UK online casinos operate under strict rules set by the UK Gambling Commission....
https://high-wiki.win/index.php/What_Are_the_Three_Competitive_Tiers_in_UK_Online_Casinos%3F
UK online casinos operate under strict rules set by the UK Gambling Commission. This means games must offer a fair return to players, like an average 96% RTP. You’ll also find faster payments options, with some sites claiming withdrawals within 60 seconds