Kalshi’s U.S. web traffic surged sharply over the past year, reaching 15.4 million visits in July, up about 1,520% from just under 1 million in August 2025. The U.S. still drives most of its traffic, accounting for nearly 80% in July. Growth has been even stronger in trading activity: monthly notional volume hit about $40 billion in August, up roughly 4,500% from a year earlier, and Kalshi represented nearly 79% of the prediction-market industry’s $50.7 billion monthly volume. Sports contracts made up 83% of Kalshi’s July trading volume. The expansion comes amid legal fights over whether Kalshi’s sports event contracts are federally regulated or subject to state gambling laws, including a Supreme Court dispute led by New Jersey. Traffic also rose from restricted jurisdictions such as Canada and the UK.