The American Gaming Association (AGA) estimates that Americans will legally wager $3.3 billion on the NCAA Division I Women’s and Men’s Basketball Tournaments this year, a 54% increase.

The continued growth reflects the strength of the legal state- and tribal-regulated sports betting market and increasing consumer confidence in regulated wagering options.

“March Madness is the highlight of the college basketball season and fans are gearing up for a month of tournament action,” said Bill Miller, President and CEO of the American Gaming Association. “Fans continue to engage with legal, state- and tribal-regulated sports betting in record numbers during one of the biggest moments on the sports calendar.”

Sensor Tower data compiled by the AGA shows that prediction market platforms have rapidly increased their presence in sports betting advertising. While digital ad impressions for online sportsbooks declined nearly 14 percent in 2025, impressions tied to prediction market advertising surged dramatically.

With the expansion of prediction market advertising, nearly one in five (15%) digital sports betting ads seen by consumers last year did not comply with state-mandated responsible gaming messages. Kalshi alone became the third largest sports betting advertiser by digital impressions in 2025.