Invoice Late Fee Calculator

Late fees owed on overdue invoices — monthly or daily penalty rates.

Invoice amount ($):

Late fee rate (%):

Rate applies:

Days overdue:

How to use

Enter invoice amount, late fee rate, and days overdue, then click Calculate.

What late fee is typical?

1-1.5% per month (12-18% APR) is common in the US. Check your contract — the agreed rate governs.

Can I charge a flat fee instead?

Many freelancers use a flat fee (e.g. $25) plus monthly interest. This calculator handles the percentage part.

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