CSA Calculator Australia

Under the Child Support (Assessment) Act 1989 administered by Services Australia, child support liability is governed by an objective 8-step formula. Rather than assessing only the non-resident parent, Australia calculates the combined financial responsibility of both parents.

The system guarantees that both parents retain a protected self-support amount ($28,784, adjusted annually based on Average Weekly Earnings) before any child support obligation is calculated.

Under Australian law, contact does not reduce child support pound-for-pound; instead, overnight care translates into a statutory Cost Percentage:

• 0 to 51 nights (0% to <14% care): 0% cost percentage (Nil care credit).
• 52 to 127 nights (14% to <35% regular care): 24% cost percentage.
• 128 to 175 nights (35% to <48% shared care): 24% plus 2% for each percentage point over 35%.
• 176 to 189 nights (48% to 52% equal care): 50% cost percentage.

Parents who wish to agree to a private maintenance sum outside the Services Australia formula must enter into a Binding Child Support Agreement (BCSA). Under Section 80C of the Act, a BCSA is only legally valid if both parents have received independent legal advice from separate qualified Australian legal practitioners who sign formal legal certificates.