Late fee and interest calculator
Calculate how much to pay on an overdue bill, rent or invoice: a late fee plus daily interest prorated by the days late.
How to useLate payment fee and interest calculator
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Late fee and interest calculator: what it is for
Enter the amount, the due date and the payment date. The calculator adds the late fee and the daily prorated interest and shows the total to pay, with each part of the calculation listed separately.
The rates can be changed to match your contract.
How to use
- Enter the original amount.
- Choose the due date and the payment date.
- Check the fee, interest and total.
When to use it
- Paying an overdue bill.
- Charging late rent or tuition.
- Checking the amount a company charged you.
Frequently asked questions
How much can a late fee be?
It depends on the contract and local law. Many places cap late fees on consumer debts or rent, often at a percentage of the amount due. Check your contract or lease and the rules where you live.
How is late interest calculated?
A common approach is a monthly rate charged in proportion to the days late (simple interest). At 1% per month and 15 days late, for example, interest comes to 0.5% of the amount.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.