Calculators / Late fee
Late Fee Calculator
The late fee on an overdue invoice, from the amount, your monthly rate or flat fee and the days past due.
How it's calculated
Late fee = invoice amount × monthly rate × (days past due ÷ 30), plus any flat fee.
A late fee only holds up if the client agreed to it before the work: put it in your estimate and in the invoice's payment terms (for example, “1.5% per month on balances over 30 days”). Many states cap the rate you can charge, so check the rules where you work before you set it. A friendly reminder a few days before the due date usually works better than the fee itself.
Frequently asked questions
What is a typical late fee?
Many businesses use 1% to 1.5% per month or a small flat fee. The legal maximum depends on your state or country, so check it before you put a rate in your terms.
Can I add a late fee if it wasn't in the invoice?
It's risky. The client has to agree to it in advance, so state it in the estimate and in the payment terms of every invoice.