Will Joao Fonseca win the 2026 Men's US Open?

Fee-adjusted Yes on one venue and No on another for Will Joao Fonseca win the 2026 Men's US Open?. Indigo rings on the prices above mark those asks. Assume equivalent resolution.

Yes onPolymarket↗4.5¢+No onKalshi↗94.4¢=98.9¢combined·+1.1% implied

Always check contract rules before trading.Compare contract rules ↓

Fees

For the cross-venue prices shown above — same venue, same schedule for each outcome.

Trading fees

From each venue's own fee data or published rules (Polymarket: fee schedule on the market; Kalshi: official taker formula). The simple percent is a shorthand—actual dollars still depend on price and size. Hover a venue for full wording.

Polymarket: 3%
Kalshi: 7%

Contract rules

Compare the exchange-specific contract text behind the prices above.

PPolymarket

Description

The 2026 U.S. Open tennis tournament is scheduled for August 23 - September 13, 2026. This market will resolve to the player that wins the 2026 U.S. Open Men’s Singles Tournament. If at any point it becomes impossible for a listed player to win the 2026 U.S. Open Men’s Singles Tournament per the rules of the tournament, the corresponding market will resolve to “No”. If the 2026 U.S. Open Men’s Singles Tournament is cancelled, postponed after October 31, 2026, or there is otherwise no winner declared within that timeframe, this market will resolve to “Other”. The primary resolution source will be official information from the U.S. Open (https://www.usopen.org/index.html); however, a consensus of credible reporting may also be used.

Close date

Sep 13, 2026

KKalshi

View contract↗

Description

If Joao Fonseca wins the 2026 Men's French Open professional tennis tournament, then the market resolves to Yes.

Resolution criteria

The following market refers to the 2026 Men's French Open professional tennis tournament. If the participant forfeits, withdraws from consideration, or takes any official action that removes them from being able to win the 2026 Men's French Open professional tennis tournament, the market will resolve “No” for that participant.

Close date

Jul 8, 2026

Resolution date

Jun 10, 2026