What the New USPS Postmark Rule Means for End-of-Year Giving
On December 24, 2025, a new United States Postal Service rule took effect that will affect mailings, which, while for most things is a minor change, could have a significant impact on year-end giving.
Under the new rule, a postmark describes the date on which the Postal Service processes the mailing, not the date on which the Postal Service first accepts possession. For example, you may drop off a piece of mail on Tuesday at 4:00pm, but the Post Office may not process it until Wednesday at 9:00am. Under the new rule, the postmark date would then reflect the Wednesday date—the date on which the mailing was processed. CapDev Senior Counsel, Jennifer Hanes Sullivan points out, “this issue came up with a client this week.” Nonprofits and donors alike should be aware of what this means for mailed donations, “since for decades it has been shared that best practice on the legal date a nonprofit should use as the date a gift is received is the postmark date/legal date of transfer,” adds Hanes Sullivan. Read below to see recommended steps for nonprofit organizations and donors to remain proactive in their respective philanthropic efforts.
For nonprofit organizations
- This is a great opportunity for donor education. Consider adding language to your year-end appeals, such as: “To ensure a 2026 charitable deduction, please mail gifts early or use a trackable or electronic method.” Be sure to also include similar language on your website.
- For mail that is processed manually, save the physical envelopes (or scanned copies) with the donation, clearly showing postmark dates.
- For mail processed through a lockbox or other automated method, be sure that your processor scans full envelopes with clear postmarks.
- Your finance or development team should specifically review donations received in the weeks after year-end. Remember, nonprofits should NOT use check dates to determine in which fiscal year to record donations, as checks can be backdated.
- Document supporting year-end gift recording, as financial statement audits often test revenue cutoffs as part of their process.
For donors
- Ask for a hand-stamped postmark at the Post Office to ensure the actual mailing date is recorded.
- Buy your postage at the counter, as the printed labels include the correct acceptance date.
- Use certified or registered mail, which again, provides official evidence of the mailing date.
Review the full USPS ruling here.
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