The California Franchise Tax Board (FTB) issued an important announcement this morning. The USPS has adjusted its transportation operations effective December 24, 2025, which may delay mail delivery to processing facilities. While postmarking practices remain unchanged, the postmark date could differ from the day you drop off your mail. This may impact time-sensitive items such as tax returns and payments. You may recall that the postmark for tax returns filed on paper must be on or before the due date. That date for personal income tax returns is April 15th, unless you file a timely extension. Tax payments must also be postmarked by the due date; otherwise, they are considered late.
While the FTB issued this notice, the information applies to returns and payments sent to the IRS and state tax agencies. Do NOT count on mailing a return on the due date and expect it to be postmarked that day without standing in a long line for a manual postmark! This warning also applies to property tax payments, which always have a postmark deadline.
To avoid having a late filed tax return, tax payment, or other filing, taxpayers should consider:
- Mail returns and payments several days before the deadline.
- Request a manual postmark at the post office, use certified mail, or obtain a certificate of mailing for proof of mailing.
- File electronically or make online payments by the due date. Due to processing delays by tax agencies near the filing deadline, online payments are advisable. They are immediate, and you receive confirmation on-screen and, if requested, also by email.
- Respond to notices directly through the tax agency website when possible.