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MARKET RESOLVEDKalshi / Polymarket / ProphetX

Elvina Kalieva Wins: Sofia Costoulas vs. Elvina Kalieva

WTA·Resolved 2026-08-26

This market resolved on 2026-08-26. Elvina Kalieva was the officially declared outcome. Prior to resolution, the market peaked at 99%.

About This Market

Sofia Costoulas vs.

Sofia Costoulas vs. Elvina Kalieva — WTA Tennis match held on 2026-08-26. Review the historical prediction market odds from Kalshi, Polymarket, and more on Prediction Hunt.

Price History

Multi-Platform Probabilities

Learn more:How to Read Prediction Market Prices Compare Fees Before You Trade New to Polymarket?

Market RulebooksOfficial settlement criteria and edge cases

Official settlement criteria, resolution sources, and edge cases across Kalshi and Polymarket and ProphetX.

Rules for Candidate:

Kalshi

Primary Rule

If Elvina Kalieva wins the Kalieva vs Costoulas professional tennis match in the 2026 US Open Women Singles Qualification Round 2 after a ball has been played, then the market resolves to Yes.

Edge Cases

The following market refers to the Kalieva vs Costoulas professional tennis match in the 2026 US Open Women Singles Qualification Round 2 after a ball has been played. If the match does not occur (signaled by a ball being played) due to a player injury, walkover, forfeiture, or any other cancellation (all before the match starts), the market will resolve to a fair price in accordance with the rules. If this match is postponed or delayed, the market will remain open and close after the rescheduled match has finished (within two weeks). Kalshi is not affiliated, associated, authorized, endorsed by, or in any way officially connected with the Governing League. All trademarks, logos, and brand names are the property of their respective owners.

Resolution Oracles

Kalshi Rules

Polymarket

Primary Rule

This market refers to the tennis match between Elvina Kalieva and Sofia Costoulas in the US Open, Qualification WTA, originally scheduled for August 26, 2026 at 5:00PM ET. This market will resolve to 'Elvina Kalieva' if Elvina Kalieva advances against Sofia Costoulas. This market will resolve to 'Sofia Costoulas' if Sofia Costoulas advances against Elvina Kalieva. If the match is canceled (not played at all), ends in a tie, or a winner has not been determined by September 9, 2026, 11:59 PM ET (14 days after the scheduled start), this market will resolve to 50-50. If the match begins but is not completed, and one player advances due to the opponent's retirement, default, or disqualification, this market will resolve to the player who advances. If the match ends in a walkover (player withdraws before the start and the other advances automatically), this market will resolve to 50-50. The primary resolution source will be official information from the WTA Tour. A consensus of credible reporting may also be used.

Resolution Oracles

UMA Optimistic OracleConsensus of Sources

ProphetX

Primary Rule

Sports moneyline - resolves based on official game outcome per ProphetX Prediction Rules

Resolution Oracles

ProphetX Rules

Frequently Asked Questions

What does the Sofia Costoulas vs. Elvina Kalieva prediction market track?

The outcomes listed above show how traders are pricing this question. Compare outcome prices from Kalshi, Polymarket, ProphetX in one place. Each price reflects the market’s implied probability, not a guaranteed result. This event is archived; prices shown are historical.

What were the last available Sofia Costoulas vs. Elvina Kalieva odds?

The last available prices are Elvina Kalieva: 99.0¢ on Kalshi, 99.9¢ on Polymarket, 89.2¢ on ProphetX; Sofia Costoulas: 1.0¢ on Kalshi, 91.0¢ on Polymarket, 12.7¢ on ProphetX. Prices are quoted in cents per $1 share. Check the venue for executable prices and available liquidity. The last available price is not necessarily the final settlement price.

Why do Sofia Costoulas vs. Elvina Kalieva odds vary across prediction markets?

The largest price difference shown across venues is 90.0 percentage points. Venues have different traders, liquidity and fees, so their prices can differ. A price gap alone does not establish an executable arbitrage opportunity; compare settlement rules and the actual buy and sell prices.

How do Sofia Costoulas vs. Elvina Kalieva prediction market payouts work?

For example, Elvina Kalieva at 96.0¢ implies about a 96.0% chance. For a standard $1 contract, a share pays $1 if its outcome settles as correct and $0 if it settles as incorrect. A winning share bought at 40¢ earns 60¢ before fees. Check each venue’s settlement rules, fees and eligibility before trading. Historical prices alone do not identify the winning outcome.

Candidate
Elvina KalievaWINNER	99%	100%	89%
Sofia Costoulas	1%	91%	13%

Elvina Kalieva Wins: Sofia Costoulas vs. Elvina Kalieva

About This Market

Price History

Elvina Kalieva Wins: Sofia Costoulas vs. Elvina Kalieva

About This Market

Price History

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Final Closing Odds

Resolution Oracles

Frequently Asked Questions

Elvina Kalieva Wins: Sofia Costoulas vs. Elvina Kalieva

About This Market

Price History

Elvina Kalieva Wins: Sofia Costoulas vs. Elvina Kalieva

About This Market

Price History

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Dallas Stars vs. Nashville Predators

TheChampionGG vs. SINQU Rehti

Jack Bruce-Smith vs. Lachlan Vickery

Colgate Raiders vs. Harvard Crimson

Dmitry Popko vs. David Tixhon

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Dallas Stars vs. Nashville Predators

TheChampionGG vs. SINQU Rehti

Jack Bruce-Smith vs. Lachlan Vickery

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Final Closing Odds

Resolution Oracles

Market Rulebook: Sofia Costoulas vs. Elvina Kalieva

Frequently Asked Questions