110 ILCS 992/5-15: Fees.

(a) Unless otherwise provided by federal law, a servicer may only charge late fees that are reasonable and proportional to the cost it incurs related to a late payment.

(b) Unless otherwise provided by federal law, a servicer shall not charge a borrower or cosigner any fee to modify, defer, forbear, renew, extend, or amend the borrower's or cosigner's loan.