How is child support normally calculated in Australia?
Services Australia administers a formula-based assessment that uses both parents' incomes, the percentage of care each parent provides, and a cost-of-children table based on the number of children and their ages. The formula is designed to be fair in the average case — but most families aren't average, and the standard assessment leaves significant gaps.
Common things the assessment does not cover:
- Private school fees and uniforms
- Significant medical, dental or therapy costs
- Extracurricular activities (sport, music, tutoring)
- Travel costs for contact arrangements
- Higher costs in the child's early years
This is the gap mediation fills — building a complete, child-specific arrangement that works alongside the assessment.
Private vs binding child support agreements
| Limited agreement | Binding agreement | |
|---|---|---|
| Requires independent legal advice | No | Yes — each parent must have their own lawyer |
| Can depart from the assessment | Only if the amount equals or exceeds the assessment | Yes — can be above or below the assessment |
| How it's changed | Either party can end it with 3 months' notice | Only by court order or a new binding agreement |
| Best for | Topping up the assessment for special expenses | Comprehensive private arrangements departing from the formula |
For most families, a limited agreement (covering the formula plus agreed special expenses) is the simplest path. A binding agreement suits families with complex or high-cost arrangements. Mediation helps you choose the right structure and agree the terms. See financial agreements →
What can child support mediation actually resolve?
- Special expenses — how private school fees, medical costs, and activity expenses are split
- Departures from the assessment — where the standard formula doesn't reflect the family's actual arrangements
- Changes in circumstances — loss of employment, relocation, change in care percentage
- Disputes about care percentages — the assessment depends on how much time each parent has the children
- International arrangements — where one parent moves overseas
- Enforcement concerns — addressing recurring non-payment before it becomes entrenched
A worked example: where the formula falls short
Consider a family with two children at a private school where fees are $15,000 per year per child. The Services Australia assessment covers ordinary costs of children based on a generic table — it doesn't know about private school fees, and won't automatically divide them. Without a separate agreement, one parent typically ends up carrying the entire fee while the other relies on the formula payment.
In mediation, the parents agree to split school fees 60/40 (reflecting their incomes), add a shared medical account for unplanned health costs, and increase the base payment modestly for the years of highest activity costs. That complete arrangement is formalised as a limited child support agreement and registered with Services Australia. Both parents know exactly where they stand — and the argument over the fee account ends.
Pairs naturally with your parenting plan
Financial and parenting arrangements are deeply connected — child support depends on the care percentage, which is what the parenting plan sets. Mediating both together in one session produces a consistent, coherent outcome for your children. See parenting plan mediation →
What if the other parent won't pay what's owed?
Services Australia has collection and enforcement powers for registered assessments — including intercepting tax refunds, registering charges on property, and suspending driver's licences in serious cases. Mediation is most valuable before enforcement becomes necessary: resolving the underlying dispute (often a disagreement about the care percentage or special expenses, not unwillingness to support the children) prevents the conflict recurring. Where enforcement is already underway, mediation can help recalibrate the arrangement so it actually works.