Will the U.S. invade Iran before 2027?

Platform comparison

Market context

Polymarket is pricing this contract at **18% YES**, with settlement in USDC on Polygon through conditional tokens if the U.S. commences a military offensive intended to establish control over any part of Iran before 31 December 2026. The market is not asking whether the U.S. strikes Iran at all, but whether operations cross the line into an invasion-style offensive aimed at control, which is a narrower and more specific threshold.

The main historical lens is that U.S.-Iran escalation has already moved well beyond rhetoric in 2026. U.S. and Israeli forces launched Operation Epic Fury on 28 February, with CENTCOM saying the mission was focused on destroying Iranian offensive missiles, missile production, naval assets, and other security infrastructure[3][6][13]. Reuters reported in March that Defence Secretary Pete Hegseth said U.S. objectives had not changed, while noting that the Pentagon was considering additional troops and a funding request above $200 billion[11]. That keeps the probability above a pure tail-risk level, but the current price still implies traders see a full-scale attempt to seize and hold territory as materially less likely than continued strikes, deterrence, or coercive pressure.

For the next leg, traders should watch for White House or Pentagon language that shifts from strike objectives to occupation or control, because that is what would matter for resolution. CNN reported on 3 August that the military had been preparing options for renewed strikes on Iranian nuclear sites, while saying the broader campaign had not yet forced Tehran back to negotiations[8]. Any formal troop deployment orders, an expanded mission statement, or evidence of logistics for ground operations would be the clearest catalysts; by contrast, air campaigns, maritime interdiction, or limited retaliatory strikes would not obviously satisfy this market’s wording.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Will the U.S. invade Iran before 2027? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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 PolyGram. 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%.