Polymarket and Kalshi Hit $150B Lifetime Volume as Prediction Markets Face Growing Scrutiny

Combined Trading Volume Crosses Major $150 Billion Milestone

Polymarket and Kalshi have reached a combined lifetime trading volume of $150 billion as of April, marking a major milestone for the fast-growing prediction markets sector. The figure highlights rapid expansion in event-based trading, even as monthly activity shows early signs of cooling.

April Trading Activity Falls After Months of Record Growth

April marked the end of a seven-month streak of record-high monthly volumes across the sector. Overall activity declined compared to March, driven mainly by reduced trading on Polymarket’s global platform. However, its US-focused operations continued to grow, while Kalshi also posted gains.

The number of active Polymarket traders fell to around 643,000 in April, down from more than 733,000 in March. This drop coincided with lower dollar volumes and reduced notional trading across both platforms.

Regulatory Environment Shapes Prediction Market Expansion

Despite the monthly slowdown, both platforms remain dominant players in the sector. Kalshi has gained traction in sports and event-based markets after a key legal victory against the Commodity Futures Trading Commission in 2024, which allowed it to offer election-related contracts.

That ruling also influenced broader industry momentum, helping prediction markets gain legitimacy under federal oversight while expanding access in the US.

Strong Valuations and Institutional Interest Continue

Kalshi recently raised funding at a $22 billion valuation, while Polymarket previously backed by Intercontinental Exchange is reportedly targeting a $15 billion valuation. Both platforms are also working to strengthen compliance measures, including efforts to prevent insider trading as regulatory scrutiny increases.

Overall, while short term trading activity has cooled, the sector continues to scale rapidly, reflecting growing interest in event-based financial markets and their role in price discovery.