The U.S. Open struck a last-minute exclusive prediction-market deal with Kalshi as the tournament’s main draw began on Sunday. The agreement took effect immediately, after it was not formally locked in until qualifying rounds ended last week.
Front Office Sports reported that the USTA had not originally planned to have a prediction-market partner in place this year. In recent weeks, it had spoken with multiple platforms about match-integrity concerns and about possible deals for next year and beyond, and new chief executive Craig Tiley played a major role in getting the arrangement done for this year. The financial terms were not disclosed.
One unusual part of the deal is that the USTA is blocking rival prediction-market advertising inside the venue and on television coverage, including on ESPN. Kalshi was still absent from the US Open’s official partner list on Sunday afternoon, even as the company published a women’s singles market that put Aryna Sabalenka at 23%, Coco Gauff at 16% and Iga Świątek at 15%. Roughly $1.5 million had been placed on the winner market by early afternoon, and Kalshi’s page said it was not affiliated with the U.S. Open or the WTA.
The move lands amid a broader regulatory fight over prediction markets. The Block reported that Kalshi suffered a setback on Friday in the Ninth Circuit in its Nevada dispute, while Stanford Law said states including New Jersey and Washington argue that sports-indexed contracts are not legitimate commodity markets under the Commodity Exchange Act. In June, the CFTC also proposed rule changes for event-contract derivatives often described as prediction markets, with public comments due by July 27.
