US-Iran Final Nuclear Deal by…?

Platform comparison

Market context

The event started with a written June agreement and a 60-day negotiation window, so the core question is whether that framework turns into a qualifying final instrument before the deadline. Reuters reported that the memorandum of understanding was scheduled to be officially signed in Switzerland and that it would open a 60-day period to work out the nuclear file, which is the relevant baseline for programmatic monitoring of this market[7][8].

For historical context, this is not the same thing as a completed nuclear deal: earlier 2026 rounds in Geneva and Switzerland were described as progress, guiding principles, or a roadmap, while still leaving major gaps on enrichment, inspections, and sanctions[4][5][3]. That pattern matters for probability reading because markets often overvalue headline diplomatic momentum when the legal endpoint is a signed or formally adopted text rather than a statement of intent, especially after prior talks produced drafts and working groups without immediate finality[1][15].

A trader tracking this through alerts or conditional orders would watch for three practical triggers: publication of the signed text, confirmation that both sides have adopted the same instrument, and any extension that resets the 60-day clock. Reuters and AP both flagged June signing expectations and later described the arrangement as only an initial framework, with the nuclear terms still subject to further negotiation[7][14]. On a live feed, the highest-signal updates are official readouts from Washington, Tehran, or the mediating channel, plus any notice of new technical working groups or inspection arrangements that would indicate the deal is moving from roadmap to enforceable instrument[15][16].

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 Review 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%.