Many Lloyds TSB customers are being hit with charges of up to £200 a month if they go into the red - while Muslims who use the bank are only being charged £15.
The part-nationalised bank has been accused of religious discrimination over the disparity between overdraft charges on its standard current account and its Islamic account.
The Islamic account was set up by the high street bank to attract Muslim customers by allowing them to keep faithful to their religion.
Sharia law does not permit the payment of interest so the ‘typical’ Islamic account at Lloyds TSB has been set up without an overdraft facility.
If a Muslim customer who has insufficient funds in the account tries to make a payment, it is blocked and a ‘return item fee’ is charged.
However, on some Islamic accounts such a payment is authorised and an ‘unplanned overdraft fee’ of £15 is then levied.
The bank says this is a management fee, not a payment of interest, so does not contradict Sharia law.
Meanwhile, customers with standard current accounts who go into the red by at least £100 without authorisation are hit with an ‘unplanned overdraft fee’ of £20 a day for a maximum of ten days. This could mean a customer has to pay £200 in one month.
The Islamic account is available to all customers at Lloyds TSB. In theory, anyone who does not need a permanent overdraft facility could switch to this account to avoid being hit by interest charges for going into the red.
The disparity between the two accounts emerged after the bank sent its customers a booklet this month explaining its charges.
Graham Milne, a customer and chartered accountant from Norham, Northumberland, said difference in fees was tantamount to ‘religious discrimination’.
He added: ‘This means that all the non-Islamic account holders are subsidising those with such an account. It strikes me as something which is bordering on illegal.
‘One cannot help feeling the organisation is bending over backwards to help Muslims to the detriment of everybody else.
‘The man in the street would say this is a form of theft. Whether you call it a management fee or an interest fee, it makes no odds because they mean the same thing.’
In the past few years, millions of customers at all the major high street banks have demanded the return of money which has been taken from their account in various forms of bank charges.
Many got their money, or the majority of it, back. A test case - designed to rule if such charges are illegal - is going through the House of Lords.
Until it is resolved, the subject continues to remain hotly contested.
A Lloyds TSB spokesman said: ‘The Islamic current account is for customers who cannot receive credit or debit interest due to their religious beliefs.
‘All of our Islamic accounts comply with Islamic law and are available to anyone regardless of background or faith.
‘These accounts are structured differently to our traditional accounts and are designed to help prevent a customer slipping into the red. A comparison with the overdraft charging structure on other accounts is meaningless.’
Earlier this month, it emerged that losses at Lloyds had escalated to £13.4billion - largely due to the reckless lending of Halifax Bank of Scotland, which it bought for £9.6billion in January.
The disastrous merger led to a £17billion taxpayer bail-out. The newly-formed Lloyds Banking Group is 43 per cent owned by the taxpayer.