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The child support formula
Every family is unique, and the child support formula is flexible and takes into account many different family circumstances. It ensures a balanced and flexible way of working out child support payments.
The key components of the formula are:
- the costs of raising children, based on independent research, are the basis of the formula
- both parents’ incomes are taken into account and considered equally
- the same self-support amount is deducted from each parent’s income before child support is worked out
- the level of care each parent provides is taken into account
- children from first and subsequent families are treated in a similar way.
We follow eight steps to calculate child support.
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1 Work out your child support income
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If you have dependent children or more than two child support assessments, this will be taken into account at this step.
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2 Work out the combined child support income
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3 Work out your income percentage
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4 Work out your care percentage
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5 Work out your cost percentage
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6 Work out your child support percentage
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7 Work out the cost of your child
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You will get either a positive or negative child support percentage.
If the percentage is positive, you need to pay child support |
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8 Work out the child support amount
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The basic formula
The basic formula applies to parents with one child support assessment and no other dependent children. This is the formula we use for most child support assessments.
Learn more about the basic formula.
Parents with other dependent children
The cost of a biological or adopted child living with a parent is calculated in the same way as the cost of a child support child. To recognise the care a parent provides for these children, called relevant dependent children, we deduct an amount from the parent’s adjusted taxable income before applying the basic formula.
Learn more about the formula for parents with other dependent children.
Parents with two or more child support assessments
The calculations for parents with two or more child support assessments are a little more involved yet are still based on the basic formula.
If you pay or receive child support for two or more families, we deduct an amount—called the multi-case allowance—after we deduct the self-support amount and any relevant dependent child amount from your adjusted taxable income, to arrive at your child support income. We then go on to apply the basic formula.
Learn more about the formula for parents with two or more child support assessments.
You receive child support but are not the parent
If you provide care for a child and you are not the parent, you can receive child support from both parents of the children if you apply for a child support assessment.
Child support is still worked out using both parents’ incomes, cost percentages and child support percentages—similar to how child support is worked out for parents. However, only your cost percentage, based on your level of care, is relevant to working out how much child support is payable—your income is not taken into account.
