Late fee

There is no single nationwide maximum late fee that every U.S. landlord can charge. The allowed amount may be capped by state or local law, limited by a reasonableness standard, controlled by the lease, or prohibited until a required grace period has passed. The first step is the law for the property’s location—not a generic percentage found online.

A late fee is an extra charge tied to rent that was not paid by the applicable deadline. Before assessing one, confirm that the lease clearly states the fee, the due date, and any grace period; then check current state and local requirements for the amount, timing, notice, and recurring daily charges. The calculator can do the arithmetic, but it cannot decide what is lawful.

Rules can define the cap in different ways: a percentage of monthly rent, a percentage of the unpaid balance, a reasonableness test, a flat amount, or a combination. They can also delay when a fee may be charged or impose separate requirements for written lease language. A result that is valid in one state or city may be unlawful at an otherwise identical property elsewhere.

Operationally, keep the original rent charge, the payment timestamp, the applicable grace-period calculation, the lease clause, the law-review date, and any approved waiver or correction together. A late-fee ledger entry should be explainable without relying on a staff member’s memory, and exceptions should be applied consistently and reviewed for fair-housing or consumer-law risk.