What is the ruling on taking a loan from an institution that requires a payment to be deducted from the salary and reimbursed at the end of service, in addition to paying stamp fees?

Scholars agree that any loan that brings a benefit to the lender is usury (riba), and it is forbidden without dispute if it is stipulated in the contract. If it is not stipulated, it is permissible according to the majority of jurists. Accordingly, it is not permissible for the institution to stipulate a sum of money (50 dinars) upon the employee, to be returned at the end of his service, because this falls under the category of stipulating a loan within a loan. However, if the transaction requires a postage stamp from which the institution derives no benefit, there is no harm in that.