Warsaw: Teodora Kostovic vs Martyna Kubka

Platform comparison

Market context

Teodora Kostović and Martyna Kubka are playing a Warsaw women’s match on outdoor hard courts, with Kostović ranked WTA 146 and Kubka WTA 187 at the time of the listing.[1][3] For a market showing 0% YES on Polymarket, that price implies almost no chance the contract resolves to Kostović advancing, but on exchanges such as Betfair or Smarkets the same view would normally be expressed as a decimal price rather than an implied probability, with fees and KYC access varying by venue.

The main historical reference point is their head-to-head: Kubka beat Kostović 6-3, 6-1 at Leimen in February 2025, giving Kubka the only recorded win in the pair’s meetings.[2][13] That is the most relevant comparable case for reading the current line, although one past result on a different surface is thin evidence on its own. Independent match pages also show some disagreement on surface and timing, with listings variously describing the event as hard-court or clay and giving slightly different start times, which is a reminder that live settlement depends on the official competition record rather than a single data feed.[1][8][9][14]

Traders should watch the official order of play and any late schedule changes, because the market resolves on advancement and can revert to 50-50 if the match is not played or is delayed beyond seven days. Sofascore listed the match for 3 August 2026 at 13:10 UTC, while other feeds showed later local times, so any postponement, retirement or walkover announcement would be more important than pre-match form.[1][3][4] On different platforms, that same event may be quoted as a percentage, a decimal price, or an exchange back/lay market, and access can differ because Kalshi-style US access is not the same as the broader reach offered by offshore exchange books such as Betfair.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Warsaw: Teodora Kostovic vs Martyna Kubka specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Robinhood Prediction Markets, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Robinhood Prediction Markets offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.