What is the ruling on purchasing devices in installments through bank cards if the bank adds "administrative fees" to the monthly installment, and these fees are not related to late payment, but it is not clear whether they are related to the value of the amount?

It is permissible for the bank to charge administrative fees on installment purchases if these fees are equivalent to the actual cost of the services related to lending, such as employee salaries. These fees are not considered forbidden usury (riba).

However, if the administrative fees are linked to the loan amount or its duration, they are considered forbidden usurious interest, and the bank is not allowed to charge them, nor should the customer proceed with the purchase in such a case.