US-Iran nuclear deal by May 31?

Platform comparison

Market context

Negotiations between Washington and Tehran over Iran's nuclear programme remain stalled as of early 2025, with no formal bilateral talks scheduled and both sides maintaining hardened positions on preconditions. A new agreement would require mutual recognition of previous accords (notably the 2015 JCPOA, abandoned by the US in 2018) or a wholly separate framework addressing uranium enrichment, weapons-grade material stockpiles, and international inspections. The 16-month window to May 2026 represents a compressed timeline for diplomacy that historically requires months of back-channel negotiation before public announcement.

The 22% implied probability reflects the structural difficulty of near-term breakthrough. Previous nuclear agreements—the JCPOA itself, the 1994 Agreed Framework with North Korea, and the 2003 Libya deal—each required 18–36 months of sustained negotiation before signing. Current US–Iran relations lack even the preliminary diplomatic infrastructure those talks possessed; no joint commission is meeting, no special envoys are actively shuttling, and domestic political constraints in both capitals remain acute. The incoming US administration's stated scepticism toward the JCPOA and Iran's continued uranium enrichment expansion both work against rapid accord.

Traders monitoring this market should track announcements from the UN Security Council, International Atomic Energy Agency inspection reports, and any statements from European intermediaries (particularly France, Germany, or the EU foreign service) signalling renewed dialogue. A conditional order structure—triggering on news of resumed talks rather than agreement itself—would help manage tail risk, since the probability of announcement before May 2026 likely exceeds the probability of full settlement. Watch for shifts in Iranian domestic politics following elections or sanctions relief discussions as potential catalysts for position changes.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). The odds column is filled only where we have clean data — that avoids the made-up numbers that get a network demoted when search engines cross-check against the source venue.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Bot UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket Bot UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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 it cost to trade on Polymarket Bot UK?

Zero. Polymarket Bot UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.