UK players used to deposit at casinos via phone bills, often paying around £30...

https://magic-wiki.win/index.php/How_Do_I_Know_If_a_Casino_Is_UK-Licensed_When_Checking_Payment_Methods%3F

UK players used to deposit at casinos via phone bills, often paying around £30 per transaction. Now, Faster Payments and mobile methods let them add as little as £10 instantly