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Challenging A Child Support Assessment


 Under the Child Support (Assessment Act) 1989, a parent must pay to maintain a child via child support payments. Child support is a continuing regular payment made by a parent of a child after the end of a relationship. It is usually paid until a child turns 18.  Child support is governed by principles including that each parent is responsible for helping to meet the costs of children, that costs depend on the number and ages of children, and that parents who earn more must contribute more.

In most cases, the payment of child support is dictated by an assessment issued by the Child Support Agency (CSA), part of Services Australia. A parent who has an obligation to pay child support or the parent entitled to receive it can lodge an objection to the assessment, first with the CSA, then to the Administrative Appeals Tribunal (AAT), then to a court.

Calculating child support

The CSA has an 8-step formula for calculating child support:

1 Determine each parent’s income

2 Combine the incomes

3 Calculate each parent’s income percentage

4 Calculate each parent’s percentage of care

5 Calculate each parent’s cost percentage

6 Calculate each parent’s child support percentage (subtract cost percentage from income percentage for each parent)

7 Calculate the costs of the child

8 Calculate the child support amount (multiply the costs of the child by the positive child support percentage)

A person pays child support if the result is positive and receive child support if it is negative.

The agency provides Costs of Children tables for children aged 12 and under, children aged 13 or older, and children of mixed ages.

Calculations for parents who have two or more child support assessments are also based on the formula but are more complex.

A non-parent carer can apply for child support if they meet certain criteria.

Changes of circumstances

Changes to circumstances can affect the amount of child support payable. For example:

  • care arrangements: the percentage of care calculated in the child support assessment will change.
  • income: the amount of child support payments will be affected
  • reconciliation: if parents reconcile, child support can be suspended for up to six months. If the parents separate again within the six months, child support can be resumed.
  • more children: if a parent has a child with a new partner, and is required to pay child support for this child, existing child support arrangements will likely be affected.

The CSA should be notified of changes of circumstances to avoid incorrect payments such as an overpayment or accumulation of debt.

Challenging an assessment

There are several avenues to appeal a child support assessment.

Review by the CSA

An objection must be filed within 28 days of an assessment. There are many reasons a parent may object to an assessment. The reason could be an administrative one, such as an incorrect calculation of income or percentage of care. It could also be that there are special circumstances that need to be taken into account. A CSA officer can review an original assessment against one or more special circumstances listed in the Act. These are:

  • significant costs of spending time or communicating with the child;
  • significant costs associated with a child’s special needs;
  • significant costs in caring for, educating or training the child in a way the parent and their former spouse intended (e.g. private schooling);
  • the assessment is unfair because of the child’s income, earning capacity, property or financial resources;
  • the assessment is unfair because the parent has paid or transferred money, goods or property to the child, the child’s other parent, or a third party for the benefit of the child;
  • the parent’s necessary expenses significantly reduce their capacity to pay child support;
  • the assessment is unfair because of the income, earning capacity, property or financial resources of one or both parents;
  • the parent’s capacity to pay child support is significantly affected by:
    • their duty to maintain another child or person;
    • their necessary expenses to support another child or person they have a duty to maintain;
    • the significant costs of spending time or communicating with another child or person they have a duty to maintain;
    • their responsibility to maintain a resident child significantly reduces their capacity to pay child support another child.

Review by the AAT

If the CSA review is not successful, a parent can challenge the review decision by appealing to the AAT. The first review is conducted by the Social Services & Child Support Division of the AAT. A second review can be conducted by the General Division of the AAT but only of a decision to refuse an extension of time to apply for a first review, or about a parent’s percentage of care for a child.

Review by the courts

A parent can apply for a review of an AAT decision to the Family Court or the Federal Circuit Court.

For advice or representation in any legal matter, please contact Armstrong Legal.

Sally Crosswell

This article was written by Sally Crosswell

Sally Crosswell has a Bachelor of Laws (Hons), a Bachelor of Communication and a Master of International and Community Development. She also completed a Graduate Diploma of Legal Practice at the College of Law. A former journalist, Sally has a keen interest in human rights law.

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