Adjusted Taxable Income

Adjusted taxable income starts with the taxable income on your tax return, but it does not always stop there. In child support, Services Australia may add back amounts that do not appear to be ordinary take-home pay, so the figure better reflects the income available to support children.

Definition

A parent’s ATI is the total of the following components:

  • the parent’s taxable income
  • the parent’s reportable fringe benefits total
  • the parent’s target foreign income
  • the parent’s total net investment loss
  • the total of the tax free pensions or benefits
  • the parent’s reportable superannuation contributions

Amounts not included in ATI:

  • the parent’s assessable First Home Super Saver released amount for that year of income is not included in taxable income
  • National Disability Insurance Scheme (NDIS) amounts
  • National Redress Scheme payments
  • Territories Stolen Generation Redress Scheme payments

The year of income for ATI is the last relevant year of income, unless the parent has lodged an estimate of income. When an estimate of income for a year has been lodged, the relevant year of income is the current financial year.

Definition source: Guides to Social Policy Law, Child Support Guide, Version 4.97, released 20 March 2026, 1.1.A.20 Adjusted taxable income.

Role in the formula

Adjusted taxable income is the starting income figure for each parent in child support. It extends beyond taxable income to capture income that may not appear in a standard tax return but still reflects financial capacity.

Adjusted taxable income
taxable income + fringe benefits + foreign income + net investment losses + tax-free pensions/benefits + reportable super contributions

For many parents, taxable income and adjusted taxable income are the same. A key reason for making the adjustments is to prevent parents artificially lowering their reported income for child support purposes.

When using a calculator, you need to include these adjustments. If you only enter taxable income where add-backs apply, your estimate will be too low.

Example

A parent earns $100,000 in salary and salary sacrifices an extra $10,000 into superannuation. Their taxable income may show as $90,000, because the sacrificed amount is no longer counted in ordinary taxable income.

Woman carrying shopping bags with man and trolley in background, illustrating income considered in child support calculations

For child support purposes, the $10,000 reportable superannuation contribution is added back. That gives the parent an adjusted taxable income of $100,000. Services Australia uses the higher figure because the super contribution reflects income that was available to the parent before it was directed into super.

The same issue applies when using a calculator, including the Services Australia estimator. If your taxable income has been reduced by salary-sacrificed super contributions, you need to add those reportable contributions back before entering your income, or your estimate will understate your child support income position.

ATI vs Child Support Income

Child support income is calculated by making further adjustments to adjusted taxable income. The main one is to subtract the self-support amount that covers basic living costs for all parents.

Child support income
ATI − self-support amount − relevant dependent child amount − multi-case allowance

The self-support amount applies in every case. The other deductions only apply in some cases.