National Bank Open: Maria Sakkari vs Coco Gauff

Platform comparison

Market context

Polymarket is currently pricing the contract at **0% YES**, so the market is effectively saying there is no live chance of a Maria Sakkari advance being reflected in the current price. On Polymarket, this contract is bought and sold in **USDC** on **Polygon**, and the outcome is represented through conditional tokens that settle against the match result, or against the market’s fallback rule if the contest is not completed as specified.

The historical frame is not one-sided enough to make the price obvious from name recognition alone. Gauff and Sakkari have met repeatedly, with head-to-head records published by different trackers showing the rivalry is close overall, while recent match data in the National Bank Open records point to Gauff having stronger service and return numbers in their latest completed meeting[3][4][5][17]. That mix matters for traders because prediction markets can stay pinned near zero when a player is clearly favoured, but tennis volatility is still meaningful: retirements, walkovers, and scheduling changes can flip the settlement path even when one side is heavily backed.

Traders should watch the tournament’s order of play, any official withdrawal or injury update, and whether the match is actually staged within the settlement window rather than merely listed on the draw. The market rules matter as much as the scoreline: if the match is not played, ends level, or is pushed beyond seven days without a winner, it resolves 50-50; if play begins but is unfinished, the advancing player matters for settlement. Live listings show the fixture on 7 August 2026, but the latest status from score and tournament pages indicates traders should verify whether it has been completed or formally advanced before treating the 0% quote as final[1][2][4].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track National Bank Open: Maria Sakkari vs Coco Gauff 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

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.

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 Alternative UK. 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%.