Prediction market platforms Kalshi and Polymarket recorded a combined monthly trading volume of $44.8 billion in June, a 75% increase from May, largely fueled by the ongoing 2026 FIFA World Cup. Kalshi led the surge with an 87.4% jump to $31.5 billion, while Polymarket’s non-U.S. platform attracted $10.26 billion (up 45%) and its U.S. arm reached $3.04 billion. The tournament transformed prediction markets into a mainstream betting venue, with Kalshi’s World Cup winner market drawing over $832 million in bets and France emerging as the favorite.
The spike underscores a shift from politics to sports as the primary growth engine. Polymarket’s standalone World Cup winner contract surpassed $3 billion in lifetime trading volume before the tournament’s later stages, and individual match contracts generated between $500,000 and $2 million each. The expanded 48-team format created hundreds of tradable markets, attracting institutional liquidity and tighter spreads. Major tech companies, including Meta, are exploring partnerships with the platforms, while Bernstein analysts project the sector could eventually exceed $1 trillion in annual volume.
Yet the rapid growth has intensified legal scrutiny. Regulators in more than a dozen U.S. states have challenged sports-related contracts, arguing they resemble unlicensed betting. Kalshi and Polymarket, backed by the Commodity Futures Trading Commission, maintain that federal oversight permits their operations. The World Cup concludes on July 19, likely sustaining high activity levels and keeping prediction markets in the spotlight.
