We are in the process of refunding customers who overpaid their safety deposit box fees, and some of the refund checks are for less than $1. Does Illinois law address whether there is a de minimis amount that does not have to be refunded?

No, we are not aware of any Illinois law that would allow you to forgo refunding overpaid safety deposit box fees, even in very small amounts.

We recommend reviewing the terms of your safety deposit box account agreements to determine whether they entitle you to retain overpaid fees in small amounts. If your agreements do not expressly allow you to retain overpaid fees, we believe you should refund all overpayments, no matter how small.