Mail your taxes earlier
If you’re mailing 2026 tax returns, the effective postmark deadline moved up — returns must be mailed by April 9 under updated USPS postmark rules, while the standard online filing deadline remains April 15; applying online is the fastest way to get an extension. (centraloregondaily.com) (en.as.com)
The Postal Service added section 608.11, “Postmarks and Postal Possession,” to the Domestic Mail Manual via a final rule published in the Federal Register that became effective Dec. 24, 2025. (govinfo.gov) The DMM addition formally defines what counts as a USPS postmark and explains that a postmark’s inscription “does not inherently or necessarily align” with the date the Postal Service first accepted possession of a mailpiece. (govinfo.gov (rsmus.com) USPS told the public in August 2025 that the proposed DMM language “does not signal a change in postmarking procedures” while the final rule also described how customers can obtain evidence of the date USPS accepted their mail, including requesting a manual postmark at retail. (about.usps.com) State tax agencies have issued advisories in response to the new DMM language; Oregon’s Department of Revenue has publicly urged filers to mail paper returns earlier and to request manual postmarks at retail units if they need firm proof of a mailing date. (oregon.gov) Federal tax law treats the postmark date as the filing date under 26 U.S.C. §7502, and Treasury regulation 26 CFR §301.7502‑1 implements the IRS “mailbox rule,” with Registered or Certified Mail (and designated private delivery services) creating prima facie evidence of timely delivery. (law.cornell.edu (ecfr.gov) Tax and accounting firms advise paying for or requesting a manual postmark at a retail counter, using Certified or Registered Mail, or using an IRS‑designated private delivery service to strengthen proof of timely mailing, because automated processing and network consolidation can cause postmarks to reflect later processing dates. (forvis.com (grantthornton.com)
