National Bank Open: Sloane Stephens vs Belinda Bencic

Platform comparison

Market context

Sloane Stephens’s match with Belinda Bencic at the National Bank Open is trading against a market that currently shows **0% YES**, but the wider tennis market framing points the other way: bookmakers and match-preview outlets make Bencic a clear favourite. One recent price set from an Australian sportsbook quoted Stephens at $6.00 and Bencic at $1.12, which implies roughly an 89% pre-margin chance for Bencic, a stark contrast with the crowd-implied zero on the contract.[17] Tennis.com also lists the contest as Stephens v Bencic in Toronto, with Bencic ranked 14 and Stephens 307, reinforcing the gap in baseline strength.[11]

The historical comparison is mixed but still useful for reading a low-probability contract. Stephens leads the head-to-head 2-0, including a straight-sets win in Guadalajara in 2022, and has not dropped a set to Bencic in either meeting.[1][15] That said, head-to-head is a thin guide here because the pair have met only twice, and Bencic’s current season record and ranking profile are materially stronger than Stephens’s.[19][11] Flashscore’s tournament notes also point to Bencic’s strong record in opening-round play at this event and Stephens’s recent difficulty stringing together back-to-back main-draw wins, which helps explain why analysts lean heavily towards Bencic despite the old matchup edge for Stephens.[7]

For traders, the key catalysts are not just form but whether the scheduled match is actually completed before the settlement window closes. The market description says an unplayed cancellation, tie, or a delay beyond seven days from the original date would settle 50-50, so any weather-related postponement or schedule reshuffle matters as much as the scoreline itself. Live tournament listings indicate the match is on the Toronto order of play for 5–6 August 2026, while WTA and score-tracking pages are the best places to monitor official start-time changes, court assignments, and whether the match has begun or gone unfinished.[9][20][8]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track National Bank Open: Sloane Stephens vs Belinda Bencic 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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

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 Kalshi vs Polymarket. 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.

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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.