Late fee calculator
Work out what an overdue invoice has accrued under your contract terms, and what the total owed now comes to.
Estimate only. Figures update as you type. Not tax advice — see the note at the bottom of this page.
Late fees only work if the contract says so
You generally cannot invoice a late fee that was never agreed. The term belongs in the contract or on the original invoice, stating the rate and when it begins. Adding a fee after the fact tends to produce an argument rather than a payment.
There are legal limits
Some jurisdictions cap the interest rate a business can charge on overdue accounts, and rates above the cap can be unenforceable. A rate around 1 to 1.5% per month is widely used partly because it sits comfortably below most limits, but the limits vary by state and country and are worth checking before writing a number into your contract.
The fee is leverage, not income
Freelancers who get paid on time rarely credit the late fee itself. What changes behaviour is the invoice arriving promptly, the terms being stated plainly, and a follow-up landing the day payment becomes overdue. The fee gives that follow-up something to point at.
Deciding whether to charge it
A good long-term client who is late once is usually worth more than the fee. A client who is repeatedly late is telling you something about how they'll behave on the next project. Waiving the fee is a choice worth making deliberately rather than by default.
Common questions
What is a standard late fee?
Around 1% to 1.5% per month is common in freelance and small business contracts, which works out to roughly 12% to 18% annually.
Can I charge a late fee if it isn't in my contract?
Usually not enforceably. The term generally needs to be agreed in advance, which is why it belongs in the contract and on the invoice.
Does interest compound?
This calculator uses simple interest, which is the common approach in short commercial terms. Compounding requires specific contract language and may face tighter legal limits.