Effective December 24, 2025, USPS DMM 608.11 clarifies that a processing-facility postmark normally shows the date of first automated processing. That date may be later than the date USPS first possessed the mailpiece.
What the clarification changes
| Situation | What the visible date may mean | Safer action |
|---|---|---|
| Mail dropped in a collection box | First automated processing may occur later | Do not assume the postmark equals deposit time |
| Mail handed to a retail clerk | Machine mark can still reflect processing | Ask for a manual postmark if the date matters |
| Deadline-sensitive filing | Recipient may apply its own proof rule | Check that rule before mailing |
| Need proof of mailing | A postmark may not be the required evidence | Consider Certificate of Mailing or another appropriate service |
How to request a dated manual postmark
- Prepare the addressed, correctly paid mailpieces.
- Take them to a staffed USPS retail counter before the date deadline.
- Request a manual postmark with the desired current date; USPS guidance allows a free request for up to 50 eligible pieces.
- Ask about a formal proof-of-mailing service when the consequences of a date dispute are significant.
- Keep receipts and copies required by the receiving organization.
Legal and tax deadlines
A USPS rule cannot decide what a court, tax authority, election office or private contract accepts as timely proof. Confirm the recipient’s standard and use a service that creates the evidence it requires.
Related guides
Sources and verification
Facts on this page were checked on August 31, 2026. Dynamic inventory, prices and USPS rules can change.