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Late Fee Calculator

Calculate flat or percentage late fees, daily or monthly, and the total now due on an overdue invoice.

Enter your figures

Currency
$
%
days

Result

Total now due

$1,030.00

Late fee$30.00
Original invoice$1,000.00
Periods charged2 month(s)

Calculate the late fee on an overdue invoice — a flat charge or a percentage, applied once or accruing daily or monthly — and the new total amount due.

Formula

  • Percentage fee = Invoice × Rate% × periods
  • Flat fee = Fee × periods
  • Total due = Invoice + Late fee

Example

A $1,000 invoice with a 1.5% monthly late fee that is 60 days overdue accrues 2 monthly periods = $30, for a total of $1,030.

Frequently asked questions

Are there legal limits on late fees?

Yes — many regions cap late fees or interest on overdue invoices. Confirm the maximum allowed in your jurisdiction and state the fee in your contract.

Late-fee and interest limits vary by jurisdiction and contract. This tool only computes a fee you define and is not legal advice.