Invoice Late Fee Calculator
Use this invoice late fee calculator to calculate a late fee or interest on an overdue invoice. Enter invoice amount, due date, payment date and fee rate and review estimated late fee and amount due.
Verify your late-fee terms are properly disclosed and compliant with local law before charging.
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How it works
Late fee = invoice amount × daily rate × days overdue, or a flat monthly rateHow to use the Invoice Late Fee Calculator
Start by entering invoice amount, due date, payment date and fee rate. Keep the units consistent and check that each value belongs to the same question.
The result gives estimated late fee and amount due. Contract terms and local law control whether a fee can be charged. Use it as a guide and check any instructions, rules or professional advice that apply.