Illegal Gambling in the UK Climbs to 9% as Vulnerable Players Targeted

The size of Britain’s illegal gambling sector has escalated sharply, with Yield Sec data showing it captured 9% of the market in the first half of 2025, equivalent to £379 million in revenue. Yield Sec chief executive Ismail Vali shared the findings at a Peers for Gambling Reform event, noting that the market share has multiplied since 2020, when it was just 0.43%.

According to the report, the black market now consists of hundreds of unlicensed operators backed by thousands of affiliates. Yield Sec estimates around 700 operators promoted by more than 1,600 affiliates, compared with the regulated market’s 2,000 licensed brands and 7,000 affiliates.

The analysis concluded that the surge is not linked to mainstream bettors shifting away from licensed sites but to criminals exploiting self-excluded gamblers and underage users. Vali described it as an expansion built entirely on “exploitation of vulnerable groups.”

Central to the findings is the rise of so-called “not on Gamstop” operators, which specifically advertise to players who have signed up to the national self-exclusion scheme. Vali explained: “So of 100% of stuff that you see promoting illegal gambling, 84% is not-on-Gamstop related. Not-on-Gamstop was a problem that started in 2020, we’ve said something about it every single year. And every single year, this thing doubles the size of the UK’s illegal gambling sector. This is an area where that phenomenon simply has not been killed.”

Gamstop’s database contains more than 532,000 registered users. Yield Sec projected that with a recidivism rate of 25%, these players alone could generate £426 million in losses for unlicensed operators. When factoring in underage gamblers, the potential total swells to nearly £583 million.

Vali underscored how illegal businesses deliberately pursue these groups: “You go after the people who have no choice, children and self-excludes.”

The report was commissioned by the Campaign for Fairer Gambling (CFG). Its founder Derek Webb argued that tax reform is needed, stating: “The illegal sector does not compete with established brand names here. It targets the vulnerable underage and self-excluded groups, pushing the most addictive content via ‘casinos not on Gamstop’ marketing.” Webb called on Labour to adopt Gordon Brown’s recent proposal for higher gambling duties, describing it as a chance to “atone for the economic harms caused by electronic gambling.”

Not everyone agrees with the Yield Sec assessment. Paul Leyland of Regulus Partners suggested the illegal market share is closer to 5.3%, compared with Yield Sec’s 9%. He also disputed the scale of underage gambling and argued that “Gamstop is a secondary driver accounting more for search than underlying behaviour.”

Leyland pointed to several structural pressures on licensed operators as reasons for the growth of unlicensed activity. These include the 2017 tax on gaming bonuses, intensified affordability and anti-money laundering checks, and the recent  on online slot stakes. He noted that illegal sites are able to offer untaxed bonuses with looser terms, which appeal to some customers.

Top casinos in United Kingdom

100% up to

£111

+ 77 Free Spins

#Ad.New Customer Offer. T&C’s Apply. 18+.Min deposit £10, wagering 60x for refund bonus, max bet £5 with bonus funds. 100% refund bonus up to £111 + 77 spins on 1st deposit. No max cash out on deposit offers. Eligibility is restricted for suspected abuse. Welcome bonus excluded for players depositing with Ecopayz, Skrill or Neteller. Full T&Cs apply. Begambleaware.org, Gamble Responsibly.

Overall Rating

89

Visit Casino Read Review

up to

£30

New Customer Offer. T&C’s Apply. 18+. #AD. Min deposit £20 (PayPal & PaySafe excluded) Max bonus £30 with 30x wagering (deposit + bonus) on selected games. Max win £2,000.

Overall Rating

85

Visit Casino Read Review

100% up to

£200

New Customer Offer. T&C’s Apply. 18+. #ad. Opt-in Required. Wagering occurs from real balance first. 50x wagering the bonus or any winnings generated from free spins, the contribution may vary per game. Available on selected games only. The wagering requirement is calculated on bonus bets only. The bonus is valid for 30 days from issue. Max conversion: 3 times the bonus amount. Excluded skrill deposits.

Overall Rating

82

Visit Casino Read Review

Between 2022 and 2024, the regulated online gambling market in Britain grew by 19%, while the illegal sector expanded by 345%, according to CFG. Both groups, however, acknowledge that the black market has become more visible since 2018, when its share was minimal.

Vali himself has previously cautioned that sudden tax increases could worsen the situation. In an earlier interview with Hedgeye, he said: “If you start giving them surprises like ‘we are doubling the tax rates’, what do you think will happen? … Because they are not pricing themselves as competitively as they used to, crime comes in.”

Yield Sec also highlighted how online searches and social media have allowed “not on Gamstop” sites to find an audience, though some progress has been made in redirecting such searches toward responsible gambling resources.

The contrasting viewpoints reveal a split over whether regulation or criminal targeting is the main driver of the black market. What remains undisputed is that illegal operators are now responsible for a significant share of the UK’s gambling activity, with vulnerable players bearing the brunt.

Source:

““, fox2now.com, September 3, 2025