Kalshi and Polymarket combined 2025 volume tops $44 billion
Kalshi and Polymarket generated a combined trading volume exceeding $44 billion in 2025, according to Kucoin and Odaily. Monthly volume on both platforms swelled from $2 billion in early 2025 to nearly $50 billion in June, with much of the activity concentrated in sports markets, Semafor reported. Kalshi operates as a designated contract market registered with the Commodity Futures Trading Commission (CFTC). Polymarket also holds CFTC registration through its acquisition of licensed exchange QCEX.
The volume figures give Congress live ammunition it lacked when a bipartisan Senate bill to ban sports event contracts was introduced in March. Sponsors can now cite billion-dollar scale as evidence that prediction markets have crossed from niche trading into mass wagering. Kalshi and Polymarket face a narrowing window to build credible self-regulation on insider surveillance and tax reporting before lawmakers draft rules for them.
The platforms that move first on compliance may shape any ban's final form or deflect it entirely. DraftKings and Robinhood are watching from their own regulated launches. A federal ban would strip the core sports vertical nationwide without waiting for courts to resolve state fights in New York, Michigan, Illinois, and New Mexico.