When Argentina and Spain take the field on Sunday for the World Cup final, more than $5.55 billion will be riding on the winner on the prediction markets Polymarket and Kalshi.
People are also betting millions on who wins third place and the Golden Boot award for top scorer. Others are wagering on what the announcers might say or whether it will be the final tournament for the Argentina team captain, Lionel Messi.
The event has helped drive new users to the prediction markets, which have grown rapidly and transformed into a cultural phenomenon in recent months. The sites allow users to wager on the outcome of just about anything, from elections to details about Taylor Swift’s wedding to the winner of the reality-TV show “Survivor.”
Prediction market users are poised to make the World Cup the largest gambling event in history, analysts said. In June, total wagers on the platforms topped $50 billion for the first time, much of it driven by the soccer tournament, according to data from Dune Analytics, a crypto data tracker. That was up from about $2 billion the same month a year ago.
The performance of prediction markets during the World Cup has “surpassed every estimate that any of us have projected,” said Chad Beynon, a gaming and lodging analyst at the financial services firm Macquarie Group. He estimated that the World Cup had helped quadruple monthly trading volumes across both platforms.
Nearly 270,000 people downloaded the Kalshi app the week the tournament began, according to data shared by the company from Apptopia. Two weeks earlier, it had about 60,000 downloads.
Isaac Arizmendi, a Mexico team fan, downloaded Polymarket for the first time in June to bet on the tournament. The 24-year-old, who lives in Los Angeles and works in social media marketing, said he was wagering on the winner of every game.
“You have a purpose watching that game,” he said. “You bond with people at the bar, like, ‘Ah, you put money on the game, too?’ Pow!”
The explosive success of Kalshi and Polymarket — which earn revenue by collecting fees on each bet — has drawn attention. Mark Zuckerberg, the chief executive of Meta, has directed employees to create a prediction markets app.
Traditional gambling firms like FanDuel and DraftKings have started offering their own prediction markets, as has Gemini, a cryptocurrency exchange. Trump Media & Technology Group, President Trump’s social media business, has also rolled out plans for prediction markets.
The growth has also stoked scrutiny over concerns about insider trading and other problematic behavior on the platforms.
More than a dozen states have sued Kalshi and Polymarket, citing local laws that ban sports betting. In late June, a judge in Michigan ordered a temporary halt to Kalshi’s offerings in the state after its attorney general, Dana Nessel, sued the company, accusing it of violating state sports betting laws.
Kalshi’s operations are “unlicensed” and “predatory,” Ms. Nessel said in a statement.
Still, the markets have surged, with a boost from the World Cup. The tournament started June 11 with an expanded roster of 48 teams playing 104 games — even more to wager on than usual. The markets have also benefited from increased interest in soccer in the United States, which was one of the hosts of the tournament.
Polymarket and Kalshi have spent heavily on marketing throughout the event. Polymarket launched an ad campaign featuring the music producer Rick Rubin and the rapper Future pegged to the U.S. team’s making it to the final. “Can the U.S. win it all?” Future asked in the ad.
Kalshi became an official partner of FIFA, soccer’s global governing body, through a branding and product deal with the World Cup’s existing prediction market partner, ADI Predictstreet, a little-known platform. Kalshi’s logo was displayed around the field at game time, and its ads blanketed commercial breaks.
After seeing ads for Kalshi “everywhere,” Trisha Kvien, 42, downloaded the app at the start of the World Cup. Ms. Kvien, who works in advertising technology in central California, put $25 on the United States to beat Paraguay during the group stage. She won about $11, and was hooked.
She used Kalshi when she attended the Spain-versus-Belgium game last week in Los Angeles, wagering on how many corner kicks both teams would take — and even got the rest of the crowd into the action counting with her. (She lost.)
“I’m not betting money that I’m not willing to lose,” she said, adding: “I’m putting it in for the experience and the good time. And if I win some money off of it, I’m having an even better time.”
