We want to share an important update for taxpayers who mail tax returns, payments, or other time-sensitive tax documents close to filing deadlines. Effective December 24, 2025, the U.S. Postal Service issued a Final Rule clarifying how postmarks are applied and how customers can document the date USPS accepted a mailing. Under this guidance, postmarks may be applied at regional processing centers rather than at the local post office where mail is dropped off. In addition, pre-printed postage, such as meter strips, Click-N-Ship labels, or kiosk labels, does not by itself prove when USPS accepted an item. As a result, the postmark date on a mailed item may be later than the date it was deposited.
Why This Matters
For tax filings where timeliness is determined by the mailing date, relying solely on a postmark or metered postage may result in the IRS treating a filing as late, even if it was mailed on the due date. If you choose to mail documents close to a deadline, we strongly recommend one of the following:
- Presenting the mail in person at a U.S. Post Office counter and requesting a manual postmark
- Using Certified Mail or obtaining a USPS Certificate of Mailing
- Using an approved private delivery service (such as FedEx or UPS) that meets IRS requirements
Please avoid relying on mailbox drop-offs, after-hours mail slots, or metered postage alone for deadline-day filings. Whenever possible, electronic filing remains the safest and most reliable option, especially near filing deadlines.
In Your Corner
If you have questions about acceptable mailing methods or would like assistance planning ahead for upcoming deadlines, please don’t hesitate to reach out to your LGA advisor or contact us. We’re happy to help ensure your filings are handled properly and on time.
