Invoice Late Fee Calculator
Calculate the late fee owed on an overdue invoice, using a monthly or annual interest rate and the days past due.
Late fee owed
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Total now due —
Effective annual rate —
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 rateFrequently Asked Questions
How do I calculate a late payment fee?
Multiply the overdue amount by your stated rate and the time elapsed: at 1.5% per month, a $5,000 invoice that's 45 days late (1.5 months) owes about $112.50 in late fees, on top of the original amount.
What is a typical late fee rate for invoices?
1–2% per month (12–24% annualized) is common for small businesses; some jurisdictions cap allowable rates, and your late fee terms must be disclosed on the original invoice or contract to be enforceable.
Is charging interest on overdue invoices legal?
Generally yes if disclosed upfront in your terms, though rules and maximum allowable rates vary by jurisdiction — check local commercial law or consult a professional before enforcing late fees.