Late payment fees are charges imposed by a lender or service provider when a payment is not made by the due date. These fees serve as a penalty for the delay and encourage timely payments. The amount of the fee can vary based on the terms outlined in the agreement or contract. Typically, late payment fees are calculated as a fixed amount or a percentage of the overdue balance. They can apply to various types of accounts, including credit cards, utility bills, and loans. Understanding these fees can help individuals manage their finances and avoid unnecessary costs.