UK online casinos operate under strict rules set by the UK Gambling Commission...

https://www.bookmarking-fox.win/uk-online-casinos-operate-under-strict-rules-set-by-the-uk-gambling-commission

UK online casinos operate under strict rules set by the UK Gambling Commission to ensure fair play and protect players. For example, games typically have a minimum return to player rate of 96%, meaning the house edge is carefully regulated