Family Law Services › Child Support
Child Support Lawyers — Disputes, Change of Assessment & Enforcement
Child support is assessed by Services Australia using a formula based on both parents' incomes, care time, and the child's age. But the formula does not always produce a fair result — and change of assessment, private agreements, and enforcement are all areas where a lawyer can make a significant difference. Get connected with a family lawyer today.
⚠ A change of assessment application must be lodged within 18 months of the relevant assessment period in most cases. Enforcement and arrears matters should not be delayed. Get advice now.
What We Help With
Child support disputes and issues — covered at every stage.
From challenging an assessment that doesn't reflect the real situation, to enforcing payment from a non-paying parent, to negotiating a private child support agreement — a lawyer provides options beyond the standard Services Australia formula.
Change of Assessment (CoA)
Applying to Services Australia for a departure from the formula-based assessment — on grounds including high income, special expenses, reduced earning capacity, or significant care changes.
AAT Appeals — Child Support
Appealing a Services Australia child support decision to the Administrative Appeals Tribunal (AAT) — where the internal review has not produced a fair outcome.
Private Child Support Agreements
Negotiating and formalising a binding child support agreement — a legally enforceable private arrangement outside the Services Australia formula.
Enforcement of Arrears
Pursuing a parent who has failed to pay assessed child support — including enforcement through the Child Support Register, garnishment of wages, and court proceedings.
Income Disclosure Issues
Where a paying parent has concealed income, diverted income through a business, or declared a significantly lower income than their true capacity to earn.
Overseas Child Support
Enforcing or collecting child support where a parent lives overseas — including through reciprocating countries under Australia's international child support agreements.
How Child Support Works in Australia
When the formula doesn't reflect reality — and what you can do.
The Services Australia child support formula produces an assessment — but it can be changed in 10 specific circumstances. Understanding these grounds is the key to a fair outcome.
The formula assessment — how it works
Services Australia calculates child support using the Child Support (Assessment) Act 1989. The formula considers both parents' taxable incomes, the percentage of care each parent provides, and the costs of raising children at different ages. The result is a fortnightly or monthly payment from the higher-income, lower-care parent to the lower-income, higher-care parent. The formula is a starting point — not a fixed outcome.
Change of Assessment — 10 grounds for departure
A change of assessment (CoA) can depart from the formula amount on 10 specific grounds under section 117 of the Child Support Act — including where the child has special expenses (education, medical), a parent's income does not reflect their earning capacity, care arrangements have changed significantly, or a parent has a high income that the formula doesn't fully capture. Legal advice maximises the chance of a successful CoA application.
Binding child support agreements — more than the formula
A binding child support agreement — signed with independent legal advice by both parties — can set child support at a level above, below, or different in structure from the formula assessment. It can include non-cash support (school fees, health insurance) and provides certainty for both parties. Once registered, it operates outside the Services Australia system and is enforceable as a court order.
Concealed income — what the law allows
If a paying parent structures their affairs to minimise taxable income — through a private company, trust distributions, or salary packaging — Services Australia can assess them on their "capacity to earn" rather than their declared income. A change of assessment on the ground of high income or income diversion is one of the most effective tools available to a receiving parent in this situation. Financial disclosure obligations are strict.
Enforcement — collecting overdue child support
Services Australia's Child Support Registrar has broad enforcement powers — including intercepting tax refunds, garnishing wages, deducting from Centrelink payments, and placing departure prohibitions on parents with significant arrears. Where administrative enforcement is insufficient, court proceedings can be commenced to recover arrears. Legal advice can identify the most efficient enforcement pathway for your specific situation.
AAT appeals — challenging an unfair decision
If Services Australia's decision on a change of assessment, objection, or registration matter is unfair, an appeal to the Administrative Appeals Tribunal (AAT) can be lodged. The AAT conducts a merits review — it can substitute a different decision if the original was wrong. Time limits apply to AAT applications and strict procedural rules govern the process. Legal representation significantly improves AAT appeal outcomes.
How It Works
One request. The right child support lawyer.
Describe your child support issue — whether you are the payer or receiver, what the dispute is about, and any deadlines. A family lawyer will follow up for a free consultation.
Submit Your RequestDescribe your child support issue
Tell us whether you are the payer or receiver, what the assessment is, what the dispute involves, and any decisions or deadlines from Services Australia.
Matched to a family lawyer
Your request is matched to a family lawyer experienced in child support change of assessment, AAT appeals, and enforcement matters.
Free consultation arranged
A family lawyer contacts you for a free consultation — advising on grounds for a change of assessment, enforcement options, or appeal rights.
Common Questions
Child support — frequently asked questions.
Can I change the amount of child support I pay or receive?
Yes — through a change of assessment (CoA) application to Services Australia on one of the 10 grounds in section 117 of the Child Support Act, or by negotiating a binding child support agreement. A CoA is assessed by a registrar who can depart from the formula if one of the grounds is made out. Legal advice before lodging a CoA maximises the prospects of success.
What can I do if the other parent is not paying child support?
Services Australia has enforcement powers including wage garnishment, tax refund interception, and Centrelink deduction. If the payer is self-employed or has no Centrelink payments, these tools may be less effective. Legal advice can identify additional enforcement options — including court proceedings for arrears, departure prohibition orders (preventing the payer from leaving Australia), and applications to the court for a costs order.
The other parent earns a lot through their business but pays minimal tax — what can I do?
A change of assessment on the ground of income diversion or earning capacity allows Services Australia to assess the payer's support obligation based on their actual capacity to earn — not their declared taxable income. Evidence of business income, director's fees, trust distributions, and lifestyle inconsistent with declared income is relevant. A family lawyer can advise on gathering this evidence and presenting the CoA application effectively.
Can I make a private agreement with the other parent about child support?
Yes — a binding child support agreement allows both parents to agree on a different amount, structure, or payment method outside the Services Australia formula. Each party must obtain independent legal advice before signing. Once registered, the agreement operates like a court order. It provides certainty and can include things the formula doesn't cover — like school fees, medical expenses, and extracurricular costs.