In a move that could reshape how elections are conducted across the country, the U.S. Supreme Court agreed Monday to hear a case that will determine whether states can legally count mail-in ballots received after Election Day — a practice currently allowed in 17 states and the District of Columbia.
The high court’s decision to take up the case follows a legal battle out of Mississippi, where the Republican National Committee and the state’s GOP challenged a longstanding rule that permitted mail-in ballots to be counted if they were postmarked by Election Day but arrived up to five days later. The Fifth Circuit Court of Appeals ruled in favor of the challengers, holding that federal law, which designates “the Tuesday next after the first Monday in November” as Election Day, preempts any state law that extends ballot counting beyond that single day.
At the center of the debate is a deceptively technical but critical legal question: What counts as “Election Day”? And more specifically, Can a state continue counting legally cast ballots after that day has passed?
Mississippi Secretary of State Michael Watson, a Republican, asked the Supreme Court to reverse the lower court’s ruling, warning that it “defies statutory text, conflicts with this Court’s precedent, and — if left to stand — will have destabilizing nationwide ramifications.” According to Watson, so long as voters cast their ballots by Election Day — whether in person or by mail — those votes should count, even if received a few days later.
The case has attracted support from 19 Democratic-led states and Washington, D.C., all of which permit some form of post-Election Day ballot receipt. They argue that the federal statute sets the date of the election but does not explicitly prohibit counting votes received later, as long as those votes were cast on or before the legal deadline.
The Republican National Committee, by contrast, urged the Supreme Court not to hear the case, claiming the Fifth Circuit’s ruling was sound and well within constitutional boundaries. In its brief, the RNC wrote, “A post-election receipt deadline for mail ballots thus extends ‘the election’ beyond the ‘day’ set by Congress.” The brief warned that such policies create weeks-long periods of electoral uncertainty and undermine voter confidence in the integrity of results.
The stakes are high. If the Court upholds the Fifth Circuit’s decision, many states will be forced to amend their election procedures — potentially throwing preexisting mail-in voting laws into disarray ahead of the 2026 midterms. Conversely, a ruling in Mississippi’s favor could affirm the rights of states to tailor ballot receipt policies to meet logistical and voter-access needs, particularly in rural or mail-dependent regions.
President Donald Trump has already drawn a hard line on the issue. Earlier this year, he issued an executive order directing the Department of Justice to take action against states that count ballots received after Election Day. He has long argued — without evidence — that mail-in voting facilitates fraud, and has made eliminating post-Election Day counting a central piece of his broader electoral reform platform.
The Court’s decision to hear the case all but ensures a definitive ruling on the tension between federal election timelines and state-level flexibility. It could also determine how long Americans will wait for election results — and whether a vote cast on time, but received late, will ever be counted again.
