NEW YORK - Unregulated offshore sports betting sites have twice the scale of regulated books in the U.S., a study released this week finds.
The survey from research firm Blask and gaming event purveyor Next.Io found that despite the growth of legal betting, offshore sites still have twice the scope of the regulated market. Using data that incorporates search interest, engagement and other trends, the survey estimates unregulated books have twice the financial value of legal books.
The survey can’t equate a dollar-for-dollar comparison, but it gives another data point on the illegal market’s size. With the regulated market generating just under $150 billion in handle in 2024, the study projects the unregulated market could be around $300 billion.
These results come despite the massive expansion of legal sports betting since the Supreme Court struck down the federal single-game wagering ban outside Nevada in May 2018, allowing states to legalize betting within their respective borders. It would also translate to a far greater scope to the illegal sports betting market, which the American Gaming Association estimated was around $64 billion in 2022.
Study details
The analysis found that five of the top ten most popular brands nationwide were offshore operators.
This data accounts for California and Texas, the nation’s two most populated states, which combined have more than 65 million residents. Neither state has legal sports betting.
In legal states, offshore books still have a significant market share.
Hard Rock Sportsbook, the only legal book in Florida, only has 20% market share in the state: 80% of sports bets placed in FL are with offshore books, per research cited by Next Io's Pierre Lindh at a company conference today
— Ryan Butler (@ButlerBets) March 12, 2025
Florida, the most populated state with a legal book, offshore brands make up roughly 80% of the size of the market, per the study. The lone legal book, Hard Rock, has smaller bettor interest than Bovada, the number one book by value in both Florida and nationwide, per the study’s findings.
Even in many of the nation’s most populated competitive betting states, offshore books have significant interest. At least one offshore operator is among the top five most-popular brands in New York, Ohio, Massachusetts and Illinois.
Offshore market participation is less substantial in the four fully competitive legal online casino gaming states. No offshore book was among the top five in interest in the quartet of New Jersey, Pennsylvania, Michigan and West Virginia.
Combating offshore books
Thirty-one states, Washington DC and Puerto Rico have approved legal online sports betting, representing about half of the U.S. population. Advocates have pushed regulation as a way to capture the offshore market, but the study reaffirms the illegal market’s continued grip on U.S. bettors.
Along with legalization, a growing number of state regulatory bodies have pushed back against offshore operators with cease-and-desist letters. Bovada has stopped accepting bets in more than a half-dozen states including New York, the nation’s largest competitive legal sports betting state by handle. The study found Bovada was not among the five most popular books in New York, but it remains a major player in Ohio, despite it leaving the Buckeye State in August 2024.
Legal sports betting stakeholders have had less success pushing federal regulatory crackdowns on offshore operators, which they argue is essential to stop books emanating from other countries from accepting bets from U.S. players. The Biden Administration took no meaningful action and the current Trump Administration has also shown little interest in a crackdown.
State regulators have targeted individual operators but don’t have the capability or resources to prevent all offshore operators. The study found nationwide nearly 300 different offshore brands accept bets from U.S. players.
