National Bank Open: Elise Mertens vs Anna Bondar

Platform comparison

Market context

The National Bank Open second-round meeting between **Elise Mertens and Anna Bondar** is priced at a **100% YES** crowd view, yet the more grounded pre-match read still has Mertens as the clear favourite rather than an automatic winner. The pair’s only listed head-to-head was a straight-sets Mertens win in Toronto in 2022, and comparison models again lean her way, with Tennis.com projecting Mertens at 72% and String Tension putting her at 80.4%.[1][5][15] That makes the market’s current certainty look stretched: the consensus is firmly on Mertens, but the value case is on the underdog side if this trades off matchup history and ranking gap alone, because Bondar’s live chance is unlikely to be close to zero.

From a handicapper’s angle, the key historical frame is that this is not a clash between strangers, but a rematch on hard court where Mertens has already handled Bondar comfortably.[1][2] The wider 2026 numbers in the available comparison data also favour Mertens on the major hard-court indicators, including a stronger season record and higher service efficiency, which supports her favourite status.[5] For traders, that means the main contrarian angle is not “Bondar is the better player”, but that a 100% probability leaves no room for usual tournament variance, especially in best-of-three tennis where one slow start, medical issue or momentum swing can matter more than the baseline edge.

The near-term catalyst is the actual match status in Toronto: Tennis.com lists the round-two tie with Mertens projected at 72%, while the tournament and live-score feeds show the fixture as scheduled for 5–6 August 2026 depending on local listing, so any delay, retirement or rescheduling risk becomes the real market variable.[13][14][15] The settlement rules also matter: if it is not played, ends level, or is pushed beyond seven days without a winner, the market goes 50-50 rather than either player advancing, so a trader should watch official order-of-play updates and live match completion rather than assume a clean result.[15]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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 Who Will Win. 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.

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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%.