Legal Glossary
Late Payment Penalty
A fee charged when you don't make a required payment by the due date or end of the grace period.
Legal Definition
A late payment penalty (also called a late fee or default interest) is a contractual charge triggered when a required payment is not made by the agreed deadline — or, in contracts with a grace period, by the end of that grace period. Late payment penalties can take several forms: a flat fee per late payment, a percentage of the amount due, an increase in the applicable interest rate (a penalty rate or default rate), or any combination of these. Consumer protection laws in many jurisdictions cap late fees for specific types of contracts, particularly credit cards, mortgages, and residential leases.
In Plain English
A late payment penalty is exactly what it sounds like: you pay extra when you pay late. How much extra — and when the clock starts — depends on your specific contract and your jurisdiction. For credit cards, the CARD Act caps late fees at around $30–$41. For mortgages, a typical late fee is 3–5% of the missed payment. For leases, late fees must often comply with state caps (some states limit them to 5–10% of monthly rent). The serious risk in loan agreements is not just the flat late fee, but the penalty interest rate — some agreements raise your interest rate on all balances when you miss a payment, significantly increasing your total cost of borrowing.
Real-World Example
Kevin has a personal loan with a $1,200 monthly payment due on the 15th and a 10-day grace period. He pays on the 27th — 12 days after the due date, two days past the grace period. His loan agreement specifies a late fee of 5% of the monthly payment, so he's charged $60 in addition to his regular payment. On his credit card, a payment due on March 20th that he pays on March 22nd triggers a late fee of $29 (within the CARD Act limit) and the risk of triggering the penalty APR of 29.99%.