We want to make you aware of an important clarification from the U.S. Postal Service that may affect tax filing deadlines.
USPS Postmark Definition Update
USPS now defines a postmark as the date a mail piece is first processed by automated equipment at a USPS facility—not the date it is dropped off. As a result, the postmark reflects the processing date rather than the mailing date.
Impact on Tax Filings
Under the IRS “mailbox rule” (IRC §7502), a timely postmark is used to determine whether a tax return or payment was filed on time. If you mail a return or payment on April 15 but it is not processed until April 16, the postmark may show April 16 and could be considered late.
How to Avoid Issues
To reduce the risk of penalties or interest, we recommend:
- Requesting a hand-stamped postmark at a USPS retail counter on the day you mail the item.
- Using Certified Mail or Registered Mail, which provide a dated receipt as proof of mailing.
- E-filing returns or making electronic payments for time-sensitive deadlines to eliminate postmark uncertainty.