Small Claims Demand Letter Interest Calculator

Add legitimacy to your demand letter or small claims filing by calculating the prejudgment interest accrued on an unpaid amount using a simple or annual interest rate.

Interest Owed
Original Amount Owed
Interest Accrued
Total Amount Demanded

About this calculator

Calculate prejudgment interest owed on an unpaid debt or damages amount for inclusion in a demand letter or small claims filing.

Frequently Asked Questions

What interest rate should I use?

Most states set a statutory prejudgment interest rate (often 6-10% annually) that applies when a contract doesn't specify one; check your state's small claims rules.

Is this legal advice?

No, this tool provides a general estimate only. Consult your local small claims court rules or an attorney for exact requirements.

Does interest compound?

This calculator uses simple daily interest, which is the most common method used for prejudgment interest calculations in small claims contexts.