Recent Post Office Changes May Impact Timely Tax Filings
By Gabriel Mkhitarian, Tax Senior
For decades, taxpayers across the U.S. have relied on a simple understanding of what is considered “timely filed” under IRS (and state tax) rules. Taxpayers have followed the Internal Revenue Code Section 7502 that treated paper-filed returns, payments and other documents as timely filed if they had been postmarked on or before their due date. The IRS allowed the date mailed rather than the date received by the IRS to be treated as the filing date.
Postmarks have routinely been associated with the date on which the Postal Service receives the mail piece, such as a paper-filed tax return. In this context, postmarking historically represented the date the return was dropped off at the post office. As long as that date was on or before the filing deadline, the IRS would accept the filing as timely.
A new rule, implemented by the Postal Service on December 24, 2025, formally clarified that postmarking should no longer be associated with the post office location or date on which mail is received, but rather with the location of the processing center and date on which it is processed. As a result, mail may be processed in a different location than where it was originally received, and potentially at a later date. The Postal Service is utilizing more regional processing centers, which may be located far from your local post office branch, potentially resulting in mail not being postmarked on the day it was received. Thus, in a hypothetical scenario involving a last-minute paper filing, a return dropped at a local post office on April 15 and postmarked that day at the local branch would previously have been considered timely filed by the IRS. Under the new rule, however, timeliness depends entirely on when the post office processes the mail. For example, if the return is processed on April 16, the IRS will no longer recognize it as timely filed, potentially causing the taxpayer to owe interest and penalties.
Taxpayers have several options to address the Postal Service’s policy of utilizing regional processing centers:
- File Tax Returns Electronically – The best solution is to file tax returns electronically and make payments electronically as well, thereby avoiding the hassle of mailing physical paper copies. Electronic filing is safe, reliable and items are processed by the IRS considerably faster and more accurately than traditional paper filing.
- Certificate of Mailing, Meter Label or Manual Postmark – If paper filing is unavoidable, taxpayers may purchase a certificate of mailing, buy a “postage validation imprint” (meter label) at the counter or request a manual postmark. All three options ensure that the postmark reflects the date of acceptance but only the first provides you with actual proof of mailing. If the return is delivered to the post office on the deadline date, that is the date that will appear on the postmark. The downside of these options, however, is that a physical visit to the post office is required.
- Certified or Registered Mail – Additionally, taxpayers may use certified or registered mail. These options not only confirm the exact date the mail was received by the Postal Service, but also allows taxpayers to track the shipment and monitor its delivery to the recipient. On the flip side, like the options above, these methods also require an in-person visit to the post office.
As an alternative, the IRS allows taxpayers to use specific private delivery services (Private delivery services) to comply with the timely mailing/timely filing rule.
Note that buying postage from a self-service kiosk, Click-N-Ship online postage and meter strips are not accepted by the IRS as proof of timely mailing.
Taxpayers using the Postal Service to deliver tax filings and other time-sensitive documents such as bill payments, voting ballots or year-end charitable donations (needing a Dec. 31 postmark) should consider the available alternatives to obtain proof of mailing.
We recommend electronic filing as the most effective method for mitigating this newly emerging issue and encourage you to contact us to learn more about electronic filing and its benefits.
