How to use late payment fee calculator
- Enter an outstanding amount and the original due date.
- Choose a payment or evaluation date and grace days.
- Enter a fee rate and select flat, daily simple or 30-day simple calculation.
- Review days overdue and potential fee.
Example
A $1,000 debt, 30 days late, at a user-chosen 12% annual simple rate yields approximately $9.86 (365-day basis).
How the calculation or document works
Simple annual fee = balance × annual rate × chargeable days ÷ 365. A flat fee applies once when overdue. Monthly simple uses 30-day periods.
Frequently asked questions
Is the fee enforceable?
Not automatically. Confirm your contract and local legal limits.
Does this compound interest?
No. Both time-based modes calculate simple, not compounding, charges.
Related tools
Financial, tax and legal results are for educational planning and may not meet the requirements of your jurisdiction. Browser storage is not a backup. Export important records regularly.