Question: Virtuous Shaikh! Some banks give gifts to the one who places/deposits money in his account with the bank for protection only, not for usury nor any other reason. So is it allowed for him to use it [the gift] or not?
Answer: ” You know, may Allah bless you, that placing dirhams in the bank is not a deposit. It is only a loan. The people are mistaken in calling it a deposit. This is because if you give the bank dirhams, does it keep them safe in their [original] form until you come [for it] or does it enter it into a fund and use it? It places it in a fund and uses it. Therefore, it is a loan. If it is a loan then it is not allowed for the one giving the loan to take something from the one who is given the loan. Not a gift or other than it except if he takes [back] what he had loaned. Then there is no harm if he is given a gift after the loan is fulfilled to him. There is no harm upon him to fulfill [it to him]. Likewise, if the bank is giving gifts to the one who places/deposits money with them which are general gifts for everyone. For example, some banks give calendars. [Then] there is no harm in accepting it because these calendars are given to one who loans them money and the one who does not loan them money”
[Liqaa Bab al-Maftooh no. 196]
Faisal Ibn Abdul Qaadir Ibn Hassan