[DigitalToday reporter Jae-won Choi] U.S. website visitors to U.S. prediction market platform Kalshi surged more than 1,500 percent in less than a year. Trading volume also soared, centered on sports prediction contracts, drawing the attention of regulators and courts.

On Sept. 4 (local time), Cointelegraph analyzed Similarweb estimates and found Kalshi recorded 15.4 million visits in the United States in July. That was about a 1,520 percent increase from under 1 million in August 2025. The share of U.S. visitors in total traffic also rose to about 80 percent from 72.8 percent over the same period.

The rise in trading was even steeper. According to Dune Analytics, Kalshi’s monthly notional trading volume in August was about $40 billion, up about 4,500 percent from $874 million a year earlier. Total prediction market trading volume rose to $50.7 billion from about $2.0 billion over the same period, and Kalshi accounted for about 79 percent of recent volume.

Sports led the growth. In July, 83 percent of Kalshi’s trading volume came from sports-related contracts. Legal disputes are also growing over whether they should be treated as financial products overseen by the U.S. Commodity Futures Trading Commission, or as sports gambling regulated by U.S. states. New Jersey recently took the issue to the U.S. Supreme Court.

Overseas interest also increased quickly. Visits from Canada rose to about 450,000 from about 50,000, and the United Kingdom increased to 296,000 from 31,000. The two countries are regions where direct trading in Kalshi event contracts is restricted.

Still, in June Kalshi partnered with Canadian financial firm Wealthsimple to offer Canadian users about 4,000 eligible Kalshi contracts through a separate app, Wealthsimple Predict. With the rapid expansion in users and trading, competition over regulatory jurisdiction surrounding Kalshi is expected to intensify further.