You can keep it — this is one of the more reassuring rulings for new Muslims, and it's addressed directly in the Quran itself. In the verse prohibiting riba (interest), Allah specifically says that whoever received the warning and stops is allowed to keep what has already passed, with the matter left to Him, meaning past interest earned before you understood or accepted the prohibition is not something you need to pay back, give away, or feel guilty over. What matters going forward is intention and effort: close or transition away from interest-bearing accounts where practical, look into halal banking or investment alternatives as they become accessible to you, and avoid knowingly taking on new interest-based debt or income. If untangling every financial account overnight isn't realistic, that's okay — do it in reasonable, deliberate steps rather than panicking over your existing bank balance. This area trips up a lot of converts with unnecessary guilt, so let this be one thing you can genuinely exhale about while you focus your energy on prayer, learning, and community.
Q&A · New Muslim
I have savings that include interest from before I became Muslim — is that money halal to keep?
References
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.