New USPS Rule — Beginning December 24, 2025 to ensure your charitable donation is recognized as tax deductible on the day it is mailed with the USPS, you must go into the Post Office and request a manual same-day postmark.

The IRS and State tax authorities use the postmark date to establish when a mailed tax payment or return has been paid or filed AND, charitable donations sent through the mail are also treated as made on the postmark date. The new USPS rule, now in effect, clarifies that machine postmarks will be added at regional distribution centers NOT local drop-off points. This means that there could be a several day delay between someone dropping their check in the mail and the envelope receiving the postmark that determines whether your tax return is on time and whether your donation to a charity can be counted on that tax return as a charitable contribution in 2025 or 2026!