Will the US officially declare war on Iran by December 31, 2026?

Resolution criteria

This market will resolve to "Yes" if the United States formally declares war on Iran through an act of Congress between market creation and the specified date, 11:59 PM ET. Otherwise, this market will resolve to "No." To qualify, Congress must pass a formal declaration of war, consistent with its constitutional authority under Article I, Section 8. Authorizations for the use of military force (AUMFs), executive orders, presidential statements, or military actions do not qualify unless accompanied by a formal declaration of war enacted by Congress and signed into law. The resolution source will be a clear consensus of credible reporting.

About this market: This Polymarket prediction market tracks whether the United States will formally declare war on Iran through congressional action by December 31, 2026. Despite four months of active military operations including strikes that killed Iran's supreme leader, traders price just 6 percent odds of formal declaration, reflecting eighty years of precedent in which America has fought wars without invoking its constitutional war power. The June 2026 ceasefire framework and recent violations add near-term uncertainty, but institutional practice heavily favors continued executive action without congressional authorization. read the full analysis