USPS Changes Postmark Rules

USPS updates postmark guidelines: What to know

Learn how USPS postmark changes may affect delivery of ballots, bills, and important documents, prompting the need for early mailing.

The United States Postal Service has changed the postmark process going into 2026, which potentially could add late fees and penalties for anyone mailing time-sensitive documents like tax documents or bill payments.

For decades, the postmark – an official mark that shows where and when mail was accepted by the Postal Service – has been used in law as proof that an individual met a deadline, such as submitting a ballot by Election Day.

A USPS postmark once indicated the date when mail was dropped in a mailbox or submitted at the post office counter. Now, USPS is clarifying in a new rule that the postmark will reflect the date an envelope is first processed by an automated USPS sorting machine, potentially days after it was dropped off – not the actual drop-off date.

The cost for stamps won’t change, but the price of priority shipping will see an increase at the top of the year.

Here’s what you need to know about the change in mailing.

USPS postmark changes rules

The new USPS postmark rule went into effect on Dec. 24, 2025, and affects all mail dropped in a mailbox or blue postal boxes where postmarks are applied at regional sorting facilities. This effectively changes the date that the mailer processes the parcel, not when you mailed it as previously.

Tax payments, charitable contributions, legal filings, rent payments and other bills or items that rely on postmark dates for deadlines can be impacted by later postmarks and risk late fees, penalties or delinquency.

With the new rules, time-sensitive mail should be mailed several days before the deadline or shipped directly from the post office with a stamped postmark when it was mailed.

USPS postal shipping costs to increase

The new increase in USPS shipping rates is set to take effect as of Jan. 18, 2026. Prices are based on the package’s weight and the distance it is being shipped.

Priority Mail prices start at $10.45 per package and $11.90 for flat-rate Priority Mail envelope – they are expected to increase 6.6%Priority Mail Express packages start at $32.50 and flat rate envelopes start at $33.40 – they are expected to increase by 5.1%USPS Ground Advantage starts at $7.20 and is expected to increase by 7.8%Parcel Select is expected to increase by 6%How much is a postage stamp – First-Class Mail?

The standard First-Class Mail letter rate for USPS or cost of a postage stamp is $0.78 for the first ounce and goes up $0.29 per additional ounce. This price has been in effect since July 2025 and is not expected to rise in January 2026. The next possible price change is anticipated in mid-2026.