What Is the IRS Postmark Rule for Tax Deadlines?

Understanding tax submission rules can prevent costly penalties. The Internal Revenue Service (IRS) has a “timely mailing as timely filing” rule for taxpayers who mail documents and payments. Often called the postmark rule, it dictates that the date of the postmark on your envelope can be considered the date of filing or payment, even if the IRS receives it after the deadline.

Scope of the Timely Mailing Rule

The foundation of the postmark rule is in Internal Revenue Code Section 7502. For this rule to apply, the envelope must be properly addressed to the correct IRS office, have sufficient prepaid postage, and be postmarked by the United States Postal Service (USPS) or an approved service on or before the deadline. The sender assumes the risk that the postmark will be timely.

This provision applies to documents like tax returns, amended returns, and claims for a credit or refund. It also extends to tax payments. The rule is designed for mail delivered after the due date; if a document arrives on or before the deadline, its delivery date becomes the official filing date.

This rule does not apply to all tax-related mailings. For instance, certain federal tax deposits, particularly those of $20,000 or more from businesses required to make deposits more than once a month, are not covered. Those payments must be made through other specified methods to be considered timely.

Approved Delivery Services

The timely mailing rule is not limited to items sent through the USPS. The IRS also authorizes specific services from certain private delivery companies, known as Private Delivery Services (PDS). When using a PDS, the date recorded by the company on the package is treated as the postmark date.

The IRS maintains a list of designated PDS and the services that qualify, which include:

• FedEx: First Overnight, Priority Overnight, Standard Overnight, 2 Day, International Next Flight Out, International Priority, and International Economy.
• UPS: Next Day Air Early, Next Day Air, Next Day Air Saver, 2nd Day Air, 2nd Day Air A.M., Worldwide Express Plus, and Worldwide Express.
• DHL Express: Express 9:00, Express 10:30, Express 12:00, Express Worldwide, Express Envelope, Import Express 10:30, Import Express 12:00, and Import Express Worldwide.

Using a non-approved service, even from a designated company like FedEx or UPS, will void the timely mailing rule protection. For example, sending tax documents via FedEx Ground or UPS Ground would mean the filing date is the date the IRS receives the package, not the date it was shipped. Taxpayers must ensure they select one of the explicitly listed services to have their shipment date treated as the filing date.

Proving the Mailing Date

A legible postmark is the primary evidence of timely mailing. To protect against unreadable postmarks or lost mail, taxpayers can use USPS Registered Mail or Certified Mail for definitive proof of mailing.

When using Registered Mail or Certified Mail, the date on the official receipt issued by the postal employee serves as prima facie evidence of mailing. This receipt is accepted as conclusive proof of the postmark date, eliminating ambiguity from a smudged or illegible postmark. This receipt should be retained with your tax records as proof of timely filing.

If a document sent by Registered or Certified Mail is lost and never delivered to the IRS, the mailing receipt can also serve as proof of delivery. By providing the dated receipt, a taxpayer can establish that the document was properly mailed on a specific date, which can protect them from penalties.