The Tennessee Department of Revenue has issued Notice #26-09 to alert taxpayers and practitioners to upcoming changes in how the U.S. Postal Service (USPS) applies postmarks, which could affect whether mailed tax filings are considered timely.
Effective December 24, 2025, USPS postmarks will generally reflect the date an item is first processed at a postal facility, not necessarily the date it was dropped off or placed in a mailbox.
What This Means for Tennessee Taxpayers
Under Tennessee law, the Department of Revenue determines the timeliness of mailed tax returns and payments based on the postmark date. While the law itself has not changed, the USPS operational change may result in documents being postmarked after a statutory deadline – even if mailed on time.
For example, a return due April 15 that is placed in a mailbox on April 15 but not processed until April 17 would be considered late and subject to penalties.
Department Recommendations
To avoid potential issues, the Department strongly encourages taxpayers to:
- File and pay electronically through the Tennessee Taxpayer Access Point (TNTAP)
- Mail documents well in advance of deadlines if paper filing is necessary
- Request a manual postmark or use certified or registered mail when filing close to a due date
Learn More
Additional guidance is available at www.tn.gov/revenue by clicking on Revenue Help.
