The UK Gambling Commission’s latest Illegal Gambling Index estimates that 4% of people who gambled online in Great Britain during the year to April 2026 engaged with illegal gambling websites. The estimate combines 2.5% who reported qualifying behaviour in the previous four weeks and a further 1.5% who reported it during the previous 12 months but not the latest four weeks.
Across the whole population, including people who did not gamble, 0.6% showed qualifying engagement in the previous four weeks and another 0.4% in the previous 12 months but not the previous four weeks. A further 4.6% showed limited indications that were not strong enough to classify them as users.
How the index works
The index combines seven self-reported behavioural indicators, including use of sites known not to be on Gamstop, access through a VPN, gambling with cryptocurrency and cancelling withdrawals before funds reach a bank or wallet. The Commission says the measure is designed to capture behaviour that consumers may not recognise as use of an illegal site.
The regulator cautions that the figures are estimates and do not provide a definitive measure of the illegal market’s size. It said the indicators do not currently show sustained or substantial growth. The new survey-based index is a separate evidence stream from the Commission’s earlier open-banking analysis.