What’s the betting on closure by March 31? According to Polymarket, it’s 82% right now…

Source: Polymarket, 5 March 2026, 9pm CT.

The terms of the contract are:

Per the rules, this market requires Iran to halt or severely restrict international maritime traffic through the Strait of Hormuz. “Severely restrict” will be defined as a 80% or greater decrease in the 7 day moving average of commercial vessel transits (both cargo and tanker ships) on a given date when compared to the seven-day moving average 30 days prior, as reported by the IMF’s PortWatch service (see: https://portwatch.imf.org/pages/cb5856222a5b4105adc6ee7e880a1730), with the decrease being directly caused by actions taken by the Iranian regime. A consensus of credible reporting or government sources confirming that Iran has halted maritime traffic through the Strait of Hormuz will also qualify.

I don’t have up-to-date data, but the IMF’s Portwatch system provides data through March 1:

Source: IMF PortWatch, accessed 5 March 2026.

20% of oil exports go through the Strait; complete closure results in a spike in Brent to $108, according to Bloomberg Economics.

Here’s the current picture (red arrows are tankers):

Source: MarineTraffic.com, accessed 5 March 2026, 10pm CT.