Sports betting

What it is

Sports betting is the practice of placing a wager on the outcome of a sporting event, with licensed operators accepting bets, setting odds, and retaining a margin (the "vig" or overround) on every market. The market spans traditional fixed-odds wagers on match winners, spread betting, and in-play betting on granular outcomes such as the next goal-scorer or the result of a single at-bat. As of 2025, online and mobile platforms account for roughly 75 percent of global volume. The principal legal operators are Flutter Entertainment (owner of FanDuel, Paddy Power, and Betfair), DraftKings, BetMGM (a joint venture between MGM Resorts and Entain), Caesars Sportsbook, and Bet365. Illegal markets, run primarily by Asian criminal syndicates, are estimated to dwarf licensed markets by a multiple of ten or more by total handle.

History

Organised sports betting has deep roots in Britain, where bookmaking at horse-racing venues dates to the 18th century. The UK Gambling Act 2005 consolidated the regulatory framework and gave the UK Gambling Commission statutory oversight of the industry.

In the United States, Congress passed the Professional and Amateur Sports Protection Act (PASPA) in 1992, restricting legal sports wagering to Nevada, with limited legacy exemptions for Oregon, Montana, and Delaware. All other states were barred from authorising sportsbooks.

New Jersey challenged PASPA starting in 2011. The US Supreme Court ruled 6-to-3 on 14 May 2018 that PASPA violated the anti-commandeering doctrine of the Tenth Amendment because it "unequivocally dictates what a state legislature may and may not do." Within weeks of the ruling, Delaware and New Jersey opened licensed sportsbooks. Within six years, 38 states and the District of Columbia had enacted sports-betting legislation.

Current state

US sports-betting revenue reached a record US$16.96 billion in 2025, up 22.6 percent on 2024, on a total handle of US$166.94 billion, according to the American Gaming Association's 2026 report. New York, Illinois, and New Jersey are the top three US markets by revenue. Legal sports betting contributed approximately US$18 billion in state and local tax revenue in 2025.

Globally, the market exceeded US$110 billion in revenue in 2025, with Europe accounting for roughly 44 percent of global share. In Great Britain, the UK Gambling Commission reported a total gross gambling yield of £16.8 billion in the year to March 2025, up 7.3 percent year on year. Football betting generated £1.3 billion of that yield; horse-racing betting generated £766.7 million. Brick-and-mortar betting shops in Great Britain have fallen for eleven consecutive reporting periods, to 5,825 locations, as volume migrates to mobile apps.

Relationships

US sports leagues that once lobbied against legalisation now hold official betting-partner agreements and data-licensing deals with operators, converting game statistics into a licensed commercial product. The structural overlap with prediction markets is growing: Kalshi and similar exchanges offer event contracts on sports outcomes, competing with the traditional bookmaker's fixed-odds model and inviting regulatory scrutiny over whether event contracts constitute gambling under US law.

Match-fixing is the primary integrity threat. Illegal syndicates place large wagers on manipulated outcomes, most commonly in football, cricket, and tennis, using unregulated markets that accept large anonymous stakes. INTERPOL's Match-Fixing Task Force coordinates more than 100 law-enforcement units across 150 countries. Illegal betting remains the preferred vehicle for fixers precisely because it offers no identity verification and no market limits. For the broader integrity picture see Sport integrity: betting, doping, match-fixing and corruption under global law.

What to watch

• Whether the US Congress passes a federal sports-betting framework, resolving conflicts between state-by-state regulation, tribal gaming compacts, and the emerging prediction-market sector.
• Responsible-gambling enforcement: the UK Gambling Commission introduced a £5-per-spin maximum stake on online slots in September 2024, and US states are tightening advertising rules, with New York banning sportsbook sign-up bonuses pitched at problem gamblers.
• The regulatory boundary between licensed sports betting and exchange-traded prediction markets, with US courts and the Commodity Futures Trading Commission determining whether Kalshi's sports contracts sit inside or outside gambling law (see 칼시, 5개월 만에 기업가치 220억 달러로 두 배… 예측시장 주류화 속 400억 달러 겨냥).