Kalshi and Polymarket's combined volume surges 75% to $45 billion in June amid World Cup fever

Kalshi and Polymarket saw their combined trading volume soar last month as the FIFA World Cup 2026 continues to drive bettors into prediction markets.

According to The Block's data dashboard, Kalshi, Polymarket, and Polymarket US recorded $44.8 billion in combined monthly trading volume in June, marking a 75% surge from May's $25.66 billion monthly volume.

Among the three, Kalshi saw the largest month-over-month increase in volume, growing 87.4% to $31.5 billion from $16.81 billion. 

Polymarket's main, non-U.S. platform attracted $10.26 billion worth of volume last month, up 45% from the previous month's $7.08 billion.

Polymarket had seen a steady decline in monthly volume from March through May, while its U.S.-regulated platform sustained an upward trend. Polymarket US reported $3.04 billion in monthly volume last month, up from $1.77 billion in May.

World Cup fever

The sharp volume increase can be attributed to the FIFA World Cup, which kicked off on June 11. Kalshi's FIFA World Cup Winner prediction market has drawn more than $832 million in bets, with about 35% pegging France as the winner.

World Cup prediction markets on Polymarket are also gaining significant traction, with event contracts on each game attracting $500,000 to $2 million in volume. This year's World Cup is scheduled to end on July 19.

Meanwhile, these prediction market platforms are facing legal scrutiny in the U.S. over sports-related contracts. More than a dozen state-level authorities have taken legal action against Kalshi and Polymarket, accusing them of offering unlicensed sports betting or gambling to residents.

The platforms, alongside the Commodity Futures Trading Commission, argue that federal regulation permits them to offer sports-related markets, overriding state-level jurisdiction.

Source: https://www.theblock.co/post/406983/kalshi-polymarket-volume-45-billion