National Bank Open: Sloane Stephens vs Belinda Bencic

Platform comparison

Market context

Polymarket is pricing the Sloane Stephens–Belinda Bencic contract at **0% YES**, which means the market is effectively assigning no value to a Stephens advance and is treating a Bencic win, or a non-standard settlement outcome, as the live reference on the contract’s USDC/Polygon conditional-token rails. The underlying event is a second-round women’s singles match at the National Bank Open in Toronto, listed for 5 August with hard-court conditions at Sobeys Stadium.[1][3][4]

That near-zero price sits well below the pre-match tennis view. Tennis.com’s model showed Bencic with an **84% projected winner** probability, while Stephens entered as the clear outsider at ranking level, with Bencic listed around world No. 14 and Stephens far lower in the live tournament data.[1][2] Comparable pricing logic in tennis markets usually tracks rankings, surface fit and draw strength rather than headline name value; on that basis, a 0% YES quote implies traders have already discounted Stephens heavily, even before considering the market’s fallback rules if the match is not completed.[1][5]

The main catalysts are practical rather than narrative: whether the match begins on schedule, whether it is completed, and whether any injury, retirement or weather disruption pushes settlement into the market’s special 50-50 case if no winner is determined within seven days of the original date. Tournament listings and live score pages show the fixture as active on 5 August, and recent coverage from The Athletic on 4 August placed Stephens v Bencic in the day’s Round of 64/second-round schedule, confirming that the key trading variable is execution, not discovery of the fixture itself.[3][10][15]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews National Bank Open: Sloane Stephens vs Belinda Bencic across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

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 PolyGram. 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%.