For most nonprofits, the year-end appeal is the biggest mailing of the year. And the window that matters most, late November through December, is also when the Postal Service is at its busiest. USPS’s own target for nonprofit Marketing Mail is 4 to 7 days in the lower 48, and December volume can push it past that.
The good news is that a little planning protects you. Here’s what I recommend:
1) Mail your top donors first class
Send as much of your list as you can by stamped first class mail: at least your top 10 to 20 percent, or donors who gave $100 or more last year. It costs more, but it arrives faster and looks more personal.
2) Drop your nonprofit mail two weeks earlier
Send the Marketing Mail portion of your list about two weeks earlier than you normally would, so it lands in your target window instead of after it.
3) Plan more follow ups
Build in extra multichannel follow ups in case a letter arrives late or never shows up: emails, a second mailing to key donors, postcards, and phone calls.
4) Get ready for late December gifts
In late 2025, USPS clarified that a postmark shows the date mail is first processed by machine, not necessarily the date it was dropped off. A check mailed on December 30 could end up with a January postmark, and that matters to donors counting on a deduction.
- Remind donors in your December emails that the easiest way to make a gift count this year is to give online.
- If donors mail late in December, suggest they ask for a hand-stamped postmark at the post office counter.
- Keep the envelopes for gifts that arrive in early January so you can document the postmark date.
The mail will never be perfectly predictable in December, but these steps give your appeal the best shot at landing on time.