Kalshi has been named the Official Prediction Market Partner of the US Open under a multi-year United States Tennis Association agreement that begins with the 2026 Singles Main Draw. The partnership gives Kalshi a presence across US Open digital platforms and on-court signage. USTA CEO Craig Tiley cast the deal as a way to push fan engagement while safeguarding competitive integrity, and Kalshi co-founder and CEO Tarek Mansour said tennis is among the fastest-growing sports on the platform, where tennis-related trading volume is up 25 times year over year and the company serves millions of users. Together the sides built a comprehensive integrity framework that restricts markets posing integrity risks, including those on umpire decisions and code violations, and Kalshi executed a confidential data-sharing agreement with the International Tennis Integrity Agency for real-time market surveillance alongside USTA monitoring, education, and compliance enforcement. The public announcement follows earlier reporting that exclusivity bars rival platforms from advertising at Flushing Meadows and on ESPN, after Tiley advanced the 2026 deal ahead of a prior 2027 evaluation timeline. DoubleZero’s DZ Edge fiber feed for Kalshi order books has been live since August 12, delivering Level 1 and full-depth Level 2 data on sports markets and crypto perpetual futures, while about $1.5 million had been wagered on the women’s singles winner as of Sunday afternoon, rising to approximately $1.6 million by early Monday morning, with Aryna Sabalenka as the 23% favorite.