Family Law Interest Calculator
The calculator calculaator interest in accourdance with the Family Law Rules 2004. The rate of interest is the RBA cash Rate plus 6%. The Family Law Rules in respect of interest changed on 1 July 2010. This calculator applies the correct rate of interest from 1 July 2020.
Help with the 3 key inputs above
Date From: The date from which interest accrues (Calculator starts from 1 July 2010)
Amount: This is the Australian dollar value amount of the judgment which is subject to the interest calculation.
How the Family Law Interest Calculator works:
Interest is calculated using the following methodology contained in the Family Law Rules 2004 Rule 17.03 Rate of Interest being:
- in respect of the period 29 March 2004 to 30 June 2010. This calculator does not use the Family Law rate prior to 1 July 2010.
- from 1 July 2010, in respect of the period from 1 January to 30 June in any year – the rate that is 6% above the cash rate last published by the Reserve Bank of Australia before that period commenced, and
- from 1 July 2010, in respect of the period from 1 July to 31 December in any year – the rate that is 6% above the cash rate last published by the Reserve Bank of Australia before that period commenced
Family Law interest is calculated by reference to the Reserve Bank of Australia Cash Rate plus 6% calculated in six month periods. Interest is calculated on a simple basis (not compounding).
The Family Law Interest Calculator has been updated to include the RBA Cash Rate up to 30 June 20254. Next Update: 1 July 2025