Effective  December 24, 2025 the United States Postal Service “USPS” postmark will no longer reflect the day you dropped the mail off at a post office or a blue collection box; the date on your mail now reflects when it is first processed at a regional sorting facility. This means mail can be postmarked a day or more after you drop it off, which can mean missed deadlines.

The USPS acknowledges that the date differences between drop-off and postmark will become more common and states the update:

• Aligns with its Delivering for America cost-cutting and modernization plan, which consolidates processing in fewer facilities.
• As a result of the USPS reduction in transportation trips between local post offices and sorting hubs, mail may sit for a day or more before being processed and postmarked.

Why this matters:

• The IRS continues to apply the “timely mailing as timely filing.” This means that if a tax return or payment is postmarked by the U.S. Postal Service (USPS) or a designated private delivery service (PDS) on or before the due date, it is considered timely filed—even if it is received after the deadline, as long as all requirements are met.
  • A delayed postmark could mean:
    • Late filing penalties
    • Interest charges
  • If a bill requires a payment to be postmarked by a certain date you could be marked late even if drop it off on time.
  • This not only affects tax returns and estimated tax payments but other date sensitive items such as election ballots, real estate tax payments, and other legal documents.
  • Rural communities might be more affected because:

• • Mail often travels farther to reach a processing hub.
  • Fewer daily transportation trips mean longer waits before processing.

How to protect yourself if use USPS:

• Mail time sensitive items earlier, 2-3 days before the deadline
• Go to the post office counter and ask for a hand stamped postmark – a “retail acceptance” postmark.
• • USPS says machine postmarks are standard, but counter service can still provide same‑day acceptance.
• Use tracking for important documents.
• Avoid using blue collection boxes for deadline‑critical mail, especially after pickup times.

Insure you meet IRS filing requirements:

• Only specific services from designated private delivery services (such as FedEx, UPS, and DHL services listed by the IRS) qualify for the timely mailing rule. The date recorded or marked by the PDS is treated as the postmark date.
• For USPS mail, the postmark must be dated on or before the due date. If the postmark is after the due date, the document is considered filed when received, not when mailed.
• If sent by registered or certified mail, the date of registration or the postmark on the sender’s certified mail receipt is treated as the postmark date, providing evidence of timely mailing.
• For electronic filings, the electronic postmark from the authorized transmitter is the filing date, and the taxpayer’s time zone controls if different from the transmitter’s.
• If the envelope is missing or lacks a postmark, the taxpayer may use other evidence to prove timely mailing, but the burden of proof is on the taxpayer.

Conclusion:

Plan accordingly to mail your date sensitive documents so they are deemed to be “timely mailed/filed.”  We encourage our clients to make tax payments electronically instead of by mail. In the near future, the United States Department of Treasury is going to require all tax payment to be electronically in the near future.

If you need further assistance or have any questions, please contact your Polk and Associates advisor.

Polk & Associates

Large enough to serve a diverse clientele, yet small enough to maintain a hands-on approach, we are committed to maintaining the highest accounting and ethical standards with continuous education, extensive research resources, and excellent quality control.

Polk and Associates is a member of the Michigan Association of Certified Public Accountants, and the American Institute of Certified Public Accountants. The firm participates in the AICPA Peer Review Program, and has always received the highest level of award for its audit practice and quality control.