How long do BT normally take to refund any monies due to you when you leave them? I was paying by quarterly direct debit,my last bill was at the end of January. I then got rid of BT and switched to another phone provider at the beginning of March. Am I right in remembering they (BT) bill you for line rental in advance,and therefore they owe me two months money back for line rental,call minder,etc. How long should it take to get this money back?