for proof of mailing, customers should now request a manual hand-stamped postmark at a retail counter or use Certified/Registered Mail, as the old postmark date isn’t a reliable indicator of mailing time anymore.
Key Changes & Implications
- Processing vs. Deposit Date: The machine-applied postmark now shows when mail starts its journey at a regional sorting center, not when you deposited it in a mailbox.
- Impact on Deadlines: This shift means items mailed just before a deadline (like tax payments or legal filings) might get a postmark dated after the deadline, potentially making them late.
- Why the Change? It’s part of the Delivering for America (DFA) plan to consolidate processing networks, making the old system less aligned with operations.
How to Ensure Timely Mailing
- Request a Manual Postmark: Take time-sensitive mail to a USPS retail counter and ask for a free, local, hand-stamped postmark on the acceptance date.
- Use Other Services: Opt for Certified Mail, Registered Mail, or a Certificate of Mailing for official proof of mailing.
- Mail Early: Send important documents several days before the deadline to account for potential processing delays.
