Which countries will send warships through the Strait of Hormuz by August 31?

Platform comparison

Market context

The immediate change is that, over the past couple of days, Iran has again warned US warships over route changes in the Strait of Hormuz, underlining that any naval transit there remains politically sensitive and operationally visible. Reuters reported on 25 June that UN-led escort activity through Hormuz was halted after a vessel came under threat, which shows how quickly maritime security arrangements can be tightened or paused when the waterway is under pressure.[17][11]

That keeps the current 8% crowd price anchored to the fact that *named-country* warship transits are still uncommon and usually require either a deliberate diplomatic decision or a crisis response. Earlier this year, US ships transited the strait, while the UK said in May it was deploying drones, fighter aircraft and a Royal Navy warship as part of an international defensive mission; separately, Trump publicly urged countries including China, France, Japan, South Korea and Britain to send ships, but reporting at the time said there were no immediate commitments from those states.[15][1][2][3]

For traders, the main catalysts are formal defence announcements, coalition escort schedules, and any public confirmation of naval departures from participating governments or their militaries. Watch for a repeat of the sort of joint-security messaging seen in spring, because that is the clearest path to a qualifying transit; absent that, coverage is more likely to focus on warnings, patrol posture, and commercial shipping disruption rather than a fresh warship passage by a new country.[1][12][14]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

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