Platform comparison
| Platform | YES odds | NO odds | Fee | KYC | Settlement | |
|---|---|---|---|---|---|---|
Polymarket (via Best Prediction Markets) Pick polygram.ink (preferred broker) |
100% | 0% | 0% (USDC on-chain) | No-KYC up to $1,500 | USDC, auto via UMA oracle | Live odds → |
Polymarket (direct) polymarket.com |
100% | 0% | 0% | Geo-blocked in US/UK/EU | USDC, on-chain | Live odds → |
Kalshi kalshi.com |
— | — | Up to 7% per trade | US-only, KYC required | USD | Live odds → |
Betfair Exchange betfair.com |
— | — | 2-5% commission | Full KYC from first trade | GBP / EUR | Live odds → |
Manifold Markets manifold.markets |
— | — | Play-money (mana) | None — play-money | Mana (no cash-out) | Live odds → |
Outcome probabilities
Current market-implied probability for each outcome, from the live order book.
| Outcome | Probability |
|---|---|
| National Bank Open: Marta Kostyuk vs Madison Keys Set 1 Winner | 100% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 1 O/U 8.5 | 100% |
| National Bank Open: Marta Kostyuk vs Madison Keys | 98% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set Handicap +/-1.5 | 92% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 2 Winner | 91% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 2 O/U 10.5 | 51% |
| Completed Match | 50% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 2 O/U 8.5 | 50% |
| National Bank Open: Marta Kostyuk vs Madison Keys Match O/U 21.5 | 50% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 2 O/U 9.5 | 50% |
| National Bank Open: Marta Kostyuk vs Madison Keys Match O/U 22.5 | 50% |
| National Bank Open: Marta Kostyuk vs Madison Keys Match O/U 23.5 | 50% |
| National Bank Open: Marta Kostyuk vs Madison Keys Total Sets: O/U 2.5 | 10% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set Handicap +/-1.5 | 5% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 1 O/U 9.5 | 0% |
| National Bank Open: Marta Kostyuk vs Madison Keys Set 1 O/U 10.5 | 0% |
Market context
Market consensus: 100% chance of national bank open: marta kostyuk vs madison keys. Prediction markets aggregate real capital to produce this probability signal. This market refers to the tennis match between Marta Kostyuk and Madison Keys in the National Bank Open, originally scheduled for August 5, 2026 at 11:00AM ET. This market will re…
Methodology
This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Best Prediction Markets, which mirrors the Polymarket order book directly.
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.
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 Best Prediction Markets. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.
- 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.
- What does Polymarket cost to trade?
- Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.
- 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 Best Prediction Markets trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.
Trade National Bank Open: Marta Kostyuk vs Madison Keys on Best Prediction Markets
Live order book, 0% fees, USDC settlement in seconds.
Open live market →