Donors planning to mail charitable contributions before the end of 2025 will want to take note of a new U.S. Postal Service (USPS) rule that may affect your postmark date and this year’s tax deductions.

Beginning Dec. 24, 2025, USPS will apply postmarks at regional processing centers, at which it could take a mailed donation several days to arrive. That means if you mail your donation in late December, it may not be postmarked until January 2026. Under IRS rules, your donation must be postmarked by Dec. 31, 2025, to qualify for a 2025 tax deduction.

 If you plan to donate before year-end, consider these tips:

• Think about donating securely online instead to ensure immediate receipt of your transaction.
• If mailing your contribution, avoid self-service kiosks, dropping in your own mailbox or a blue box collection site, and carriers like UPS or FedEx. Instead, visit your local post office in person and:
  • Ask for a manual time stamp from the USPS employee.
  • Buy postage at the counter; a Postage Validation Imprint (PVI) label shows the date of purchase/mailing.
  • Mail via certified or registered mail for a dated receipt.

If your mail isn’t postmarked in time this year, it might be considered for your 2026 deduction, so all is not necessarily lost. But keep in mind this new rule applies to any time-sensitive documentation (legal documents, IRS forms and payments, etc.) moving forward, not just your year-end charitable donations.