Supreme Court upholds Mississippi rule allowing late-arriving absentee ballots

The Supreme Court ruled 5-4 on Monday that federal election-day laws do not block Mississippi from counting absentee ballots that are postmarked by Election Day and arrive within the state’s five-business-day grace period, a decision that preserves similar mail-ballot rules used in many states ahead of the 2026 midterms.

In Michael Watson, Mississippi Secretary of State v. Republican National Committee, the court said federal statutes setting a uniform day for federal elections do not themselves require mailed absentee ballots to be received by that day. Mississippi law allows election officials to count absentee ballots mailed on or before Election Day if they arrive within five business days after the election. As the court put it in its syllabus, “The federal election-day statutes do not prevent Mississippi from counting absentee ballots postmarked by election day but received up to five days thereafter.”

Justice Amy Coney Barrett wrote the majority opinion, joined by Chief Justice John Roberts and Justices Sonia Sotomayor, Elena Kagan and Ketanji Brown Jackson. Justice Samuel Alito dissented, joined by Justices Clarence Thomas and Neil Gorsuch, while Justice Brett Kavanaugh joined parts of the dissent.

The case centered on a Mississippi rule adopted in 2020, when many states were adjusting mail-voting procedures amid the COVID-era expansion of absentee voting and concerns about postal delays. The Republican National Committee and allied plaintiffs challenged the law, arguing that federal election-day statutes mean ballots in federal races must be received by Election Day to count.

The Supreme Court rejected that argument and reversed a ruling from the 5th U.S. Circuit Court of Appeals that had found Mississippi’s law preempted by federal law. A federal district court had upheld the state rule before the appeals court reversed, and the Supreme Court then took the case and reversed the 5th Circuit.

In plain terms, the majority said Congress chose a national day for holding federal elections, but did not set a nationwide ballot-receipt deadline for absentee ballots sent by mail. The opinion also pointed to other federal voting laws, including the legal framework for military and overseas voters, as evidence that Congress has long operated on the assumption that states set receipt deadlines.

That makes the ruling significant well beyond Mississippi. The court described the state as one of roughly 30 states that count at least some absentee ballots mailed by Election Day but received afterward. By rejecting the RNC’s theory, the court removed, at least for now, the immediate threat that federal courts could force states to end those grace-period rules before next year’s midterm elections.

The case grew out of a broader post-2020 Republican legal push against some mail-voting rules, but the ruling itself is narrower than a nationwide endorsement of all late-arriving ballots. It addresses whether the federal election-day statutes at issue preempt Mississippi’s specific rule, not every possible dispute over absentee-ballot deadlines around the country.

The practical stakes can be substantial. Election Assistance Commission data analyzed by the Bipartisan Policy Center found that about 103,408 mail ballots were rejected for lateness in 2024, accounting for about 17.8% of all rejected mail ballots that year. Monday’s decision means Mississippi, and states with similar laws, can continue using postmark-plus-grace-period systems for now without those federal statutes automatically invalidating them.