Some taxpayers still like filing taxes through the mail rather than electronically. It’s a small group — fewer than 10% of all filers — but the practice is still allowed. If you’re one of that group, you’ll want to know what your deadline is. April 15 is the standard IRS due date for your annual tax filing, but that doesn’t mean the IRS has to receive it by then. It just means the envelope has to be postmarked by that date. Briefly, a postmark is an official USPS mark that cancels the stamp and indicates the time the envelope was received by the post office.
But how soon after you mail your return does it receive the postmark? That’s what the new guidance addresses. The USPS emphasizes it is not making any changes, just clarifying when an envelope gets its postmark. The new guidance says: “…while the presence of a postmark on a mailpiece confirms that the Postal Service was in possession of the mailpiece on the date of the postmark’s inscription, the postmark date does not inherently or necessarily align with the date on which the Postal Service first accepted possession of the mailpiece.”
What does this all mean?

In brief, you may mail an envelope on a certain date, but it may not get a postmark until the next day in some instances, so you will have no proof you actually mailed it when you said you did. Fortunately, by adding another step, you can avoid this problem. The USPS advises “customers to request a manual (local) postmark at a retail location if they want to ensure that their mailpiece receives a postmark containing a date that aligns with the date on which the Postal Service first accepted possession of their mailpiece…”
That is, if you take a few extra minutes and go to the post office counter, a USPS employee can manually add the postmark (or provide other proof) right in front of you. Problem solved! What if you use a private service, like FedEx? The IRS has you covered on that, and even provides specific guidance for getting proof.
This is just a summary of over 9,000 words of technical guidance. To avoid the problem altogether, mail your return well in advance or, even better, file electronically. A qualified tax preparer can not only prepare your return but also file it electronically on your behalf, saving a lot of time and headaches.
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