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Legal betting at the ongoing NCAA basketball tournaments is projected to reach $3.3 billion, a figure that underscores the market’s rapid growth.
According to data released by the American Gaming Association on March 13, that figure has jumped 54% in just three years. The trade group attributed the growth to the expansion of legal sports betting under state and tribal regulations, along with increased consumer trust in licensed options.
The March Madness tournaments, which span more than 100 games in three weeks, are among the largest wagering events on the US sports calendar. They provide a major opportunity for operators to attract customers and allow regulators to test whether the legal market is keeping pace with new forms of competition.
Analyzing the $3.3 billion tournament handle
The $3.3 billion projection reflects a larger pattern in US sports betting. Legal wagering is no longer a novelty in states where it has been established for several years; it has become a routine part of major sporting events, especially those with expansive brackets, constant television coverage, and heavy fan engagement.
The AGA said the steady rise in activity reflects confidence in regulated markets. The group’s broader argument goes beyond raw volume, making the case that growth is strongest where consumers see legal products as reliable and where the rules are clear. In that sense, the March estimate is not just a tournament headline—it is a measure of how deeply legal betting has entered mainstream US sports culture.
The rapid rise of prediction markets advertising
The more striking part of the report may be its findings on advertising. According to Sensor Tower data compiled by the AGA, digital ad impressions for online sportsbooks fell by nearly 14% in 2025.
However, prediction market advertising moved in the opposite direction, expanding sharply and allowing those operators to gain a larger share of the US consumer market.
The report found that almost 15% of digital sports betting ads viewed by consumers failed to include responsible gaming messages. Under existing regulations, this is a direct violation of state law—a pattern that grew more noticeable in the early months of 2026.
In the first two months of this year, prediction market operators accounted for 43% of all digital sports betting ads in the US, yet none of those ads included required responsible gaming messaging.
Kalshi stood out most clearly in the ad race. The company ranked third among sports betting advertisers by digital impressions in 2025. In the opening months of 2026, it moved into first place. The report says US consumers were exposed to Kalshi advertising about 5.2 billion times this year, compared with 2.9 billion impressions for FanDuel, the next-highest sportsbook advertiser.
Why traditional sportsbook ad spend is cooling
While prediction markets pushed further into digital channels, overall sportsbook advertising continued to decline.
The AGA said total spending on sports betting ads fell 5% year over year. Ad volume across all channels slipped 1%, and total industry volume is now 27% below its 2021 peak. Television saw an even sharper decline, with sports betting TV ad volume dropping 9% from the prior year—a 50% total fall since 2021.
Those figures run counter to the perception that sports betting ads are flooding every screen. The study found that betting still accounts for a small share of overall television advertising:
- TV Ad Spending (2025): Sports betting accounted for 0.9%, compared with 1.5% for alcohol.
- Ad Volume: Sports betting made up 0.3%, half the alcohol industry’s share and far below pharmaceuticals at 13.9%.
- Frequency: For every sports betting commercial aired in 2025, viewers saw 39 pharmaceutical ads.
The growing need for regulatory compliance
The AGA maintains that legal access alone is not enough to keep bettors confident. The group’s position is that if businesses accept sports bets or market sports-related wagering products, they must comply with existing compliance and consumer protection standards.
With March Madness underway, the $3.3 billion handle will draw headlines, but the larger story remains a shift in the landscape: betting is rising, sportsbook ad spending is falling, and prediction markets are claiming a growing share of public attention.
