Prediction Markets Captured an Estimated 27% of US Sports Event Volume During the World Cup
Updated September 3, 2026
Updated September 3, 2026
The World Cup is over, and Spain are the winners. Rightfully so.
But perhaps the biggest winners are prediction markets as a whole, as the 2026 World Cup may be remembered as the tournament that pushed prediction markets firmly into the mainstream.
Prediction-market platforms generated activity equivalent to an estimated 27% of legal U.S. sportsbook volume during the World Cup, according to an analysis from H2 Gambling Capital reported by Bloomberg. That figure was up from approximately 9% at the beginning of 2026, highlighting how rapidly sports event trading has expanded over the past seven months.
Platforms such as Kalshi and Polymarket allowed users to trade contracts covering match results, tournament progression, individual awards and the eventual World Cup champion. The tournament produced record activity across the sector as millions of contracts changed hands throughout the group stage and knockout rounds.
But before treating this as a black-and-white number, it is important to note that this figure should be taken with a pinch of salt, at least for now.
The 27% figure should be viewed as an industry estimate rather than a final audited market-share calculation. H2 based its analysis on publicly available data from the tournament’s first month, while major sportsbooks had not yet released their complete internal World Cup figures. Prediction-market trading volume and sportsbook handle are also calculated differently, making a direct comparison imperfect.
Even with those qualifications, the estimate offers one of the clearest indications yet that prediction markets are beginning to challenge established sports platforms for consumer attention and trading activity.
The growth was already visible midway through the tournament. By June 22, Kalshi had reportedly generated approximately $2.9 billion in World Cup trading volume, while Polymarket’s tournament markets had produced around $2.5 billion since launching in July 2025. Robinhood also reported that more than 400 million contracts had been executed through its Rothera exchange since the World Cup began.
Those figures continued to rise as the tournament entered its knockout stages, with high-profile matches and championship markets attracting increasingly large volumes. The result was a World Cup that did not simply deliver a temporary spike in activity – it provided the strongest evidence yet that sports could become one of the prediction-market industry’s primary growth drivers.
Kalshi was one of the tournament’s biggest winners. By July 14, World Cup contracts on the platform had reportedly generated more than $25 billion in trading volume, while the Spain–Argentina final alone finished at approximately $1.29 billion.
The figures show the scale of the surge, although trading volume should not be confused with unique customer deposits. Contracts can change hands several times before a market settles.
Polymarket also recorded extraordinary activity. Its World Cup Winner market generated approximately $4.33 billion in trading volume after remaining open for more than a year.
The market ultimately resolved in favor of Spain and became the largest individual market in Polymarket’s history.
H2 Gambling Capital compared publicly available prediction-market activity with estimated legal U.S. sportsbook handle during the World Cup.
The comparison is imperfect because prediction-market volume and sportsbook handle are calculated differently. Complete World Cup figures from major sportsbooks were also unavailable at the time.
So, again – too early to tell what this actually means. The 27% figure should therefore be viewed as an estimate of the sector’s rapid growth, rather than an audited market-share total.
The bigger question is whether World Cup users will continue trading after the tournament.
Few events can match the World Cup’s month-long schedule and global appeal. However, the tournament showed that prediction markets can attract mainstream sports audiences and generate substantial liquidity.
The World Cup may not have changed the industry overnight, but it offered the clearest evidence yet that prediction markets are becoming a permanent part of the U.S. sports landscape.
