The U.S. Supreme Court on Nov. 10 agreed to decide whether federal election-day statutes bar states from counting mail ballots received after Election Day if they were postmarked by that day, a dispute from Mississippi that could affect rules in more than a dozen states ahead of the 2026 midterms.
On Monday, Nov. 10, the Supreme Court granted review in Watson v. Republican National Committee, a case asking whether federal election-day laws preempt state provisions that allow mail ballots cast by Election Day to be received and counted afterward. The Court’s docket notes the petition was granted on Nov. 10. Arguments are expected in late winter or early spring, with a decision likely by June 2026. (supremecourt.gov)
The dispute arose after the Republican National Committee, the Mississippi Republican Party and others challenged Mississippi’s law permitting timely postmarked mail ballots to be counted if received within five business days of Election Day. A 5th U.S. Circuit Court of Appeals panel ruled that federal statutes require ballots to be received by Election Day, invalidating the state’s five-day window and reversing a district court ruling that had upheld it. The challenge was consolidated with a case brought by the Libertarian Party of Mississippi. (mississippitoday.org)
Mississippi Secretary of State Michael Watson petitioned the Supreme Court, arguing that the 5th Circuit’s decision “defies statutory text, conflicts with this Court’s precedent, and—if left to stand—will have destabilizing nationwide ramifications.” His filing emphasizes that ballots cast by Election Day may be counted if received shortly after. (supremecourt.gov)
Nineteen states and the District of Columbia filed an amicus brief supporting Mississippi and urging the Court to take the case, warning that the 5th Circuit’s approach threatens similar ballot-receipt rules elsewhere. Their brief was filed “in support of petitioner.” (supremecourt.gov)
By contrast, the RNC urged the justices to deny review and defended the 5th Circuit’s reading of federal law. In its brief, the committee wrote: “A post-election receipt deadline for mail ballots thus extends ‘the election’ beyond the ‘day’ set by Congress…. In no sense is the ‘election’ over when ballots are still coming in,” and argued that such policies can prolong tabulations for weeks. (supremecourt.gov)
How many jurisdictions could be affected varies by methodology and recent legislative changes. The Associated Press, citing the National Conference of State Legislatures (NCSL), reports that 16 states plus the District of Columbia accept mailed ballots received after Election Day if postmarked on or before that date; NCSL’s Aug. 1, 2025 update likewise lists 16 states, though earlier tallies placed the number at 17 before some states tightened their deadlines. (apnews.com)
Former President Donald Trump has long criticized mail voting and, on March 25, 2025, issued Executive Order 14248 directing the Justice Department to take action against states that count mail ballots received after Election Day in federal races. Portions of the order have been challenged and preliminarily blocked in court. (whitehouse.gov)
