Is it permissible to defer a bank installment due in exchange for additional fees?

A loan is a benevolent contract, and it is impermissible to stipulate an interest on it, whether at the beginning of the contract or upon delayed payment. Increasing money in exchange for deferring the term is precisely the usury of the pre-Islamic era, which scholars have unanimously agreed to be forbidden. Any loan that stipulates an increase is unlawful. Thus, the deferral fees taken by the bank, which vary with the debt amount or are substantial fees, constitute usury. However, very modest fees, such as the cost of paperwork, are permissible if they do not vary with the amount of the loan. When a debtor is unable to pay, the obligation is to grant him respite until he is able to pay, not to increase the price on him.