A subtle change at the U.S. Postal Service is creating an unexpected year-end risk for nonprofits—and many leadership teams haven’t addressed it yet.
In August 2025, the USPS announced updated guidance on postmarking and stated that its procedures were “unchanged.” In practice, however, the agency now applies many postmarks at regional processing centers rather than local post offices. As a result, mail often receives a postmark one or more days later than when a donor drops it in the mailbox.
Why This Matters for Nonprofits
This change matters because the IRS uses the postmark date—not the check date and not the receipt date—to determine when a charitable contribution is made.
Consequently, a donation mailed in late December can receive a January postmark and legally count toward the next tax year. That outcome creates risk across several fronts —
- Donor expectations around year-end tax deductions
- Accurate contribution reporting
- Audit readiness and internal controls
- Avoidable donor confusion or dissatisfaction
A Real-World Example
Consider a common scenario. A donor drops a check into a mailbox outside their local post office at 4:30 p.m. on December 31. Historically, that action likely resulted in a same-day postmark.
Today, however, USPS operations often route that mail to a regional facility first. As a result, the postmark may not appear until January 2 or 3.
Same donation. Different tax year.
What Nonprofit Executives Should Do Now
This issue is not merely administrative. Instead, it affects governance, controls, and donor trust. For that reason, nonprofit executives should take several practical steps now:
- Document clear procedures for handling year-end mailed gifts
- Retain envelopes with legible postmarks for all mailed contributions
- Review early-January mail carefully for December postmarks
- Avoid using check dates to establish contribution timing
- Confirm auditors test year-end donations as part of their procedures
Together, these steps reduce ambiguity and strengthen compliance.
The Strongest Recommendation: Encourage Electronic Giving
Even with better procedures, mailed donations now carry more risk. Therefore, the most effective solution is to encourage electronic giving whenever possible.
Electronic contributions —
- Eliminate postmark uncertainty
- Provide immediate confirmation to donors
- Improve cash flow predictability
- Strengthen internal controls
- Reduce administrative workload
Accordingly, this is an ideal time to revisit donor communications, year-end appeals, and giving page language.
A Timely Reminder for Boards and Leadership Teams
Although this issue may sound technical, its impact is very real—especially at year-end, when donor expectations peak and audit scrutiny increases.
Now is the moment for nonprofit leaders to educate donors, review internal policies, and reinforce procedures. Ultimately, clarity, consistency, and documentation protect both your organization and your donors.
It is also worth noting that these new USPS processes may have broader implications, including for the mailing and postmarking of election ballots.
Dan Weiss, founder and President of Counterpart CFO, leads a team of flexible, part-time CFOs specializing in nonprofits. To read more from Dan, follow him on LinkedIn or subscribe to his blog at www.counterpartCFO.com.