USPS postmarks can lag mailing dates. What taxpayers and voters should know
USPS postmark dates may differ from mailing dates, affecting Oct. 15 tax filings and mail ballots with state-specific deadlines.
Key points
- USPS postmark delays from a December 2025 rule could affect tax returns and mail-in ballots.
- Most states require absentee ballots to arrive by Election Day, regardless of postmark date.
- USPS plans extraordinary measures from Oct. 24 to speed up mail-in ballot delivery.
U.S. Postal Service postmark practices formalized in a December 2025 rule could mean longer delays between when mail is sent and when it is postmarked, affecting time-sensitive documents like tax returns and mail-in ballots. The issue arises as the Oct. 15 federal tax filing extension deadline and the Nov. 3 midterm elections approach.
Taxpayers who mail returns can meet the deadline by getting a manual postmark at the post office. However, voters casting mail-in ballots cannot necessarily rely on the same rule.
State rules for mail-in ballots
Most states require mail-in ballots to arrive by Election Day, regardless of when they were mailed or postmarked. According to the National Conference of State Legislatures, 35 states require mailed absentee ballots to be received on or before Election Day. The other 15 states, along with Washington, Guam, Puerto Rico and the Virgin Islands, generally allow ballots postmarked by Election Day to arrive afterward, usually within a specified number of days.
Katty Owens Hubler, director of elections and redistricting for the NCSL, said, "State laws govern elections for the most part, and every state has chosen a little bit different way of doing things."
State laws govern elections for the most part, and every state has chosen a little bit different way of doing things.
— Katy Owens Hubler
USPS measures and advice
In 2024, nearly 48 million voters cast absentee ballots, about 30% of the total 158.2 million ballots, per the U.S. Election Assistance Commission. About 1.2% of mail-in ballots were rejected; 40.7% of those due to signature mismatches or incomplete signatures, 10% for missing signatures, and 17.8% for arriving after the state deadline.
Starting Oct. 24, USPS plans "extraordinary measures" to speed up mail-in ballot delivery, including additional deliveries to election offices. From Oct. 26, postal workers will hand-postmark ballots delivered to local election offices or routed through hubs. Tammy Patrick, chief programs officer at the National Association of Election Officials, said, "These things are going above and beyond what the Postal Service does for other pieces of mail."
Patrick advised voters to mail ballots a week before the deadline. If closer to Election Day and in a state that allows postmark to establish timeliness, voters can request a hand-postmark at any post office. Taxpayers filing online avoid the issue; those mailing returns should request a manual postmark or use certified mail.
