Prediction market Polymarket, where users bet real money on the outcome of world events, shows a 66% probability that US military forces will enter Iran by 30 April 2026, with odds rising sharply over recent weeks.
The market, which has attracted more than $23 million in trading volume, prices the probability of a ground incursion by 31 March at just 24%, suggesting bettors consider an imminent entry unlikely but see the risk building significantly over a slightly longer horizon.
By the end of December 2026, the implied probability rises to 79%, up 30 percentage points from earlier levels, indicating that traders see a US military entry into Iran as more likely than not within the year.
Polymarket resolves the contract as "yes" only if active US military personnel physically and deliberately enter Iranian sovereign territory for operational purposes, excluding cases such as pilots shot down over the country.
The market's rules define Iranian territory using borders as they stood on 28 February 2026.
The sharp upward movement in odds across all three timeframes reflects growing concern among market participants about the trajectory of US-Iran relations following weeks of escalating tensions.