Bank Fines Are Illegal
Yes, you read what I wrote. It is illegal for any bank, building society, or credit union to invoice you for any quantity of cash beyond the actual expenses you have incurred them. So states Common Law, Statute, and consumer rights as dictated by the Office of Fair Trading.
So, follow these steps, and with the information gathered, send your bank this letter, and you can kiss your over-the-odds charging woes goodbye, and look forward to a jurisprudent rebate to boot.