Supreme Court Poised to Rule on ‘Election Day’ Mail-In Ballot Case

A major election-law case now before the U.S. Supreme Court could reshape how states count mail ballots in federal elections, with potential consequences for California and more than a dozen other states that currently allow certain ballots to arrive after Election Day.

The case, Watson v. Republican National Committee, centers on a fundamental question: whether federal law allows states to count ballots received after Election Day if those ballots were mailed on or before Election Day.

The justices heard oral arguments in March and are expected to issue a decision before the end of the Court’s current term this month.

At the center of the dispute is a Mississippi law allowing absentee ballots to be counted if they are postmarked by Election Day and received within five business days afterward.

Republican challengers argue that the policy violates federal statutes establishing a single national Election Day for presidential, Senate, and House elections.

Their argument is direct: if Congress created one Election Day, then ballots in federal elections should be received by that day in order to be counted.

Mississippi officials disagree, arguing that states have broad constitutional authority to manage election procedures and that ballots mailed by Election Day should remain valid even if postal delays cause them to arrive later.

The dispute dates back to 2020, when Mississippi enacted House Bill 1521 during the COVID-19 pandemic. The law created a five-day grace period for absentee ballots that were mailed by Election Day but arrived afterward.

In 2024, the Republican National Committee and other plaintiffs challenged the law in federal court.

A federal district court initially upheld Mississippi’s policy. However, the U.S. Court of Appeals for the Fifth Circuit later ruled that federal election law preempts the state’s post-Election Day ballot receipt window.

Mississippi appealed, and the Supreme Court agreed to take up the case last year.

The stakes go far beyond one state.

Roughly 15 states and the District of Columbia currently permit at least some ballots to arrive after Election Day and still be counted, as long as they satisfy postmark requirements.

California is among them. Under California law, mail ballots can be counted if they are postmarked by Election Day and received within the state’s statutory deadline of seven days afterward.

A ruling for the Republican challengers could require states to change their election rules and mandate that ballots in federal elections be received by Election Day.

Supporters of that approach argue it would establish a clearer national standard, reduce confusion, and prevent prolonged ballot-counting periods that leave voters waiting days or even weeks for final results.

Critics argue that such a ruling could invalidate ballots from voters who mailed them on time but were affected by postal delays outside their control.

During oral arguments, several justices focused on the meaning of federal laws setting one national Election Day. Court observers noted that the justices pressed both sides on whether counting ballots received after Election Day is consistent with Congress’s decision to create a uniform federal election date.

The Court has not yet issued its decision, and the final outcome remains uncertain.

Still, the ruling could become one of the most consequential election-law decisions in years.

If the challengers prevail, states with post-Election Day ballot receipt windows may be forced to revise their rules for federal elections. Such a decision could significantly shorten vote-counting timelines and reduce the number of ballots counted after Election Day.

If Mississippi prevails, states would retain flexibility to allow ballots mailed by Election Day to arrive during a limited grace period and still be counted.

With the 2026 midterm elections approaching, election officials, political parties, and voting-rights organizations across the country are watching closely.

For conservatives, the case highlights a core issue in election integrity: Election Day should mean Election Day. Long counting windows, late-arriving ballots, and uneven state rules have fueled public distrust and left too many races unresolved long after voters go to bed.

A clear national standard would not eliminate every election dispute, but it could strengthen confidence by making one principle unmistakable: ballots in federal elections must be handled under rules that are transparent, uniform, and consistent with federal law.

The Supreme Court’s decision, expected before the end of June, could determine whether that principle becomes the rule nationwide.