The million-dollar bets that won and lost in the World Cup so far.
The 2026 World Cup has driven unprecedented volume in prediction markets, with over $5 billion traded on the international Polymarket exchange and Kalshi, a regulated platform in the United States, according to a Bloomberg News analysis based on data from Dune Analytics and the companies' own records.
The tournament exposed bets worth millions of dollars in real time, with significant wins and equally substantial losses. The most emblematic case was that of a Polymarket user who bet on Belgium to beat Egypt and lost almost US$9 million due to the incorrect result.
Winners and losers
The most lucrative World Cup bet on Polymarket so far was placed by an account identified as “GRIMDRIP”. The user turned $6 million into $13,6 million with two bets on the Czech Republic against South Africa. Another bettor, under the nickname “mintblade”, doubled $7 million by predicting that Iran would not beat New Zealand.
The account “endlessFate” accumulated US$5,6 million on the match between Saudi Arabia and Uruguay and another US$2,7 million with Colombia's victory over Uzbekistan. However, the user's performance is not consistent; they recorded a loss of US$1,2 million betting on a draw between the United States and Paraguay in the week ending June 14th.
Of the 20 most profitable bets placed on Polymarket's international exchange in the last seven days, 18 were linked to the World Cup, according to company and blockchain records. In addition to match results, users bet on who will win the Golden Boot for top scorer (Frenchman Kylian Mbappé is the favorite) and whether President Donald Trump will reach the final (87% of bettors believe he will).
Profits, however, are not the norm for most. Research conducted by Jordan Bender and colleagues at Citizens Bank concluded that retail clients in prediction markets tend to lose money in the long run and perform worse than bettors at traditional bookmakers.
Growth of platforms
Kalshi recorded, for the first time, three consecutive days with daily trading volumes above US$1 billion, a result driven by the World Cup and the NBA Finals. The information was released by CEO Tarek Mansour at a Bloomberg event held on Tuesday (June 16).
DraftKings, which entered the betting markets in 2025, reported that last weekend was its best-performing weekend for event contracts since it began operations in the segment, even surpassing the Super Bowl in February. The company posted on social media that the total number of clients grew by more than 200% compared to the previous weekend, with trading volume increasing by 100% during the same period.
The ability to operate in American states where conventional sports betting is prohibited, such as California and Texas, has broadened the reach of these platforms. "Basically, the phenomenon that's happening here is that it's become a mess," said Bender, a gaming industry equity research analyst at Citizens.
Both DraftKings and Kalshi have increased their investments in advertising campaigns on social media and television. DraftKings is running ads that position its "sports app" as available throughout the United States. Kalshi, in turn, has partnered with athletes for the tournament, including Croatian midfielder Luka Modrić and Argentinian Lionel Messi.
“Everything we’re seeing so far during the World Cup suggests that the prediction markets continue on an aggressive growth trajectory,” stated Chris Grove, analyst at Eilers & Krejcik Gaming. The competition still has the knockout stages ahead, totaling 104 games.
