FIFA World Cup predictions have emerged as the dominant force in prediction markets, with Polymarket's tournament winner market alone holding $2 billion in bets and Kalshi running 48 markets on the same question while collecting record fees. According to BeInCrypto's Dune dashboards, sports trading volume reached $10.44 billion in May 2026, representing a record month for prediction markets. By Binance Research's accounting, prediction markets turned over a record $31.2 billion in May, up roughly 15% from January, with Kalshi capturing 58% of that flow and Polymarket accounting for 28%. The industry's open interest reached $1.3 billion during this period.
The platforms have adopted different approaches to World Cup coverage, with Polymarket concentrating $2 billion in lifetime volume across a single tournament-scale market while Kalshi spreads flow across 48 match-level markets. In May, Kalshi collected $137.86 million in trading fees compared to Polymarket's $28.07 million, representing a nearly five-to-one revenue gap. BeInCrypto's data shows that while Kalshi's biggest month of 2026 was driven by sports trading, the platform's elections category managed only $173.66 million that month, roughly 60 times less than sports volume. The concentration is evident across Polymarket's entire year, with sports leading every weekly category split in 2026.
Despite the World Cup dominance, overall prediction market activity has shown cooling trends. According to BeInCrypto's data, by June, total activity had cooled about 70% to $5.91 billion, yet sports share climbed to 56.5% of the remaining volume. The platform's FIFA World Cup section spans more than 330 active markets, with the single biggest football market holding $2 billion in lifetime volume and $436 million in liquidity. Both platforms price World Cup odds identically, with Spain as the favorite at exactly 17%, and Kalshi pays 5.56x on Spain and France alike. The platforms' World Cup odds remain identical, with both pricing Spain as the favorite at exactly 17%.
The platforms' World Cup coverage strategies may determine their competitive positioning. Daily group-stage games favor Kalshi's match-level structure, while knockout drama should feed Polymarket's deep tournament pool, potentially shifting leadership week by week. BeInCrypto's data shows that sports have now beaten crypto on every venue tracked, including the crypto-native ones, with politics collapsing to a rounding error barely a year after carrying the industry. Traders should monitor whether kickoff revives total volume, whether the rebounding elections category claws share back from sports, and whether open interest continues building into the knockout stages. The outcome of the group stage may determine whether the prediction market boom has peaked before the first whistle.
