US Open Signs Exclusive Deal With Kalshi

The US Open tournament secured a new exclusive prediction-market partner, Kalshi, at the last minute, according to Front Office Sports. The deal went into effect immediately, though the terms and parameters were not disclosed. The US Open, owned and operated by the U.S. Tennis Association (USTA), did not initially plan for a prediction-market deal this year, but held discussions with multiple platforms.

However, USTA CEO Craig Tiley, who joined in February after a decade at Tennis Australia, played a significant role in securing the deal for the 2021 tournament. An unusual aspect of the agreement is that the USTA is preventing other prediction-market platforms from advertising in the facility or on TV, including ESPN, where the tournament is broadcast.

Kalshi's blog post listed Aryna Sabalenka as the favorite to win the women's singles at 23%, with Coco Gauff and Iga Świątek as close contenders. As of early Sunday, about $1.5 million had been placed on the women's singles winner. Despite not being on the US Open's list of official partners, the USTA proceeded with the deal. No traditional sportsbooks are listed as official partners.

The ATP Tour, which oversees the men's professional tennis tour and rankings, has no direct role in operating the US Open. However, it has separately spoken with the Commodity Futures Trading Commission about prediction-market regulation, offering recommendations that would strengthen the proposed rules, such as a prohibition on event contracts related to player injuries and officiating decisions.

Prediction-market platforms have been pursuing sports partnerships despite questions about the legality of sports-event contracts under federal framework or state regulation. Kalshi has team-level deals with NHL and MLB, and MLB's Yankees, while Polymarket has agreements with MLB and the Yankees. The NFL and NBA remain without prediction-market deals.