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Debt + Interest Calculator

Calculate the total amount you're owed including statutory interest. The standard rate in NSW is 9% per annum — adjust for your state below.

NSW default: 9% p.a. Check your state's Uniform Civil Procedure Rules for the applicable rate.

How interest is calculated

Statutory interest in Australia is calculated using simple interest: Principal × Rate × (Days Overdue ÷ 365). The standard rate in NSW is 9% per annum under the Civil Procedure Act 2005 (NSW). Other states may differ.

Interest typically runs from the date payment was due (or the date of the debt) to the date of judgment or payment. Including it in your letter of demand signals you know your rights.

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