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

Platform comparison

Market context

Polymarket’s contract on warship transits through the Strait of Hormuz is priced at **8% YES** today, which implies traders see only a limited chance that any listed government will have a qualifying naval passage recorded before the 31 August deadline. Because settlement is in **USDC** on **Polygon** via conditional tokens, the market is essentially asking whether a verifiable military or government-confirmed transit will happen, not whether rhetoric around Hormuz stays elevated.

That low price sits against a year of high but uneven precedent. The Strait has already seen military and quasi-military activity linked to the 2026 crisis, including the UK’s announced deployment of drones, fighter aircraft and a Royal Navy warship for a defensive mission, plus reported joint drills involving Russia, Iran and China in the waterway.[1][2] Earlier Polymarket versions of the same theme also showed that headline pressure did not necessarily translate into broad participation; one prior Hormuz warship market resolved **No** despite US and UK naval activity in the region, which is a useful reminder that this contract only pays on a defined transit, not on escort missions or nearby deployments.[17]

For traders, the key catalysts are official naval schedules, coalition announcements, and any fresh reporting of a ship actually crossing the strait under a national flag. Reuters reported in March that Donald Trump said “many countries” would send warships to keep the passage open, but no commitments were confirmed then.[5][8] Since August has brought renewed warnings around routing in the strait, any change in Iranian posture, allied escort plans, or a named deployment from the UK, France, China, Japan, South Korea or others would be the kind of event that can move this contract quickly.[11][20]

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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

UK Frequently Asked Questions

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Polymarket Alternative UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.