Prediction markets such as Polymarket and Kalshi, which frame betting on sports, politics and world events as financial trading, have exploded in popularity in the US and are now drawing growing interest in the UK, fuelled by events like the World Cup and the Clacton byelection. Their rapid growth stems largely from the patchy way US states have regulated sports betting since a 2018 Supreme Court ruling lifted a federal ban, allowing these platforms to present themselves as regulated financial products overseen by the Commodities and Futures Trading Commission rather than gambling operators, letting them operate in states where sports wagering remains restricted.

Registered prediction markets are estimated to have attracted trading volumes of at least $45bn during the World Cup, according to figures the platforms themselves publish, with California and Texas among the large, unregulated states giving them a "free run" across a combined economy worth around $7tn. However, the article cautions that these headline figures overstate real risk, since "trading volume" counts every resale of a betting position rather than fresh money staked; analysts at Eilers & Krejcik Gaming suggest actual World Cup stakes were considerably lower. The piece also notes that UK gamblers can already access these platforms with relative ease, sidestepping domestic regulation, raising questions about whether a similar boom could take hold in Britain.