Traders cool on a US end to Iran's blockade this year

Polymarket's December contract has fallen 18 points since mid-September, to 42%, as nearer dates stay low.

In one line: Washington makes no official announcement ending or suspending its naval blockade of Iran by 31 December, a chance the 42% year-end price still overstates.

Traders on Polymarket now give 42% to Washington announcing an end to its naval blockade of Iran by 31 December. The contract fell 9 points over the seven days to 14 Oct, from 51% on 7 Oct. It stood at 60% at our last digest on 18 Sep and has lost 18 points since.

The fall was not smooth. The price touched a seven-day low of 39% on 10 Oct and has recovered 3 points since, though it lost 1.9 points in the last 24 hours. The other contracts in the event agree that nothing is close. An announcement by 15 Oct trades at 1%, by 31 Oct at 14% and by 30 Nov at 25%.

The rule makes the slide more striking. Trump reinstated the blockade on 13 Jul 2026, and the contract pays if the US government "publicly and officially announces the end, termination, lifting, or suspension" of it. A short pause agreed during talks would count. Traders have marked down even a partial climbdown. Oil points the same way. USO, the oil fund, rose 1.99% on 13 Oct as the contract slipped. The rise fits a reading that Iranian supply stays constrained, though one session proves nothing on its own.

The call: the United States makes no official announcement ending or suspending the blockade by 31 December, and 42% still overstates the chance. A deal struck before 31 October would first have to move the 14% contract. Against the call stand the bounce from 39% and the broad rule: a brief suspension tied to talks in November would pay out and prove that side right. The call is wrong if Washington announces any lift or suspension before 11:59pm ET on 31 December, and the 31 October contract, at 14% today, is the first test.