LeBron James Partners with Polymarket to Promote Prediction Markets

LeBron James is now the face of Polymarket’s sports ambitions. The prediction market platform announced on September 5 that James has signed on as its first individual athlete partner, with a campaign focused on football timed to launch the week of September 8. James teased the deal through a short video posted to X and Instagram, showing him inside a stylized “Polymarket HQ” elevator pressing the button for the “sports” floor.

This partnership marks a notable pivot in James’s endorsement portfolio, as he previously held a multi-year deal with DraftKings, the traditional daily fantasy and sportsbook giant, which has now expired. Instead of renewing with a legacy platform, James chose Polymarket, a blockchain-based prediction market built on Polygon where users trade outcome contracts on various events, including sports.

Polymarket is not alone in this competitive space; its main competitor, Kalshi, has been actively signing athlete endorsements, including Giannis Antetokounmpo and Lionel Messi. Over $43 million was traded on Polymarket’s markets surrounding James’s own free-agency decision earlier this year, highlighting the growing interest in prediction markets.

While the NBA allows players to endorse prediction market platforms, it restricts league-specific promotion. This means James can promote Polymarket’s football campaign without violating NBA rules, as promoting NBA-specific betting markets would be prohibited. This strategic choice enables both parties to leverage the massive audience of the football season while adhering to regulatory guidelines.

As Polymarket and Kalshi continue to stack celebrity endorsements, the regulatory frameworks they operate under differ significantly. Kalshi is CFTC-regulated and operates as a designated contract market, while Polymarket has faced its own regulatory scrutiny in the U.S., including a settlement with the CFTC in 2022.