The idea behind the site is simple: most accounting teams end up with a maze of spreadsheets for late‑payment interest, and they constantly have to chase down current rates. This tool aims to collect the key resources in one place and make the calculation process consistent and easier to explain.
The page is created and maintained by C. Sonsteby. Contact information is provided below.
What it does
- Calculates interest on a principal amount between a due date and an end date (often today).
- Splits the calculation into periods when the applicable statutory rate changes.
- Adds fixed compensation amounts where the relevant rules provide for it (shown separately).
- Lets you adjust calculation assumptions (for example, day-count convention and whether interest starts on the due date inclusive).
What it does not do
- It does not determine whether you are legally entitled to interest in your specific case. Entitlement can depend on the contract terms, the governing law, the parties (e.g., business vs consumer), and any applicable statutory exceptions.
- It does not provide debt collection services or legal advice.
Sources and accuracy
Where possible, the tool uses publicly available official sources (central bank rates and statutory references). The sources are linked in the guides for each regime. You should always verify the applicable rules against your contract and the governing law.
Privacy
Calculations are performed in your browser. We do not store the amounts, dates, or other inputs you enter into the calculator.
Our server may keep standard access logs for security and reliability. If you have any questions concerning privacy and personal data, please contact us.
Privacy Notice and Cookies Policy
Comments, ideas or suggestions?
Email: contact@latepaymentinterest.com
This page is prepared in Norwegian and English. Translations into other languages are AI‑assisted.