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• Free tool

Invoice late-fee calculator.

An invoice is overdue and you stated a late fee. Enter the numbers below to see the fee and the new total — pro-rated by day so it's fair and defensible.

Late fee
$0
Total now owed$0
Fee per day$0
Effective annual rate0%

How the late fee is calculated

This uses the standard pro-rated method: fee = amount × (monthly rate ÷ 100) × (days overdue ÷ 30). Charging by the day (rather than a full month the moment it's a day late) is the fairer, more enforceable approach.

1.5% per month (about 18% per year) is the most common freelancer late fee — but some states and countries cap interest on overdue invoices, so check your local rules and put the exact terms in your contract before you bill.

Is a late fee legally enforceable?

Generally yes, if the client agreed to it in writing before the work — which is why it belongs in your contract and on the invoice. Some jurisdictions cap the rate; confirm what applies to you.

What's a reasonable late fee?

1–2% per month is typical and widely accepted. The goal is less the extra revenue and more signalling that the due date is real.

Let the fee apply itself.

GigPaper states your terms on every invoice and nudges overdue ones automatically — so you don't have to be the bad guy. 30 days free.

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