Illinois Rent Late Fee Rules

No Illinois statute sets a maximum or percentage limit on residential rent late fees statewide, and the Rent Control Preemption Act does not address fees. A late fee is enforceable only if it is written into the lease; if the lease is silent, no late fee may be charged. Because excessive charges can be struck down as an unenforceable penalty under contract law, a late fee should reflect a reasonable estimate of the landlord's loss. Chicago and Cook County are separate, stricter regimes: the Chicago RLTO limits late fees to $10 per month for rent up to $500, plus 5% of any amount above $500. There is no statewide grace period.

No specific statutory penalty statewide. A late fee not stated in the lease is unenforceable, and a fee a court finds punitive rather than a reasonable damages estimate may be reduced or voided. Under the Chicago RLTO, charging an above-cap fee can expose the landlord to ordinance remedies.