Prediction markets significantly expanded their presence during the 2026 FIFA World Cup, accounting for an estimated 27% of legal U.S. sports betting activity as trading volumes reached record levels.
According to data from H2 Gambling Capital, prediction markets’ share of legal U.S. sports betting volume rose from approximately 9% at the beginning of 2026 to 27% during the first month of the tournament. While prediction markets and traditional sportsbooks measure activity differently, the figures indicate growing adoption of event-based trading platforms.
World Cup Boosts Prediction Market Growth
Kalshi, the largest U.S. prediction market exchange, reported record trading activity throughout the tournament, with volumes surpassing previous highs set during the NBA playoffs.
The company also launched an extensive marketing campaign featuring stadium advertising, partnerships with ADI Predictstreet, and integrations that displayed contract odds in selected ChatGPT World Cup searches. Promotional campaigns involving football personalities, including Luka Modrić, José Mourinho, and the Argentina national team, further increased brand visibility.
Kalshi stated that the World Cup campaign attracted 3 million new users and generated more than US$1.2 billion in trading on its tournament winner market.
Competitive Pressure on Sportsbooks
Industry analysts said the rapid growth of prediction markets is increasing competitive pressure on traditional sportsbook operators.
Research from Bernstein noted that the popularity of platforms such as Kalshi could encourage established sportsbooks to introduce similar products as demand for event-based trading continues to grow. Prediction market operators have also benefited from operating under the oversight of the Commodity Futures Trading Commission, while continuing to defend their products against regulatory challenges from several U.S. states.
Lower Trading Costs Highlight Competitive Advantage
A separate analysis by Citizens JMP Securities found that prediction markets generally offered lower implied margins than traditional sportsbooks during the World Cup.
Among the operators reviewed, Polymarket recorded the lowest average implied vig at 2.70%, followed by Kalshi at 4.71%. Traditional sportsbook operators posted higher averages, including DraftKings at 4.97%, FanDuel at 5.07%, BetMGM at 5.64%, and Fanatics at 6.14%.
Analysts said stronger liquidity, increased participation from market makers, and greater competition among liquidity providers have helped improve pricing on prediction markets. They added that if these trends continue, prediction markets could further strengthen their competitive position by attracting more sophisticated traders and additional liquidity.
