Mailing a Donation on December 31? Here’s What to Know and What to Do

It’s the holiday season and many donors are planning to make charitable gifts before ringing in the New Year. U.S. Postal Service (USPS) guidance effective December 24, 2025 clarifies that postmarks are generally applied by machine at regional processing facilities rather than at local post offices. This means that mail items may not be postmarked until one or more days after they are deposited in the mail. Therefore, donors intending to make year-end charitable donations by check should get documentation of the postmark date by bringing envelopes containing their gift checks to the counter at a post office and requesting either:

• Certified/Registered Mail
• A Postage Validation Imprint (PVI)
• A Certificate of Mailing
• A manual/local postmark free of charge

The “Mailbox Rule”

According to federal tax guidance, donations made by check and mailed through the USPS are generally considered made on the date mailed (this policy is known as the “mailbox rule”). Therefore, if a gift is being made at year-end or is otherwise time-sensitive, it is important to document the date it was mailed. Per USPS policy, a postmark may not be applied until several days after a gift is mailed; the postmark date may thus be after the year-end or other deadline even though the gift was mailed on or before that deadline. However, a donor may obtain a postmark on the mailing date by going to a post office and requesting one of the alternatives listed above. It is also important to note that a postal indicia from a meter shows when postage is printed and is not considered a postmark.

The IRS has not issued clear guidance on whether the mailbox rule applies to charitable gifts sent via private delivery services such as UPS or FedEx or to charitable distributions made by private foundations. We therefore encourage donors using private delivery services and private foundations making distributions to charities to obtain confirmation of actual delivery to the charity before the year-end or other deadline.

As we approach the end of the calendar year, we recommend that donors looking to make last-minute, year-end charitable gifts by check bring their donations to the post office as soon as possible and adopt the general best practice of mailing them via certified mail, return receipt requested.

For a qualified charitable distribution (QCD) from an individual retirement account (IRA) to be counted towards a donor’s current year required minimum distribution (RMD), the funds must come out of the IRA by the RMD deadline, generally December 31. Therefore, it is important to request a QCD well before year-end, have the IRA custodian send the check or transfer the funds directly to the charity if possible, follow up with the charity before year-end to be sure it has received and processed the donation, and confirm with the custodian that the QCD funds have left the IRA.

Contact Us

For more information on year-end giving, please contact a member of our Nonprofit Group, or the authors of this advisory.