By Fredreka Schouten

(CNN) — If you rely on postmarks when casting your ballot, filing your taxes or paying bills, a new US Postal Service rule makes it clear that you should plan ahead.

Postmarks – which include a date stamp from the USPS – can offer proof that a piece of mail, such as a ballot, was turned in by a legal deadline.

But the new rule, which went into effect last week, clarifies that a postmark does not “necessarily” reflect the date the USPS “first accepted possession” of the piece of mail.

That’s because most postmarks are applied at regional mail-processing hubs, and the USPS has undertaken a major overhaul that includes eliminating multiple daily trips between post office locations and those facilities.

As a result, people in some parts of the country – particularly in rural areas far away from regional processing hubs – can experience delays between dropping off their mail and having it postmarked.

The Postal Service said it has not changed its postmarking practices but issued the new rule to make clear to the public what a postmark denotes.

Voting by mail grew more widespread during the pandemic and made up about 30% of the turnout in the 2024 election, according to federal data. That’s down from a high of about 43% in 2020. Currently, 14 states – including the presidential battleground of Nevada – accept regular mailed ballots received after Election Day, provided they are postmarked on or before that day, according to the National Conference of State Legislatures.

The changes at the Postal Service – and the potential impact on mail ballots – come against the backdrop of President Donald Trump’s drive to sharply curtail mail-in voting. He has railed against the practice as rife with fraud, despite no evidence of widespread wrongdoing.

An executive order the president signed in March sought to mandate changes to mail-in balloting and other election practices, but has been blocked, in part, by the courts. In 2025, four states – Kansas, North Dakota, Ohio and Utah – eliminated their grace periods for counting mailed ballots received after Election Day.

The ultimate fate of late-arriving ballots likely rests with the US Supreme Court. The justices will decide this term whether states may count mail-in ballots that arrive after Election Day, in a Republican-led case. It originated with a challenge to a Mississippi law enacted during the pandemic that allows ballots to be received up to five days after the election.

This year, election officials have sought to alert voters to their concerns about late-arriving mail ballots.

California Attorney General Rob Bonta cited the USPS changes to exhort voters who live more than 50 miles away from USPS mail-processing hubs to cast their ballots early ahead of a November special election on redistricting. Similarly, in Oregon – the first state to adopt a universal vote-by-mail system – Secretary of State Tobias Read warned voters that ballots that were mailed in after October 30 might not receive a postmark in time for the November 4 election.

Tess Seger, a spokesperson for Read, said Oregon officials “plan to continue to raise awareness about this issue” ahead of next year’s elections.

The Postal Service has long recommended that voters mail their completed ballots at least a week before they must be received by their local election offices.

In a statement sent to CNN this week, the Postal Service said that any customer who wants to ensure that a piece of mail receives a postmark can take it to a Post Office retail counter and request a manual postmark. Customers also have the option of using certified or registered mail, for a fee.

The-CNN-Wire
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