The FIFA World Cup has driven record trading volumes across prediction market platforms, underlining the growing overlap between sports betting and event-contract exchanges.
Kalshi recorded more than US$31bn in notional trading volume in June, up more than 70 per cent from US$17.9bn in May, according to CNBC, which cited user-collected data from Dune Analytics. The platform has handled daily volume above US$1bn since the World Cup began on June 11.
Polymarket’s international event-contract exchange also reached a record monthly high, with more than US$10.8bn in notional trading volume in June. Its US platform generated more than US$3.5bn, compared with US$1.77bn in May.
Rothera, the event-contract exchange launched in June as a joint venture between Susquehanna International Group and Robinhood, recorded more than US$2bn in notional trading volume during its first month. CNBC reported that Rothera accounted for around seven per cent of US prediction market volume, citing Bank of America.
The World Cup has become a major test of the prediction market model as platforms use sports contracts to build liquidity, acquire customers and demonstrate market resilience during periods of heavy trading activity.
Kalshi promoted World Cup trading through its mobile app, while Polymarket launched a competition offering up to US$2m for a perfect knockout-stage bracket. The surge in trading has also lifted open interest, with Kalshi above US$1bn and Polymarket’s open interest just under US$400m, according to CNBC.
The growth of sports-related event contracts is attracting closer attention from regulators, sportsbooks, exchanges and institutional investors. Prediction market operators argue that event contracts are financial instruments designed to trade on real-world outcomes, while critics say sports contracts increasingly resemble sportsbook products offered through a different regulatory structure.
Asaf Meir, chief executive of market integrity company Solidus Labs, told CNBC that the World Cup represents a key pressure test for prediction markets as regulators and institutions assess whether platforms can manage sustained high-volume trading.
“Is it safe enough? Is it mature enough? Does it have enough volume?” Meir said, describing the questions now being asked by outside observers.
For sportsbook operators and gambling regulators, the rise in World Cup trading volumes sharpens an already difficult policy question. Sports event contracts are competing for customer attention in the same entertainment and wagering economy as licensed sportsbooks, but in the US they sit inside a different regulatory conversation.
The World Cup surge suggests prediction markets are no longer a niche political or financial forecasting product. Sport is becoming one of the main drivers of liquidity, customer acquisition and regulatory scrutiny.
