Will the US officially declare war on Iran by...?

Traders currently price "December 31" at 5% for "Will the US officially declare war on Iran by...?". Over the past 24 hours that probability moved up 0.5 points. Full distribution: December 31 5%, March 31 0%, April 30 0%. The market has traded $7.7M in total volume and resolves Dec 31, 2026. Recent diplomatic progress has sharply reduced trader expectations of a formal U.S. congressional declaration of war on Iran. On June 15, 2026, U.S. and Iranian officials reached a preliminary memorandum of understanding establishing a 60-day ceasefire extension, reopening of the Strait of Hormuz, and renewed talks on Iran’s nuclear program, with formal signing scheduled for June 19 in Switzerland. This framework follows months of U.S. and Israeli strikes beginning February 28, 2026, and Iranian retaliatory actions, yet Congress has issued no authorization for use of military force or declaration. G7 support and asset/sanctions discussions further signal de-escalation momentum. Any breakdown in the upcoming talks or renewed major escalation could still alter probabilities before market resolution dates.

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