Trading volume on major prediction market platforms has surged in recent months as activity across sports, politics and cryptocurrency markets accelerated on both Kalshi and Polymarket.
Combined monthly global trading volume on the two platforms rose from less than $5 billion in September 2025 to about $24 billion in April 2026, according to a Pew Research Center analysis of data from digital assets media and information firm The Block.
The report showed that total prediction market trading volume now exceeds average monthly legal U.S. sportsbook wagering levels recorded during 2025. Legal sportsbooks in the United States handled around $14 billion per month on average last year.
Prediction markets allow users to trade contracts tied to real-world outcomes including elections, sports games, cryptocurrency events, weather conditions and public appearances. Contracts are priced between $0 and $1 and are designed to reflect the probability of an event occurring. A contract priced at 40 cents is intended to represent a 40% chance of the event happening. Winning contracts settle at $1 once markets are resolved.
In the United States, Kalshi is regulated by the Commodity Futures Trading Commission. Polymarket International is not regulated by the CFTC, though Americans can access it using VPN services. Polymarket US, which is regulated by the CFTC, recorded $1.3 billion in trading volume in April 2026 compared with $9 billion on Polymarket International during the same month.
Sports, politics and cryptocurrency trading accounted for most activity across both platforms since July 2024. Those three categories represented 91% of global trading volume on Kalshi and 90% on Polymarket during the period reviewed.
Sports trading dominated activity on Kalshi, making up 80% of total trading volume since July 2024. On Polymarket, sports accounted for 39% of total volume, while cryptocurrency represented 20% and politics represented 32%.
Political trading activity increased sharply around the 2024 U.S. presidential election. Political markets accounted for 90% of Kalshi trading volume and 65% of Polymarket trading volume during October and November 2024. The report noted that Kalshi had not yet introduced sports trading at that time.
The platforms also host trading on smaller event categories including public appearance “mention markets” and weather events in cities around the world, though those markets represent a relatively small share of overall trading activity.
