Kalshi US traffic jumps 1,520% as trading volume hits $40 billion in August

The major prediction market platform Kalshi reported a massive spike in user engagement and transaction activity over the last year. In July, the platform recorded 15.4 million visits from the United States, which represents an increase of approximately 1,520% compared to less than 1 million visits in August 2025. US users accounted for nearly 80% of all traffic in July, up from 72.8% in August 2025. This heavy concentration on the domestic market occurred while Kalshi faces significant legal challenges regarding whether its sports event contracts require federal oversight or comply with state gambling laws; New Jersey has taken this dispute to the US Supreme Court. Simultaneously with the traffic surge, actual trading activity accelerated sharply. Monthly notional trading volume reached about $40 billion in August, a rise of roughly 4,500% from $874 million a year prior. Across the prediction-market industry, monthly notional volume climbed to $50.7 billion from approximately $2 billion during the same period. Kalshi accounts for nearly 79% of the total latest volume.