The Guides to Social Policy Law is a collection of publications designed to assist decision makers administering social policy law. The information contained in this publication is intended only as a guide to relevant legislation/policy. The information is accurate as at the date listed at the bottom of the page, but may be subject to change. To discuss individual circumstances please contact Services Australia.

2.5.1 Income estimates for a year of income


Child support assessments are generally based on both parents’ ATI from the last relevant financial year and the level of care they provide for their children. If a parent’s income has reduced by 15% or more from the income used in their assessment, they can elect for their assessment to be based on an estimate of their current income.

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Frequently asked questions

Why are parents allowed to have their child support assessment based on an estimate of income?

A key objective of the Child Support Scheme is that parents financially support their children after separation, based on their financial capacity.

Income estimates recognise that larger reductions in a parent’s income (that is, at least 15%) may affect their capacity to meet their financial obligations and ability to provide financial support to their children. Smaller changes to a parent’s income are considered to have less of an immediate impact on their financial circumstances, and will be reflected in their ATI for their child support assessment in the following year. This helps to maintain a reasonable level of stability in assessments and changes in income will still be reflected in future assessments without the need for frequent readjustments.

Is there any discretion as to how a parent’s ATI is determined during an estimate review?

No. The ATI must reflect the parent's ATI that will be earned from the event date (or notification date) until the end of the estimate period.

How is an estimate reviewed when a lump sum has been received?

Lump sums are treated no differently to 'regular' assessable income. Receipt of a lump sum will usually be an event for reviewing purposes. The Registrar needs to work out the income earned from the event date (or notification date) until the end of the original estimate period taking into account any assessable lump sum payment within that period.

WA ex-nuptial cases

The information relating to income estimates applies to WA ex-nuptial cases from a later date than for other cases. See 1.2.3 for details of the date from which various provisions had effect for WA ex-nuptial cases.

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