Celebrities Promoting Prediction Markets: LeBron, Messi, Sydney Sweeney

Kalshi has been particularly aggressive with celebrity marketing, but Polymarket, Novig, Underdog and OG Prediction Markets have also brought recognizable names into the industry.

Here is a look at some of the biggest celebrity prediction market partnerships and advertising campaigns so far.

Celebrities Who Have Promoted Prediction Markets

The relationships are not all the same. Some celebrities are formal ambassadors or investors, while others have simply been hired to appear in advertising campaigns.

Giannis Antetokounmpo, for example, is an investor in Kalshi in addition to starring in its advertising. Sydney Sweeney joined Novig as both a strategic partner and equity holder. OG Anunoby was formally announced as a brand ambassador for OG Prediction Markets.

Kalshi has also used celebrity advertising on a particularly large scale. Its 2026 World Cup marketing included endorsement deals with Clint Dempsey, Memo Ochoa, Marcelo, Falcao, Rio Ferdinand, David Villa, Raphaël Varane and Ángel Di María, alongside its sponsorship of the Argentine national team featuring Lionel Messi.

Polymarket's Celebrity-Filled Campaign

Polymarket made its biggest celebrity move in September 2026 when LeBron James announced a partnership with the platform.

James was the centerpiece of the company's "Polymarket HQ" football-season campaign, but he was far from the only famous face involved.

The commercial also included:

• Derek Jeter — MLB and New York Yankees legend
• Eli Manning — two-time Super Bowl-winning NFL quarterback
• Sue Bird — WNBA basketball legend
• Richard Sherman — former NFL cornerback
• Reggie Bush — Heisman Trophy winner and former NFL running back
• Rajon Rondo — former NBA point guard
• Spike Lee — filmmaker and prominent New York sports personality
• Emily Ratajkowski — model and actress
• Alexandra Daddario — actress
• John Leguizamo — actor and comedian
• Craig Robinson — actor and comedian

Polymarket itself described the campaign as bringing together "sports legends and cultural icons," with James, Manning, Jeter, Lee, Bird, Sherman and Rondo among the names it highlighted.

It is worth making a distinction here: appearing in a Polymarket commercial does not necessarily mean every person in it has a long-term sponsorship deal with the company. LeBron James has publicly announced a partnership, while many of the other celebrities are better described as campaign appearances.

Which Prediction Market Has the Most Celebrity Partnerships?

Kalshi appears to have made the biggest push into celebrity marketing so far.

Its campaigns have crossed basketball, football, soccer, tennis, golf, movies and music. Timothée Chalamet signed a multi-year deal, J Balvin entered a broader creative partnership, Luka Modrić became a global ambassador, and Giannis Antetokounmpo combined an equity investment with advertising appearances.

Kalshi has continued adding sports names as well. Pete Sampras and Marshawn Lynch both appeared in new campaigns in September 2026, following earlier spots featuring Bryson DeChambeau and Terrell Owens.

Polymarket has taken a slightly different approach, making LeBron James the centerpiece of a large ensemble campaign.

Novig has gone in another direction. Rather than building a long list of ambassadors, its highest-profile partnership is with Sydney Sweeney, who also received equity in the sports-focused prediction market.

Why Are Prediction Markets Using Celebrities?

The strategy looks increasingly familiar.

Sportsbooks spent years using athletes, actors and other celebrities to build brand recognition as legal sports betting expanded across the United States. Prediction markets are now competing for many of the same sports fans.

A recognizable name can also help explain an unfamiliar product without actually explaining much at all. Someone who has never used a prediction market may not know the difference between an event contract and a sportsbook wager, but they probably know LeBron James or Lionel Messi.

That matters as companies including Kalshi, Polymarket and Novig try to move prediction markets beyond their relatively niche roots and turn them into mainstream consumer brands.

The trend is accelerating, too. Around the start of the 2026 NFL season, prediction market companies dramatically increased their advertising activity, with LeBron's Polymarket campaign and Sweeney's Novig campaign launching within days of each other.

For prediction markets, the celebrity arms race may only be getting started.