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Child support estimates 277-07040000



This document outlines how to take a child support income estimate and includes checking the estimate, customer contact and estimate decision making.

Estimates of income

Customers can make an election for the child support assessment to be based on their estimated Adjusted Taxable Income (ATI) for the relevant financial year. The election is made for:

  • the full financial year if lodged on 1 July, or
  • the remainder of the financial year if lodged after 1 July. If lodged after 1 July, the estimate is made up of the:
    • Year to Date (YTD) ATI, and
    • estimated ATI for the remaining period of the financial year

Note: for Child support estimates (pre 1 July 2010), a different procedure applied.

Validity Rules

An estimate will be valid if:

  • it applies to a period where there is a Child Support assessment made under the Child Support (Assessment) Act 1989
  • there is no Income Amount Order (IAO) relating to the estimating parent in force on the start day of election or any part of the remainder of the financial year for any children of the assessment. An IAO is where a Court Order, Agreement, or COA (Change of Assessment) decision sets the Adjusted Taxable Income, Child Support Income, Annual Rate or Periodic Amount
  • the income used in the assessment at the time of the initial estimate is either:
    • an Australian Taxation Office (ATO) taxable income
    • an Income Tax Declaration (ITD), or
    • an income advised by an overseas authority
  • the first election is not more than 85% of the person’s ATI for the Last Relevant Year of Income (LRYI)
  • the YTD ATI has been provided if initial estimate with start date after 1 July, and
  • it has been lodged by the customer or a person with legal power of attorney or other legal authority to act for the customer

Lodging and updating an estimate

Customers can lodge and update their estimate:

  • online. Encourage and assist customers to use:
    • their Child Support online account via myGov > Income > Update your current income, or
    • Express Plus Child Support mobile app
  • by phone, using the Child Support Enquiry Line
  • in writing. Customers can post or fax a completed Estimate of income for use in Child Support Assessment form (CS1670) and submit it:
    • via their Child Support online account through myGov
    • by post or fax
    • in person at a service centre

Start date of estimate

  • From April each year, customers can lodge an estimate to start in the new financial year on 1 July. If an estimate is lodged to start on a date between 1 April and 30 June, it may also be appropriate for an estimate to be taken for the new financial year starting on 1 July

An initial estimate may also be lodged from:

  • the first date of a new Child Support Period (CS Period) if notified on or before that date. For example, a new CS Period using a higher income is due to start on 1 September. The customer calls in August and elects to start their estimate from the first date of the CS Period (1 September)
  • the date of notification. For example, a customer first notifies of their estimated income on 20 December saying their income reduced in November. The estimate start date is 20 December, or
  • a retrospective date only in circumstances where Child Support has deemed the notification date to have been earlier, see Estimate Deeming Policies

A customer can update their estimate:

  • within the relevant year of income at any time on an active case, for a higher or lower estimated amount than the previous estimate, or
  • after the year of income has ended, if the estimate has not yet been reconciled and the effective date of the new estimate is within the estimate period. For example, if the the new estimate is higher than the last estimate and applies from a date within the estimate period
  • on an ended case, only where the estimate has not yet been reconciled, and if the effective date of the new estimate is before the case ended

Note: when a new child support period begins in a financial year with an accepted estimate already in place, the assessment will continue to be based on that estimate. The assessment only reverts to using the LYRI for the child support period when the next financial year starts. This will be different to the LRYI that applied when the estimate was lodged in the previous child support period. The customer may then be able to lodge a new estimate for that new financial year if appropriate.

Reviewing estimates

If Child Support becomes aware that an estimate has become inaccurate, an estimate review may be required. An estimate review may update the income used in the child support assessment to more accurately reflect the customer’s actual income.

Note: if the customer can make a subsequent estimate for the financial year, this is the preferred option.

Reconciling estimates

At the end of the financial year, the customer’s estimate is checked for accuracy against their tax return. If the customer does not lodge their tax return by 30 June of the following financial year, the Registrar may determine the customer’s actual income.

If the customer has:

  • underestimated their income:
    • the child support assessment may be amended
    • this may create a debt that the customer will be required to pay
    • if the actual income is 10% higher than the estimated amount, the customer may also be charged an estimate penalty
  • overestimated their income:
    • the estimate cannot be backdated
    • the child support income assessment cannot be reduced to reflect the lower income

Options other than an estimate

Options other than an estimate which may be appropriate for the customer include:

Note: for information on lodging an estimate for a notional assessment, see Notional assessment relating to child support agreements.

The Resources page contains links to macros, estimate deeming policies, contact details and the Services Australia website.

Conversation guidelines for Child Support estimates

Initial Estimate in Pluto

Child Support estimates review (post 1 July 2010)

Child Support information gathering powers

Contact with Child Support customers

Documenting Child Support information

Fixed annual rate not to apply applications

Income processing for Child Support customers

Minimum annual rate to nil - Reducing Child Support assessments

Using Child Support self service

Post separation income for Child Support customers

Residency decisions for Child Support customers

Technical support in Child Support

Assessments Cuba Process Help

CSAOnline secure message Cuba Process Help

Estimates Cuba Process Help

Intray management Cuba Process Help

Letters Cuba Process Help

Client Income Window Help

Estimate income Window Help

Income Details Window Help