Kalshi posted a record month for trading volume in June as the expanded FIFA World Cup boosted prediction market activity, while regulators intensified scrutiny in the US and Europe.

Kalshi and Polymarket processed nearly $45B in June trades, a 75% monthly jump driven by sports betting. Here's what the surge means for investors.

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