Child Support in Australia: The 2026 Formula and Rates

Child support in Australia is assessed administratively by Services Australia under the Child Support (Assessment) Act 1989, not by a family law court. For the 2026 Child Support Period, the self-support amount is $31,046, the minimum annual rate is $551, and the fixed annual rate is $1,825 per child.

This article addresses child support assessed administratively under the Child Support (Assessment) Act 1989 (Cth). It does not address child maintenance orders made by a family law court under Part VII Division 7 of the Family Law Act 1975, which apply only in limited circumstances where an administrative assessment is not available.

Child support is separate from the Family Law Act

Child support in Australia is not decided by the FCFCOA applying the Family Law Act. It is assessed administratively by Services Australia, the Commonwealth agency responsible for social security and family payments, under a different statute entirely: the Child Support (Assessment) Act 1989. Most separated parents never need to go to a family law court for child support at all; they apply to Services Australia, which calculates and can also collect the assessed amount. Family law courts become involved only in narrow circumstances, such as an application to depart from an administrative assessment because of special circumstances, or a child maintenance order for a child not covered by the administrative scheme. Property settlement and spousal maintenance, by contrast, remain matters for the Family Law Act and the FCFCOA. Section 79(4)(g) and 79(5)(s) of the Family Law Act do, however, allow a property settlement court to take existing or likely future child support into account as one contextual factor among many.

The eight-step formula

The child support formula in Part 5 of the Child Support (Assessment) Act 1989 works through a defined sequence. Broadly: each parent's adjusted taxable income is worked out; a self-support amount is deducted from each parent's income, reflecting the cost of supporting themselves; the parents' remaining incomes are combined; each parent's percentage of the combined income is calculated; each parent's percentage of care of the child is determined and converted to a cost percentage; each parent's child support percentage is found by subtracting their cost percentage from their income percentage; the total cost of the children is worked out using the Costs of the Children Table, based on the parents' combined income and the number and ages of the children; and finally, a parent with a positive child support percentage pays the other parent that percentage of the total cost of the children. Fixed and minimum rates apply instead in certain low-income situations.

The 2026 figures, and why they index on 1 January

Several of the values in the formula are indexed annually, but not on the same schedule as most other Australian legal fees. Where FCFCOA court fees update on 1 July, the core child support figures update at the start of each calendar year, tied to each Child Support Period rather than the financial year. For the 2026 Child Support Period, the self-support amount is $31,046, the minimum annual rate is $551, and the fixed annual rate is $1,825 per child, according to the Department of Social Services' Child Support Guide. These figures have risen each year: the self-support amount was $28,463 in 2024 and $29,841 in 2025 before reaching $31,046 in 2026; the fixed annual rate moved from $1,720 to $1,768 to $1,825 over the same period; and the minimum annual rate moved from $519 to $534 to $551.

Minimum and fixed rates: when the standard formula does not apply

Not every assessment uses the full income-based formula. The minimum annual rate applies where a parent's formula-calculated liability would otherwise be less than the minimum rate, that parent has below-regular care of all the children in the assessment, and the fixed annual rate does not apply; it is capped at 3 times the minimum rate for a parent with more than 3 child support cases, shared proportionally across those cases. The fixed annual rate applies instead where a parent did not receive an income support payment in the relevant year, their income was below the pension parenting payment (single) maximum basic amount, and they have less than shared care (under 35 per cent) of the child; it too is capped at 3 times the rate for more than 3 children, apportioned between them. A parent assessed at either rate can apply for it not to apply if their real capacity to pay is genuinely lower.

The Costs of the Children Table

The Costs of the Children Table, published as Schedule 1 to the Child Support (Assessment) Act 1989 and updated annually by the Department of Social Services, sets the dollar cost attributed to raising children at different levels of combined parental income, banded by reference to average weekly earnings, and varying by the number of children and whether they are aged under 13, 13 and over, or a mixed-age group. The table is the mechanism that converts the parents' combined income into a total children's cost figure, which is then apportioned between the parents according to their respective child support percentages calculated earlier in the eight-step process.

Every unofficial figure is an estimate only

Because the formula depends on each parent's adjusted taxable income, percentage of care, and the current Costs of the Children Table, any calculation performed outside an actual Services Australia assessment, including examples in this guide, is an estimate only. It cannot account for every element Services Australia considers, such as relevant dependent child amounts or multi-case allowances. See the child support calculator explainer for a worked example, and apply directly to Services Australia, or use its own online tools, for a binding figure.

Changing or agreeing an assessment

Parents can also agree their own child support arrangement through a binding or limited child support agreement under Part 6 of the Child Support (Assessment) Act 1989, which Services Australia can accept and administer instead of the standard formula assessment. A binding child support agreement can set an amount above or below the formula assessment and is harder to end than a limited agreement, which generally requires the amount to be at least equal to the formula rate. Where a parent believes the formula assessment does not reflect their actual capacity to pay or receive child support because of special circumstances, such as high costs of maintaining contact with the child or a medical condition affecting earning capacity, they can apply to Services Australia for a change of assessment, or in some cases to a court, for a departure determination under Part 6A or Part 7 of the Act.

How child support periods work

Child support is not assessed once and left unchanged indefinitely. Each assessment applies for a defined child support period, which generally ends no later than 15 months after it started, or earlier once a new income tax assessment issues for one of the parents, at which point Services Australia recalculates the assessment for the following period using updated income information. A parent can also lodge an income estimate during a period if their income changes significantly, which can adjust the assessment before the period would otherwise end. This periodic recalculation is one reason the figures in this guide, including the 2026 self-support amount, minimum annual rate and fixed annual rate, are tied to a specific Child Support Period rather than fixed permanently.

This page provides general legal information about child support in Australia, verified 20 July 2026. It is not legal advice about your own child support assessment. For your specific figure, contact Services Australia; for legal advice, consult a legal practitioner admitted in the relevant Australian state or territory.

For a worked walkthrough of the formula, see the child support calculator explainer. For dividing property, which is assessed separately, see property settlement in Australia. For ongoing support between former partners, see spousal maintenance in Australia. For the full picture, return to the Australian family law hub.