Instant

Free Late Invoice Fee Calculator

Calculate late payment fees and interest on overdue invoices. Add monthly interest and flat fees.

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Late Invoice Fee Calculator

Calculate late payment penalties

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How to Calculate Late Invoice Fees

Enter the invoice amount, the number of days late, your monthly interest rate (typically 1-1.5% per month), and any flat late fee. The calculator shows the accrued interest, total fees, and total amount due.

Frequently Asked Questions

Everything you need to know about this tool.

What is a typical late fee rate?

Most businesses charge 1-1.5% per month (12-18% APR) plus a flat fee of $25-50. Check your contract terms and local regulations.

Is this calculator free?

Yes, completely free with no signup required.

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