LeBron James announced a partnership with prediction market platform Polymarket through a video posted to X on September 5, 2026, with the company promising additional details on Tuesday. The clip shows James at what he describes as Polymarket headquarters, touring floors dedicated to politics, crypto, economy, culture, weather, esports, and technology before arriving at the sports section.
The deal marks James's pivot from sportsbook DraftKings, where he held an endorsement contract that ran from 2024 until it expired earlier this summer. His move to Polymarket comes as prediction markets have grown substantially, with monthly sector volume reaching $20 billion by January 2026, up from approximately $1.2 billion in early 2025.
The NBA permits players to endorse prediction markets but prohibits them from promoting contracts tied to NBA games. The NFL and PGA Tour reportedly ban such endorsements outright. James himself became a betting market during the summer, with his next team drawing more than $245 million in trading volume.
Other athletes have already engaged with prediction market platforms. Giannis Antetokounmpo became a shareholder in Kalshi earlier in 2026, intensifying competition between the two leading operators. Professional leagues have also moved into the space, with Major League Baseball naming Polymarket as its official prediction market provider and the NHL striking deals with both operators in October 2025.
The expansion has attracted regulatory scrutiny. Baltimore sued both operators in August 2026 for allegedly operating as unlicensed sportsbooks, while New York sued Kalshi in July for more than $36 billion. Despite legal challenges, investor confidence has remained strong. Polymarket sought $400 million at a $15 billion valuation in April 2026, significantly higher than the $9 billion valuation from October 2025. Intercontinental Exchange, which owns the New York Stock Exchange, committed $2 billion to the company.
Polymarket has broadened its offerings beyond politics and sports, adding Pokemon card markets in August 2026. The James partnership terms remain undisclosed, though analysts will watch whether his involvement converts casual fans into active traders as the football season begins.
