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How do I: prove timely filing of my income tax return?

Proof of filing tax return

A return or a payment that is mailed to the IRS is timely filed or paid if it is delivered on or before its due date. A return with a U.S. postmark, which is delivered after its due date, is timely filed if the date of the postmark is no later than the due date, the return was properly addressed, and the return had proper postage. The timely mailing/timely filing rule also applies when a taxpayer receives a filing extension. If an envelope has a post office postmark and a non-post office postmark, the latter is disregarded and the post office postmark determines the filing date.

Comment. The timely filing, timely mailing rule requires that the return be postmarked within the prescribed filing period. Thus, an individual return postmarked April 16 and received on April 20 is considered filed on April 20.

Private carriers.

A return delivered by a designated private carrier is timely if the carrier marks or records the return no later than the due date of the return. However, a return delivered by means other than the U.S. mail or a designated private carrier must be delivered to the appropriate IRS office on or before its due date to be timely.

The IRS can designate a private carrier if the carrier: is available to the general public; is as timely and reliable as U.S. first class mail; records the date on which the package was given to it for delivery; and satisfies other conditions. The IRS has identified DHL Express, Federal Express, and United Parcel Service as designated carriers.

No postmarks; other postmarks.

If there is no postmark, the taxpayer may establish the mailing date by extrinsic evidence. A return in an envelope with a foreign postmark or private meter machine postmark is timely filed if the postmark is on or before the due date of the return and the return is received no later than if it had been postmarked by the postal service on the last day for filing the return.

Registered, certified.

A receipt showing that a return was sent by registered or certified mail is proof that the return was delivered to the place that it was addressed. Returns sent by registered mail are deemed to be postmarked on the date of registration. Returns sent by certified mail are deemed to be postmarked on the date stamped on the receipt, under the timely mailed, timely filed rule. However, if a taxpayer mails a return certified but does not obtain a certified receipt, the postmark on the envelope determines the filing date.

Comment. A taxpayer mailing a return on or near its due date should use registered or certified mail with a postmarked receipt. Documents sent in this manner are automatically timely filed.


An electronically-filed return with a timely electronic postmark is timely filed, provided that the return is filed in the manner prescribed for electronic returns. An electronic postmark is a record of the date and time, in the taxpayer’s time zone, that an authorized electronic return transmitter receives the e-filed document on its host system.


If and only to the extent that this publication contains contributions from tax professionals who are subject to the rules of professional conduct set forth in Circular 230, as promulgated by the United States Department of the Treasury, the publisher, on behalf of those contributors, hereby states that any U.S. federal tax advice that is contained in such contributions was not intended or written to be used by any taxpayer for the purpose of avoiding penalties that may be imposed on the taxpayer by the Internal Revenue Service, and it cannot be used by any taxpayer for such purpose.