New information

• The Registrar may receive new information about a parent's ATI (Adjusted Taxable Income). There are rules about whether this new information can be used to amend a parent's child support assessment.
• Where new information about the parent's income is as a result of an amended tax assessment issued by the ATO, different rules apply.
• When the Registrar receives new information about a person's taxable income


  1. The relevant child support assessment may be updated depending on the period the income will apply to

  2. Legislative changes introduced new rules for assessments from 1 July 2008

  3. The Family Assistance and Child Support Legislation Amendment (Protecting Children) Act 2018 further amended the rules from 23 May 2018 for child support periods that commenced before 1 July 2008, to align with the rules used for child support periods that commenced on or after 1 July 2008

  4. The changes introduced by the Families, Housing, Community Services and Indigenous Affairs and Other Legislation Amendment (Further Election Commitments and Other Measures) Act 2011 apply to child support periods starting on or after 1 July 2011
• New information about ATI

  1. The assessment must be amended immediately if the Registrar ascertains the parent's actual taxable income or makes a later determination of the appropriate ATI amount

  2. If more recent income information becomes available, another ATI will be determined and the assessment will be amended to use the more recent information
• If the parent lodged their tax return on time

  The date of effect of the amendment to the child support assessment will be the beginning of the relevant child support period
• If the parent does not lodge their tax return on time

  The date of effect of the amendment to the child support assessment will take effect from the day after the assessment was amended, for the remainder of the child support period, unless certain circumstances apply
• Exceptional circumstances


  When making a decision about whether the circumstances prescribed by CSA Regs section 11 apply, the Registrar must consider all the relevant facts of the parent's particular circumstances and the extent to which they contributed to the parent's delay in providing information about their income to the Registrar
• Exceptional circumstances


  • Unaware that an assessment had been made; serious ill health or injury; natural disaster; remote location; imprisonment; or other exceptional circumstances
• If the Registrar is satisfied that exceptional circumstances apply, the assessment can be amended to use the new ATI retrospectively.
• New information about incomes used before 1 July 2008


  1. If the Registrar has based a parent's child support assessment on a default income, and the parent's taxable income and/or supplementary amount is subsequently ascertained and:

  2. The new amount is lower than the previous income amount, the Registrar would not amend the child support assessment

  3. The new amount is higher than the previous income amount, the Registrar must amend the child support assessment
• New information about incomes used before 1 July 2008


  • Daniel's taxable income and supplementary amounts cannot be ascertained because Daniel hasn't lodged a tax return for the relevant year (2006-07). The Registrar can make a child support assessment using an income amount considered appropriate and decides to use an amount of $32,000 based on Daniel's past income history. Daniel later lodges a tax return for the 2006-07 year and his taxable income is assessed to be $28,000 and there are no supplementary amounts. The Registrar does not amend the child support assessment as Daniel's actual taxable income of $28,000 is lower than the default income used by the Registrar.