Articles and Resources

Tools, articles and other help for Australian parents, with the latest posts in each category.

  • Child Support Calculator Australia

    Child Support Calculator Australia Estimate your Australian child support payments for 2026. Solid calculator built using the official 8-step formula. Understanding Your Result The estimate is calculated using the legislated Australian child support formula. The calculator uses the same calculation applied by Services Australia. You can adjust the inputs and see how the assessment changes….

Assessment of child support ›

A child support assessment is the formal determination of how much child support is payable between parents. It usually comes from the standard formula applied by Services Australia.

  • Court order for child maintenance

    A court order for child maintenance is a court-set child support obligation, used where the standard administrative assessment does not apply.

  • Limited child support agreement

    A limited child support agreement is a written agreement that sets child support at or above the assessed rate without legal advice.

Care arrangements ›

Care percentage is the share of time a parent looks after a child over a care period. It is almost always based on the number of nights the child stays with each parent.

  • Relevant dependent child

    A relevant dependent child is your child outside the case. Their costs reduce your income before child support is calculated.

  • Below regular care

    Below regular care means 0 to 51 nights a year. The formula treats that parent as meeting none of the child’s costs through care directly.

Change of assessment ›

Change of Assessment (COA) is a way to adjust a child support assessment when the formula does not properly reflect a case situation. Either parent can apply.

  • Reason 8B

    Reason 8B allows child support to reflect a parent’s unrealised earning capacity where current income is lower than they could earn.

  • Reason 8A

    Reason 8A allows child support to reflect a parent’s true financial capacity, including assets and business resources, beyond taxable income.

Enforcement and debt collection ›

Child support debt arises when assessed payments are not made and the case is being collected by Services Australia. The unpaid amount becomes a debt owed to the Commonwealth.

  • Child support debt

    Child support debt is an amount owed to the Commonwealth under a registered liability. It arises from unpaid amounts and remains enforceable.

Family law ›

Formula for child support ›

The child support formula is also known as the basic formula and formula 1. It is a complex calculation that uses an income shares model to make a child support assessment.

  • Multi-case allowance

    Multi-case allowance is a deduction from income for other child support cases, reducing assessed income before payments are calculated.

  • Self-support amount

    The self-support amount is the income deducted for a parent’s own living costs before child support is calculated.

Income for child support ›

Child support income is calculated from the taxable income of the parent. The main adjustment is to subtract a self-support amount in excess of $30k to determine income available to support children.

  • Income percentage

    Income percentage is each parent’s share of combined child support income after deductions, used to calculate payment responsibility.

  • Taxable income

    Taxable income is assessable income minus deductions. It forms the base for personal tax and underpins income measurement in child support.

Objections and reviews ›

An objection is the first step if you believe a child support decision is wrong. It triggers an internal review by Services Australia, where a different officer reassesses the decision.

  • Administrative Review Tribunal

    The Administrative Review Tribunal reviews child support objection decisions independently and can affirm, vary, or replace the outcome.

Parenting ›

Payments ›

Q&A Forum ›

  • CSA Complaints Forum

    About this forum This is a public Q&A space where parents ask questions about how child support actually works in Australia. I’ve been answering these questions since 2017 and have responded to thousands of real situations over that time. The forum has gone a bit quieter since AI came along, which is understandable. But I…

Rules ›