One in 25 online gamblers used illegal sites, Gambling Commission’s new index finds

How the index works

Asking people outright whether they use illegal sites does not work well, because many players do not realise a site is unlicensed. So the Commission, working with research agency Yonder, built the index from seven warning signs in the Gambling Survey for Great Britain. They include playing on a site that is not part of GAMSTOP, signing up without proof of age or identity, cancelling a withdrawal, using a VPN to reach a site not available in Britain, and gambling with cryptocurrency, NFTs or money taken straight from a credit card.

People showing enough of those signs are counted as illegal-site users. On that basis, 2.5% of online gamblers (excluding people who only play National Lottery games) used an illegal site in the four weeks before the survey and a further 1.5% earlier in the year, giving the headline figure of about one in 25. A further 4.6% of all adults showed some signs, but not enough to be counted.

Who is using illegal sites

Use was higher among men and younger adults, especially those aged 18 to 24. Among people counted as illegal-site users, 58% had used a non-GAMSTOP site and 57% had cancelled a withdrawal before receiving the money, a classic tactic on unlicensed casinos that tempts players to keep spinning.

A separate Commission study published on 28 October analysed 157.2 million anonymised Open Banking transactions from about 38,000 people. It found that people using illegal gambling websites were more than seven times as likely to show signs of problem gambling as those using licensed sites, and that most illegal-site users also gamble with licensed operators. The Commission was clear that the data does not prove illegal sites cause the harm.

How many illegal sites are out there

Alongside the index, the Commission’s November dashboard found 586 illegal gambling websites reachable from Great Britain in September 2026, and that 4% of gambling-related Google search results led to an illegal site. Between July and September it took action against 311 illegal websites, 38% more than in the previous quarter. We cover the enforcement figures in our report on the record URL referrals.

This is the first year of data, so the Commission cannot yet say whether illegal use is rising or falling, and some industry voices have questioned the survey method. Expect the index to become the benchmark in future debates about stake limits, affordability checks and tax.

How to make sure your slot site is licensed

• Check the licence. A UK-licensed casino shows its Gambling Commission account number in the footer. Search it on the Commission’s public register.
• Be wary of “not on GAMSTOP”. Any site advertising that it is outside GAMSTOP is, by definition, not licensed for British players.
• Watch the stake. Licensed slots cap spins at £5 (£2 if you are 18 to 24). A site letting you stake £50 a spin is not UK-licensed.
• Use our checks. Every slot site we feature is run by a UKGC licence holder; see best slot sites UK and UK slot rules.