The assessment formula

The child support assessment formula looks at your circumstances to work out how much child support should be paid.

How we work out who pays

Normally you’ll either:

  • pay child support if your percentage of care of a child is less than your share of the combined income
  • receive child support if your percentage of care of a child is more than your share of the combined income.

We consider each parent’s income equally when we make a child support assessment. We don’t use income from non-parent carers.

Read more about how your income affects your payment.

How we work out the amount

We look at all of the following:

We work out the costs of a child, based on research about how much parents spend on children in Australia.

The figures change each year to keep up with current costs and incomes.

The basic formula is for parents with only 1 child support assessment.

Read more about working out payments using the basic formula.

You can also read more about the:

What’s the link between child support and Family Tax Benefit

You may need to apply for a child support assessment to receive more than the base rate of Family Tax Benefit Part A.

Normally:

  • the more child support you receive, the less Family Tax Benefit you receive
  • the less child support you receive, the more Family Tax Benefit you receive.
Page last updated: 3 March 2022.
QC 27921