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

> Closed. Last odds frozen 14 h ago — final outcome on the venue.

URL: https://simplefunctions.dev/odds/us-officially-declare-war-iran
Updated: 2026-06-19T01:20:20.801Z
Category: geopolitics · Topic: iran
Status: historical
Closes: 2026-12-31

## Headline

- Probability: 6% (liquidity-weighted across 1 contract)
- Venue: Polymarket (1 contract)
- 24h volume: $1K

## Bound contracts (1)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| December 31 | 6¢ | −1pp | $1K | polymarket | /markets/will-the-us-officially-declare-war-on-iran-by-dece-polymarket-0x3285179b99df57b0390e480f8e69d340e5fa38496b263225df90ef389e2958f4 |

## 30-day trajectory

| Day | Aggregate |
|---|---|
| 2026-06-01 | 7 |
| 2026-06-04 | 6 |

_2 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## Analysis

This probability represents the likelihood that the U.S. government formally issues a declaration of war against Iran by an unspecified end date. At 8%, the market reflects skepticism about such an extreme escalation, despite current tensions. The level is driven primarily by two competing dynamics: regional instability and ongoing diplomatic channels remain active, while military posturing and rhetoric from various parties create downside risk. The key catalyst for repricing would be a major military incident—such as an Iranian attack on U.S. forces or allies, or verified credible intelligence of imminent Iranian action—that creates pressure for immediate congressional action. Without such a triggering event, inertia favors continued containment strategies over formal war declarations, which require explicit congressional authorization and represent a significant political commitment.

### Key factors

- Current U.S. military presence in the Middle East and stated deterrence posture against Iranian regional activities
- Status of ongoing diplomatic negotiations or sanctions regimes—whether escalating or stabilizing
- Iranian military capabilities and recent provocative actions or statements indicating intent to escalate
- Congressional appetite for war authorization given historical reluctance post-2003 Iraq invasion
- Regional proxy activities by Iranian-backed forces and potential for uncontrolled escalation from incidents

## Methodology

Probability is **liquidity-weighted** across all bound Kalshi/Polymarket contracts: Σ(price × volume) ÷ Σ(volume). 30-day trajectory uses the daily mean of intraday 5-min captures. 24h delta = today's mean − yesterday's mean. Movement events are ≥3pp daily moves in the last 7 days.

## How to use this data

- HTML: https://simplefunctions.dev/odds/us-officially-declare-war-iran
- JSON: https://simplefunctions.dev/api/public/odds?slug=us-officially-declare-war-iran
- Topic hub: https://simplefunctions.dev/predictions/iran

## License

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