Every March, millions of Americans do something they almost never do the rest of the year — they bet on college basketball. Whether it’s a $5 office pool or a serious wager at a sportsbook, the scale of March Madness betting is staggering. Just how much money changes hands during the NCAA Tournament? The answer might surprise you.
The Numbers Are Staggering
The American Gaming Association estimates that over $3 billion was wagered legally on the 2025 NCAA Tournament alone. When you add informal bracket pools and illegal betting, total wagering is estimated at around $15 billion over the three weeks of the tournament. That makes March Madness the second biggest sports betting event in the United States — behind only the Super Bowl.
Legal Betting Has Exploded Since 2018
Before 2018, sports betting was illegal in most U.S. states outside of Nevada. That changed when the Supreme Court struck down the federal ban on sports gambling, opening the door for states to legalize it individually. Today more than 35 states allow legal sports betting — and March Madness has become one of the biggest events on the sports betting calendar. If you’re new to sports betting, a good sports betting guide can help you understand the basics before placing your first wager.
Bracket Pools: The Unofficial Economy
Beyond sportsbooks, an enormous amount of money flows through informal bracket pools — the kind run in offices, group chats, and family gatherings. The American Gaming Association estimates that around 68 million Americans fill out at least one March Madness bracket each year, with total bracket pool wagering estimated in the hundreds of millions of dollars. Running a bracket pool with a buy-in? A poker chips set makes collecting and paying out the pot easy and fun.
Where Does the Money Go?
When you place a legal bet through a sportsbook like DraftKings or FanDuel, here’s roughly where your money ends up:
— Winners: The majority is paid out to winning bettors — The “vig” or “juice”: Sportsbooks take a small cut — typically 5–10% — on every bet — State taxes: States tax sportsbook revenue, often 10–50% depending on the state — Operators: The remainder covers operating costs and profit for the sportsbook
How Does March Madness Compare to Other Events?
To put the numbers in perspective, here’s how March Madness stacks up against other major betting events in the U.S.:
— Super Bowl: approximately $23 billion wagered — March Madness: approximately $15 billion over three weeks — NBA Finals: approximately $500 million — Kentucky Derby: approximately $400 million
Final Thoughts
Whether you’re placing a legal bet, joining an office pool, or just watching with friends, March Madness moves an extraordinary amount of money every year. It’s one of the clearest signs that the tournament isn’t just a sporting event — it’s a cultural and economic phenomenon unlike anything else in American sports.