US spends up to $35B in Iran war, no formal declaration expected

The U.S. has spent between $28 billion and $35 billion in the ongoing Iran war, according to independent reports. The Polymarket contract on a formal war declaration by December 31 now trades at 7% YES, down from 8% yesterday.

Market reaction

The December 31 market sits at 7% YES, while the April 30 market is at 0.5% YES. The spread makes sense given the timelines: 252 days remain on the December contract versus just 7 days for April. Traders are pricing almost no chance of a formal declaration this month but leaving a small window open for the rest of the year.

Trading volume is thin, with $85 in USDC traded over the last 24 hours. The cost to move the December market by 5 points is $3,981, meaning a relatively small order could shift the odds. The largest single move was a 3-point drop in the uranium market at 8:27 PM, showing how reactive these low-liquidity contracts are to new information.

Why it matters

Military spending of $28–35 billion signals real operational commitment, but the market reflects skepticism that spending alone leads to a formal war declaration. Congress would need to authorize war, and there’s no public indication that process has started. A YES share at 7¢ pays $1, but that payout requires concrete steps toward formal authorization, such as a Congressional vote or a formal request from President Trump.

What to watch

Congressional activity is the main signal: bipartisan discussions about war authorization or a formal request from the Trump administration would move this market fast. A major Iranian military escalation or a measurable shift in U.S. public opinion on the conflict could also change the calculus.

API access

Get prediction market intelligence as a structured API feed. Early access waitlist.