How much will Americans bet on March Madness this year? Hint: It's more than the Super Bowl

March Madness remains America’s biggest betting event.

An estimated $3.1 billion is expected to be legally wagered on this year’s men’s and women’s NCAA tournaments, the American Gaming Association announced Thursday. That’s a 12% year-over-year increase and more than double the $1.39 billion the AGA estimated would be bet on this year’s Super Bowl.

The volume of bets reflects the expansion of legal wagering across America since the Supreme Court struck down a federal ban in 2018 and gave states permission to decide for themselves. Thirty-eight states and the District of Columbia have legalized some form of sports betting, enabling citizens to place wagers at online or brick-and-mortar sportsbooks.

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“March Madness is one of the most exciting times in American sports, with fans fired up for both the men’s and women’s NCAA tournaments,” Joe Maloney, the AGA’s senior vice president of strategic communications, said in a press release announcing the estimate. “As legal wagering expands across the U.S., more fans than ever have the opportunity to bet legally and responsibly.”

The AGA analyzes revenue reports from state gambling regulators and other trends to develop a legal wager estimate for March Madness and other sporting events. Last year, the group estimated that a total of $2.72 billion would be legally wagered on the men’s and women’s NCAA tournaments.

Estimates from the AGA do not include money wagered offshore or in office bracket pools.

Brackets for the men’s and women’s NCAA tournaments will be unveiled Sunday. Auburn (+325) and Duke (+375) are currently BetMGM’s favorites to win the men’s NCAA championship. South Carolina (+275) and UConn (+280) are BetMGM’s betting favorites on the women’s side.