Sion: Sandro Kopp vs Benjamin Hassan

Platform comparison

Market context

Sandro Kopp and Benjamin Hassan are scheduled to meet in Sion on 19 August 2026, with the market currently pricing Kopp at zero probability of advancing. The 0% implied probability reflects either extreme confidence in Hassan or a severe liquidity/information gap, as professional tennis matches between ranked or semi-ranked players rarely settle with such certainty before play.

Comparable ATP Challenger and ITF matches involving lesser-known players have occasionally shown wildly skewed odds when one competitor carries recent form advantages, injury concerns affecting the favourite, or when Hassan holds a significant head-to-head record. However, a complete absence of backing for Kopp suggests either Hassan is substantially higher-ranked, Kopp is carrying a known injury, or the market has received late information about withdrawal risk. Without recent match data between these players, the 0% reading warrants scrutiny—consensus this extreme often masks thin liquidity rather than genuine certainty.

Traders should monitor official Sion tournament draws and ATP/ITF rankings updates through early August, as late withdrawals or seeding changes can shift perceived matchup quality. Any announcement regarding Hassan's recent form, court surface preference, or Kopp's fitness status could materially alter the odds. The settlement window extends to 26 August, providing a week's buffer beyond the scheduled date; delays or walkovers would trigger the 50-50 resolution clause, creating tail-risk exposure for those holding extreme positions.

Methodology

We track Sion: Sandro Kopp vs Benjamin Hassan 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

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

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.

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%.