Supreme Court to decide if states can count mail ballots received after Election Day — a ruling that could reset 2026 election rules

What the court agreed to decide

The petition asks whether 2 U.S.C. § 7 and 3 U.S.C. § 1 — which set a uniform federal Election Day — bar states from counting otherwise‑valid mail ballots that arrive after polls close, even if postmarked by Election Day. The case is docketed as No. 24‑1260 (Michael Watson, Mississippi Secretary of State v. Republican National Committee, et al.), with briefing this winter and arguments expected early in 2026; a ruling is likely by June. ^[3]

How we got here

The Mississippi rule and the 5th Circuit’s break with past practice

Mississippi law allows counting mail ballots postmarked by Election Day if received within five business days. In October 2024, a 5th Circuit panel held that federal law requires ballots to be both cast and received by Election Day, reversing a district court that had upheld Mississippi’s statute; the full court later denied rehearing. ^[6]

“The stakes are high: ballots cast by — but received after — election day can swing close races and change the course of the country,” Mississippi’s petition argues. ^[7]

By granting review in the Mississippi appeal (Watson v. RNC), the justices will determine whether the 5th Circuit’s interpretation becomes a national rule or remains a regional outlier affecting Mississippi, Texas and Louisiana. ^[8]

Overlap with a broader legal and policy fight

The case arrives as the administration’s March 25 executive order sought to condition federal action on states requiring ballots to be “cast and received” by Election Day — a provision since preliminarily enjoined by a federal judge in Massachusetts. The Court’s ruling will clarify what federal law actually requires, independent of executive directives. ^[9]

What’s at stake for states and voters

States vary widely. According to the National Conference of State Legislatures (NCSL), as of June 2025, 33 states require mail ballots to be received by Election Day, while 17 states — plus D.C. and certain territories — accept ballots that arrive after Election Day if postmarked on time. Military and overseas voters often have additional protections. Those counts could shift as legislatures change laws or courts intervene. ^[11]

How different states handle late-arriving ballots

The competing arguments

Mississippi and allies: Federal preemption and “one day” to receive ballots

Mississippi and allied groups (including the RNC and the Libertarian Party of Mississippi) argue that Congress set a single federal Election Day and that accepting ballots after that date violates federal statutes. They contend divergent state receipt rules create uncertainty and invite litigation after close races. ^[21]

State and local administrators: Postmarks protect timely voters against mail delays

State election officials defending post‑Election Day receipt windows say a postmark is evidence the voter complied by Election Day, and receipt windows simply account for mail transit times. NCSL’s survey shows many jurisdictions accept such ballots (and separate allowances exist for military and overseas voters), indicating long‑standing administrative practice rather than gamesmanship. ^[22]

The executive branch angle: A national receipt mandate enjoined

President Trump’s March 25 executive order directed federal enforcement toward Election‑Day receipt, but a preliminary injunction in June blocked key provisions, with a federal court finding the president likely lacked authority to override state election law. The Supreme Court’s ultimate reading of federal statutes will shape the durability of any such policy going forward. ^[23]

How a ruling could ripple through 2026

Political reactions and next steps

Election‑integrity advocates allied with the RNC praised the 5th Circuit’s reasoning and urged the Supreme Court to keep the ban on counting late‑arriving ballots. Mississippi’s Attorney General Lynn Fitch warned the justices that leaving the 5th Circuit ruling intact without national clarity could have “destabilizing nationwide ramifications,” while administrators emphasize reliance interests and the need to protect timely voters from mail delays. ^[28]

Separately, the Court’s action follows media and court reports that the justices are likely to resolve the case by late June, in time to govern ballot handling in the 2026 midterms — underscoring the practical stakes for campaigns, election offices, and voters. ^[29]

Bottom line

The Supreme Court’s resolution of Watson v. RNC will do more than settle Mississippi’s five‑day rule. It will either reaffirm state flexibility to count timely postmarked ballots that arrive after Election Day or impose a nationwide Election‑Day receipt requirement through statutory interpretation — a choice with direct consequences for election administration, litigation risk, and voter access in 2026 and beyond. 🗳️ ^[30]

References

• Supreme Court docket, Michael Watson v. Republican National Committee, No. 24‑1260 (orders/briefing). ^[31]
• SCOTUSblog, “Justices agree to decide major election law case,” Nov. 10, 2025. ^[32]
• AP, “Supreme Court will decide whether states can count late‑arriving mail ballots,” Nov. 10, 2025. ^[33]
• Reuters, “U.S. Supreme Court to hear Republican bid to limit counting of mail‑in ballots,” Nov. 10, 2025. ^[34]
• NCSL, “Receipt and Postmark Deadlines for Absentee/Mail Ballots,” updated June 16, 2025. ^[35]
• Mississippi code/excerpts and 5th Circuit litigation history (district and appellate summaries). ^[36]
• Executive Order: “Preserving and Protecting the Integrity of American Elections,” Mar. 25, 2025; preliminary injunction June 13, 2025. ^[37]
• AP, “Supreme Court will consider reviving challenge to Illinois mail‑ballot receipt law,” June 2025. ^[38]