IAEA visits Isfahan, Fordow, or Natanz nuclear site by 2026?

Platform comparison

Market context

The underlying question is straightforward: will International Atomic Energy Agency inspectors physically enter any of three Iranian nuclear sites—Isfahan, Fordow, or Natanz—before the end of 2026? A YES share pays out if at least one such visit occurs; a NO share pays out if none do. The current crowd assessment sits at 0% probability of YES, implying traders believe no IAEA visit to these facilities will happen within the next two years.

IAEA access to Iranian nuclear sites has been episodic and politically fraught. Between 2016 and 2018, under the Joint Comprehensive Plan of Action (JCPOA), IAEA inspectors conducted routine visits to these facilities. That access largely ceased after the United States withdrew from the agreement in May 2018 and Iran subsequently restricted inspector access. In September 2023, Iran's parliament passed legislation further limiting IAEA monitoring rights. However, diplomatic precedent shows that access can be restored through negotiation: the JCPOA itself represented a breakthrough after years of minimal inspections. The 0% probability reflects the current diplomatic freeze rather than a permanent structural barrier.

Traders should monitor announcements from the IAEA Director General, statements from Iran's Atomic Energy Organisation, and any signals of renewed nuclear negotiations. The International Atomic Energy Agency's quarterly reports to the UN Security Council detail access status and any changes to inspection arrangements. Any thaw in US–Iran relations, revival of nuclear talks, or pressure from the UN Security Council could shift the calculus. Conversely, escalating regional tensions or further Iranian restrictions would reinforce the current assessment.

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 Prediction Market UK. 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.

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%.