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In “Mailbox Rule” Case, Tax Court Finds Later U.S. Postal Service Mark Trumps Earlier Private Postage Meter Mark



Thomas v. Comm’r., T.C. Memo. 2020-33 (2020)

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A recent Tax Court case considered the effect of conflicting postmarks when determining whether a mailed item was timely filed. The IRS had sent a couple a notice of tax deficiency with a March 5, 2018 deadline to file a petition for reconsideration with the Tax Court. On that date, the wife stamped an envelope using a private postage meter, and her husband placed their petition inside, took it to a post office, and dropped the envelope into a mailbox with a 5:00 p.m. last pickup time. When the petition was received on March 12, it had two postmarks—the private postmark of March 5 and a U.S. Postal Service (USPS) postmark of March 6. There was no damage or any indication that delivery was delayed. The IRS sought to dismiss the petition because it was not timely filed; the couple argued it was timely mailed on March 5.

The court explained that, under the “timely mailed, timely filed” rule (sometimes referred to as the “mailbox rule”), an item’s postmark date is deemed to be its delivery date. A document delivered by U.S. mail is considered timely if (1) the envelope is properly addressed to the recipient with sufficient postage, (2) the postmark date falls on or before the deadline, and (3) the document is mailed on or before that date. For private postmarks, the rule applies only if the postmark shows a legible date on or before the deadline and the item is received within the same amount of time as it would have been received if postmarked at the same point of origin by the USPS on the deadline. For items with both private and USPS postmarks, the private postmark is disregarded. Accordingly, despite the couple’s assertion that the petition was placed in the mailbox on March 5, the court concluded that the USPS postmark controls and declined to reconsider the deficiency determination.

EBIA Comment: This case highlights the risks of waiting until the last minute to file—and the lesson applies broadly, including to benefit plan filings. Senders should consider using registered or certified mail to obtain a postmark receipt from the USPS to evidence timely mailing and, therefore, timely filing. For more information, see EBIA’s ERISA Compliance manual at Sections XI.G (“Disputes About Receipt of Paperwork”) and XXII.F.2 (“Form 5500 Is Normally Due Seven Months After End of Plan Year”). See also EBIA’s Cafeteria Plans manual at Section XXXIV.B.2 (“When to File Form 5500”); EBIA’s 401(k) Plans manual at Section XXX.J (“Procedures Involving Receipt of Documentation”); and EBIA’s COBRA manual at Sections XVIII.J (“Sending the Election Notice and Proving It Was Sent”), XIX.C (“Calculating 60-Day Period When Election Notice Is Mailed”), and XXII.A (“Paying the COBRA Premium: Deadlines and Grace Periods”).

Contributing Editors: EBIA Staff.

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