Where you may be now
Is the child support amount fair?
The child support formula works well for many families. It is quick and run by the government. But it is based on taxable income, so it can miss what a parent really earns, for example through a business, a trust or bonuses. And it does not always cover the real costs of raising children, like school fees, sport or medical bills.
Whether you pay or receive child support, we can check whether the amount is right and, where it is not, help you change it or agree on something better for your children.
How the law works
The child support system in brief
Child support is governed by the Child Support (Assessment) Act 1989 (Cth) and administered by Services Australia (Child Support). Either parent, or a non-parent carer, can apply for an assessment.
The formula takes each parent's adjusted taxable income, deducts a self-support amount, combines the incomes, applies costs-of-children tables, and allocates responsibility according to each parent's income share and care percentage. A parent with care of at least 14% of nights receives credit for part of the cost of the children, and that credit increases substantially once care reaches 35% (shared care). Below 14%, there is no credit for care.
Agreements
Parents can make:
- a limited child support agreement, which requires an assessment to be in place and an annual amount at least equal to it; or
- a binding child support agreement, which can set any amount or form of payment but requires each parent to receive independent legal advice, evidenced by signed certificates. Binding agreements are difficult to vary or end.
Change of assessment
Where special circumstances exist (including high costs of caring for a child, private school fees the parents intended, or where a parent's income, earning capacity, property or financial resources are not reflected in the assessment) either parent can ask Services Australia, or the court, to depart from the formula.
Adult children
Once child support ends, the court can order maintenance for a child over 18 under the Family Law Act 1975 (Cth) where it is necessary to allow the child to complete their education, or because of a disability.
Common situations
When the formula does not fit
Issues we often help with
- A parent who is self-employed or paid through a business or trust
- Income that has dropped suddenly, or been reduced on purpose
- Private school fees and other big costs
- Paying costs directly instead of paying child support
- Changes in how much time the children spend with each parent
- How child support fits with the property settlement
Many families find a private child support agreement gives both parents certainty: the paying parent knows exactly what they owe, and the other parent knows the important costs will be covered.
How we help
Certainty for both homes
We start with the numbers: what the formula produces, what the children's actual costs are, and what each parent can genuinely afford. From there, we recommend whether to rely on the assessment, pursue a change of assessment, or negotiate an agreement, and we draft agreements that anticipate the questions most likely to cause disputes later.
See also parenting arrangements and spousal maintenance.
Last reviewed 27 September 2026 · General information only, not legal advice