States challenging Trump’s mail voting rule must mail more than 51 million ballots by late October

An election worker processes mail-in ballots during California's primary election on June 2, 2026. (Photo by Patrick T. Fallon / AFP via Getty Images)

More than 51 million mail ballots will be sent to voters in the coming weeks just from the District of Columbia and the two dozen states that are challenging the Trump administration’s 11th-hour attack on mail voting.

U.S. District Court Judge Indira Talwani leaned on those numbers to help justify her Friday order blocking the U.S. Postal Service from implementing a new rule imposing new envelope requirements on states just days or weeks before deadlines to mail ballots to voters.

In California alone, election officials are preparing to send out more than 23 million mail ballots. North Carolina has already begun mailing ballots to 260,000 voters. Later this month, mail ballots are set to go out in even more states, including 5.1 million in Washington, which votes entirely by mail; 4 million in Colorado; and 3.2 million in Arizona. States have firm deadlines to complete mailing out ballots, with most due to finish by late October.

Talwani’s order, released just 60 days before the midterms, temporarily halts a USPS rule designed to carry out President Donald Trump’s sweeping executive order to limit mail voting. Democratic attorneys general from 24 states and the District of Columbia are challenging the rule, warning it would wreak havoc on mail voting. 

In her order, Talwani concluded it was “practically inevitable” that, if left to stand, the rule would prevent voters from casting ballots this year.

Traditionally, USPS does not play a role in deciding whether voters receive mail ballots. However, under the new rule, states would be required to give the postal agency a list of all voters who requested a mail ballot for the upcoming election. USPS would then use the lists to determine which ballots will be sent to voters.

The U.S. Department of Justice is asking the U.S. Supreme Court for an immediate stay lifting the block on the USPS rule. It has also asked the 1st Circuit Court of Appeals to stay the ruling. 

The Justice Department argues that the Postal Service is well within its power to regulate ballot envelope design. Despite the tight timeline to get the envelope designs approved by the Postal Service and submit a list of approved mail voters to a federal portal that has not yet gone live for states to use, the Justice Department insists the rule’s requirements are minor and do not amount to a federal takeover of the election process. 

In contrast, the states have argued that they lack the time and resources to complete the Postal Service review with deadlines rapidly approaching to mail ballots to voters. North Carolina voluntarily sought Postal Service approval for its envelopes before it began mailing its ballots on Friday.