Fatwa
I had some bank interest which I almost separated from my business account.
Is it allowed to give this interest to my son in law?
Answer
Wa’alaykum as Salam wa rahmatullahi wa barakatuhu,
In principle, a person has to return the interest money back to its owner. However, if that is not possible or feasible (as in the case with a bank), then the interest money should be given to the poor and needy without the intention of any reward.
If your son in law is so poor that he is legible for Zakah, then it will be permissible to give the interest to him. (Contemporary Fatawaa: pg. 242, Idara-e-Islamiat)
References
ويردونها على أربابها إن عرفوهم، وإلا تصدقوا بها؛ لأن سبيل الكسب الخبيث التصدق إذا تعذر الرد على صاحبه (تبيين الحقائق – 6/ 27)
والحاصل أنه إن علم أرباب الأموال وجب رده عليهم، وإلا فإن علم عين الحرام لا يحل له ويتصدق به بنية صاحبه (رد المحتار- 5/ 99)