The World Cup is driving record-breaking activity on prediction markets, with popular platforms Kalshi and Polymarket reporting their highest trading volumes to date. Just days ahead of Sunday’s final, the Argentina–Spain contract has become the single largest market in the platforms’ history, while overall World Cup trading has outpaced other major sports-related contracts.
According to data shared by Kalshi, the contract for the outcome of the Argentina–Spain final, which went live Wednesday following Argentina’s win over England, has already surpassed $1.27 billion in trading volume. As of mid-day Friday, bets on Kalshi showed the Spanish team with 61% odds to prevail over Lionel Messi’s squad.
As of Tuesday morning, total trading across World Cup contracts had exceeded $25 billion—dwarfing volumes seen in other major sports markets, including roughly $2 billion for the NBA finals and $1 billion for the Super Bowl.
Polymarket has seen a similar surge in activity, with the Argentina–Spain contract reaching nearly $3 million in trading volume as of Friday. The platform told Fortune that more than 64,000 users had engaged with the match page three days before the final, signaling deep liquidity. Its World Cup Winner market has generated $4 billion in cumulative trading volume since launching in July 2025, making it the largest single market in Polymarket’s history and surpassing the 2024 U.S. presidential election. In June alone, the platform recorded nearly $11 billion in global monthly notional volume, largely driven by World Cup trading.
Prediction markets are not simply riding a World Cup wave. The tournament is reinforcing their broader ascent in the United States, where they are gaining traction as an accessible way to trade on real-world outcomes. These platforms allow users to take small positions directly from their phones, across markets that range from sports to politics. For many fans, these markets have become part of the standard playbook for engaging with major events, alongside traditional sportsbooks and fantasy leagues.
Mixed accuracy
Prediction markets can be used to gauge public sentiment and assign probabilities to future events. But unlike interest rate decisions, where traders can draw on economic data, or political elections, where polling and sentiment offer clearer signals, sports outcomes are far less predictable. Soccer in particular has produced some of the most surprising results in modern sports, which makes it a uniquely difficult arena for forecasting.
As a result, Kalshi and Polymarket’s World Cup contracts have shown mixed accuracy in predicting match outcomes. Two of the most closely watched semifinal matchups this week were France vs. Spain and Argentina vs. England. Early market pricing ahead of kickoff did not end up matching the eventual results.
In both matches, Kalshi markets initially gave roughly a 10% edge to the team that ultimately lost. Polymarket mirrored that pattern, though with a smaller percentage gap. In France vs. Spain, odds flipped about 20 minutes into the game, just before Spain scored its first penalty goal. England vs. Argentina was more volatile, with the odds largely tracking whichever team was ahead on the scoreboard. Results were especially unpredictable, given the caliber of all four teams. In earlier rounds, however, market predictions tended to be more accurate.
When Morocco faced France in the quarterfinals, Kalshi bettors favored Kylian Mbappé’s side at 76%, while Polymarket users put the team at 62%. Ahead of Argentina’s match against Switzerland, the odds were tilted toward Messi’s team. Spain’s matchup against Belgium was similar, with Lamine Yamal’s side favored at 73% on Kalshi and 59% on Polymarket. Only in Norway vs. England was the gap slightly smaller, favoring the latter team.
The World Cup has sparked an unprecedented surge in activity on prediction markets, with platforms like Kalshi and Polymarket reporting record trading volumes. As the tournament nears its final match, the Argentina–Spain contract has emerged as the largest in the history of these platforms, surpassing other major sports-related contracts.
Kalshi’s data indicates that the outcome contract for the Argentina–Spain final, which became available following Argentina’s victory over England, has already exceeded $1.27 billion in trading volume by Friday afternoon. As of that time, Kalshi’s odds favored Spain with a 61% likelihood of winning against Argentina, led by star player Lionel Messi.
Overall, the total trading for World Cup contracts has surpassed $25 billion, significantly outpacing other major sporting events. For context, the NBA Finals and Super Bowl generated approximately $2 billion and $1 billion in trading volume, respectively.
Polymarket is experiencing a similar trend, with the Argentina–Spain contract reaching nearly $3 million in trading volume by Friday. The platform reported that over 64,000 users had engaged with the match page just three days before the final, highlighting strong market liquidity. Polymarket’s World Cup Winner market has amassed $4 billion in cumulative trading volume since its launch in July 2025, making it the platform’s largest market to date, even surpassing the 2024 U.S. presidential election. In June alone, Polymarket recorded nearly $11 billion in global trading volume, largely attributed to World Cup-related activities.
The rise of prediction markets is not solely due to the World Cup; these platforms are gaining popularity in the United States as a means of trading on real-world outcomes. They enable users to make small bets directly from their smartphones across various markets, including sports and politics. For many fans, engaging with these markets has become a common practice alongside traditional betting and fantasy sports.
However, the accuracy of prediction markets can be inconsistent. While they can provide insights into public sentiment and assign probabilities to future events, sports outcomes, especially in soccer, are notoriously unpredictable. High-profile matches often yield surprising results, which complicates forecasting efforts.
Kalshi and Polymarket’s World Cup contracts have demonstrated mixed accuracy in predicting match outcomes. For instance, during the recent semifinals, market predictions did not align with the actual results. In both the France vs. Spain and Argentina vs. England matches, early market pricing favored the losing teams. Kalshi’s markets initially gave a 10% edge to the teams that ultimately lost, while Polymarket showed a similar trend, albeit with a narrower margin. For the France vs. Spain match, the odds shifted dramatically about 20 minutes into the game, shortly before Spain scored its first penalty. The England vs. Argentina match was even more volatile, with odds fluctuating according to which team was leading at any given moment. The unpredictability was heightened by the high skill levels of the teams involved.
In contrast, market predictions in earlier rounds of the tournament tended to be more accurate. For example, prior to the quarterfinal match between Morocco and France, Kalshi bettors favored France with a 76% likelihood of winning, while Polymarket users assigned a 62% probability to the French team. Similarly, Argentina was favored against Switzerland, and Spain had an edge over Belgium, with Kalshi and Polymarket showing respective probabilities of 73% and 59% for Spain.
Overall, the World Cup has significantly boosted engagement and trading on prediction markets, reflecting a growing interest in this form of entertainment and speculation. While the accuracy of predictions can vary, the excitement surrounding the event has undeniably drawn many participants to these platforms, marking a notable trend in sports betting and market participation.
