Bab el-Mandeb Strait effectively closed by 2026?

Platform comparison

Market context

The Bab el-Mandeb Strait remains a critical maritime chokepoint linking the Red Sea to the Gulf of Aden, handling roughly 10–12% of global seaborne trade. Its closure would trigger massive rerouting, yet the current 0% crowd-implied probability reflects a stark reality: transit volumes have rebounded significantly. In November 2025, transits hit their highest level in nearly two years, with 1,004 recorded, despite being 52% lower than November 2023 figures[2]. Historically, even during the 2024 Yemeni Houthi attacks that forced many carriers to reroute, the strait never saw a sustained seven-day average of arrivals drop to 10 or below; the lowest weekly passings recorded were 235, far exceeding the market’s settlement threshold[9]. This historical resilience frames the current near-zero probability as a rational assessment of baseline traffic stability.

For a power-user evaluating this market programmatically, the primary catalyst to monitor is the geopolitical tension between Yemeni forces and Israeli shipping, which escalated on 5 May 2026 when Yemen declared the strait closed to all Israeli vessels[8]. However, this partial closure has not halted overall traffic, as non-Israeli ships continue transit. Traders must watch for announcements from the IMF PortWatch regarding chokepoint disruption data, specifically the seven-day moving average of transit calls[3]. Recent news indicates carriers are rerouting further as passings drop, yet the volume remains robust enough to keep the settlement condition unmet[10]. A conditional order strategy would involve setting alerts on the PortWatch API for any seven-day average approaching 15, providing an early warning before the critical 10 threshold is breached, though current data suggests this is unlikely before the 2026 settlement window closes.

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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.

FAQ

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 Kalshi Fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.