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2.5.5 Application to have an assessment continue past a child's 18th birthday

Context

A carer (parent or non-parent carer) entitled to child support for a child who is turning 18 can apply to extend a child support assessment (including one based on an agreement) provided the child will be in full-time secondary education on their 18th birthday. The child support assessment can be extended until the last day of the secondary school year in which a child turns 18, as long as the child’s 18th birthday is during the calendar year in which they will be undertaking full-time secondary education. In this topic, this is referred to as a CSA Act section 151B application.

A carer entitled to child support is not able to apply for an age 18 extension in respect of a child who turns 18 after the conclusion of a secondary school year and before the commencement of the next calendar year. A parent who has a relevant dependent child who is turning 18 can apply to have the relevant dependent child taken into account in any relevant administrative assessment provided the relevant dependent child will be in full-time secondary education on their 18th birthday. The relevant dependent child can be taken into account in any relevant administrative assessment until the last day of the secondary school year consistent with that described for child support children turning 18.

Note: FTB payments may be affected (reduced) if a parent does not apply for an extension of child support for a child who is turning 18 years and is in full-time secondary education (or an exemption from the FTB Part A maintenance action test). Further information regarding entitlement to FTB is available in FA Guide 3.1.5.40.

Act references

CSA Act section 5-‘full-time secondary education’, section 5-‘last day’, section 5-‘secondary school’, section 12, section 34B, section 84, section 93, section 151B, section 151C, section 151D and section 151E

FL Act section 66E

On this page

Continuing a child support assessment beyond a child’s 18th birthday

A carer entitled to child support can apply to extend a child support assessment, including an assessment modified by an agreement, until the last day of the school year in which the child turns 18 provided the child will be in full-time secondary education on their 18th birthday (CSA Act section 151B).

Carer entitled to child support

A carer entitled to child support is a parent or non-parent carer who is entitled to receive child support for a child. An application to extend a child support assessment beyond a child's 18th birthday can be made by a carer entitled child support. This will be the person in the child support case who has the child in their care and is entitled to receive child support for the child, regardless of whether they are the overall payee or payer in the case after the liabilities for each child in the case are offset.

How to make an application to continue child support beyond a child’s 18th birthday

A CSA Act section 151B application (made orally or in writing) should include:

  • the name of the child
  • the name of the school or college
  • whether the child will be in full-time secondary education on their 18th birthday
  • the last day of secondary school for the calendar year in which the child turns 18, and
  • if the application relates to a child support agreement that initiated the assessment under CSA Act section 93, the application must be in writing and signed by both parents.

The section 151B application can be made after the child turns 17 (CSA Act section 151C(2)(a)) and must be made before the child's 18th birthday. If in the Registrar's opinion, there are exceptional circumstances justifying the making of the application after the child's 18th birthday, the Registrar may accept an age 18 extension application after the child’s 18th birthday (section 151C(2)(e)(ii)).

Unless the application relates to a child support agreement that initiated the assessment (CSA Act section 93) the extension application does not need to be signed by both parties for it to be accepted.

Continuing a child support application beyond a child’s 18th birthday when there is an agreement

If, on the day before the child's 18th birthday, the child support assessment is or will be based on a child support agreement that initiated the assessment because child support was not already payable (CSA Act section 93), and the agreement:

  • does not specify an end date (that is, more specific than the usual terminating events), both parties must sign the application for extension in order for the application to be accepted and to continue the child support agreement beyond the child's 18th birthday (CSA Act section 151B(2)(b)). If both signatures are not received, the assessment cannot be extended beyond the child's 18th birthday, and child support will cease to be payable when the child turns 18 or an earlier terminating event occurs (section 93(1)(h)).
  • does specify an end date (CSA Act section 84(1)(g)), the agreement will end on that end date (or an earlier terminating event) and cannot be extended using a section 151B application. A section 151B application cannot override the specified end date in the agreement. To avoid such an agreement ending before or on a child's 18th birthday, the parties would need to make a new child support agreement before the child turns 18. If an agreement has ended before the child's 18th birthday, either parent or a non-parent carer may apply for an administrative assessment or acceptance of an agreement prior to the child's 18th birthday. Once a new assessment is in place after an application from either parent or a non-parent carer, the carer entitled to child support may make an application to extend the assessment beyond the child’s 18th birthday

Where an agreement specifies an end date that is after the child's 18th birthday, a section 151B application signed by both parties could extend the agreement beyond the child's 18th birthday, but only until the earlier of the agreement end date or the last day of the secondary school year. Without a duly signed application for extension, the agreement would end on the child's 18th birthday (a terminating event).

If the assessment for the child is based on an agreement that commenced when child support was already payable (CSA Act section 34B), then the carer who is entitled to child support may apply for an extension. The section 151B application does not need to be signed by the other party for it to be accepted. If the agreement does not specify an end date (that is, more specific than the usual terminating events), the agreement will continue to modify the assessment after the child turns 18. If the agreement specifies an end date (section 84(1)(g)), and the section 151B application has been accepted, the agreement will cease to modify the assessment after the end date, and the assessment will instead be based on the formula.

A parent of a relevant dependent child can apply to have the relevant dependent child taken into account in the calculation of any relevant child support assessment until the last day of the school year in which the relevant dependent child turns 18 (section 151B(1A)).

Example: A child support agreement that modifies an existing administrative assessment is to continue until 30 June 2025. The child, Bron, turns 18 on 11 July 2025. The agreement cannot continue beyond Bron’s 18th birthday because the agreement will not be in force on the day before Bron turns 18. However, there will be a formula assessment in place after the agreement ends and an application for continuation of that assessment can be made before the child turns 18.

Example: An application from the parent entitled to child support to continue an assessment for child Adam is accepted. The carer entitled to child support and Adam's other parent then enter into a child support agreement before Adam turns 18. There is no end date in the agreement. The agreement continues after Adam turns 18 because the parents were making an agreement to alter an assessment that continues until the end of the school year.

Example: An agreement modifies a pre-existing administrative assessment for the child, Benson and it is not clear from the agreement whether the parents intended that it will continue beyond Benson's 18th birthday. The parent entitled to child support can apply to extend the assessment without the other parent's consent. The Registrar can continue the agreement beyond the child's 18th birthday because the agreement did not end when the child turned 18 so it will continue to affect the assessment beyond the child's 18th birthday.

Example: The Registrar accepts an application to continue a child support agreement that initiated the assessment under section 93 for child support for Annabel. However, after this application was accepted, Annabel's parents then enter into a new agreement before Annabel turns 18, which terminates the previous agreement. Therefore, the assessment will not continue after Annabel turns 18, unless both parents sign a new application to extend the agreement beyond the child's 18th birthday.

Example: A child support agreement that initiated the assessment under section 93 states that child support will be payable at a given rate until Rica's 18th birthday or until Rica finishes year 12, whichever is the later. An application from the parent receiving child support to extend the assessment cannot be accepted without the other parent's signature, despite what the agreement says. In this case, a terminating event - the child's 18th birthday - will occur before the agreement end date, so it would be necessary for both parents to sign an application to extend the agreement beyond the child's 18th birthday. If the requirement for joint signatures in paragraph 151B(2)(b) is not met, the Registrar cannot accept the application to extend the agreement beyond the child's 18th birthday.

Example: An application to continue the recognition of a relevant dependent child, Roxy, after Roxy's 18th birthday is granted. Any assessment where the parent is assessed in respect of other children continues to recognise that Roxy is a relevant dependent child of the parent.

When does the extension to the assessment end?

If the application is for a child of the assessment and the Registrar has accepted the application, the child turning 18 does not constitute a terminating event (CSA Act section 151D(1)). Instead:

  • a terminating event will happen on
    • the last day of the secondary school year, or
    • if the child does not complete the school year, the day the Registrar is satisfied the child ceases to be in full-time secondary education
  • the child is taken to be aged 17 for the purposes of applying Part 5 of the CSA Act until a terminating event happens (section 151D(2A)).

If the application is for a relevant dependent child:

  • the Registrar must amend the assessment to take into account the relevant dependent child until the last day of the school year (CSA Act section 151E(1)), and
  • the child is taken to be aged 17 for the purposes of applying Part 5 of the CSA Act (section 151E(2)) for the period
    • beginning on the child's 18th birthday, and
    • ending on the last day of the secondary school year.

Where an administrative assessment continues after a child turns 18, the provisions of the CSA Act continue to apply, such as to allow the parents to lodge estimates of income (2.5.1), notify of changes in care arrangements (2.2.2), and apply for a change of assessment under CSA Act Part 6A (2.6), in the same way as before the child turned 18.

How the Registrar will make a decision

The Registrar must accept the application (CSA Act section 151C) if satisfied that:

  • the child has turned 17
  • an assessment or agreement is in force (or is likely to be in force) on the day before the child turns 18, or an administrative assessment that takes the child into account is in force (or is likely to be in force) on the day before the child turns 18, or a suspension determination (CSA Act section 150F) provides that child support is not payable in respect of the day before the child turns 18
  • the child is likely to be in full-time secondary education on their 18th birthday
  • the child's 18th birthday will occur on or before the last day of the secondary school year, and
  • the application was made before the child's 18th birthday (or there are, in the Registrar's opinion, exceptional circumstances justifying the making of an application after the child's 18th birthday).

Full-time secondary education

'Full-time secondary education' means education that is determined by the secondary school at which the child is receiving the education to be full-time secondary education (CSA Act section 5).

A child will be considered to be in 'full-time secondary education' during any period that is prescribed by the school to be a term, semester or school holiday break.

'Secondary school' means a school, TAFE college, or any other educational institution, which provides full-time secondary education (section 5). A secondary school also includes a school that caters for the needs of children with learning difficulties and provides a form of education that is not tertiary education.

Example: Alexa has an intellectual disability and attends a school that specifically caters for children with special learning needs. While the curriculum for Alexa's school is different from the curriculum for a child attending a non-special needs secondary school, Alexa's school is still regarded as providing a secondary education.

Example: Martin is studying towards the Higher School Certificate in NSW. Martin's 18th birthday falls in the holiday period between school terms 3 and 4. Martin’s child support assessment can be extended to the end of the secondary school year in the calendar year in which Martin turns 18.

A child may receive a full-time secondary education through distance or online learning provided by a secondary school. Also, a child being home schooled may, in certain circumstances and subject to the relevant state legislation, be in 'full-time secondary education'.

Secondary school years

The commencement of a secondary school year is not confined by reference to the school terms. Rather, secondary school year relates to a year of study within a particular calendar year.

Example: Sergei completed year 11 in 2023. Sergei is turning 18 on 6 January 2024. Sergei’s school commences classes on 28 January 2024. The last day of Sergei’s 2024 secondary school year is 14 November 2024. The child support assessment for Sergei can continue until 14 November 2024.

Example: Ludwig is in full-time secondary education and is turning 18 on 3 September 2024. The assessment can be extended for Ludwig until the end of the 2024 secondary school year.

Some secondary schools, particularly those in the northern hemisphere, have a school year that spans 2 calendar years (for example, August to May). The Registrar can only continue a child support assessment for a child attending these schools up to the last day of secondary school in the calendar year in which the child turned 18.

Example: Trevor attends Jameson School in year 11. The school year for Jameson School begins in August and ends in May. Trevor begins classes for year 11 in August 2023, and turns 18 on 1 September 2023. The assessment can continue until the last day of the secondary school year (the later of the last day of classes or the end of the examination period) in the 2023 calendar year. Trevor’s assessment cannot continue into the 2024 calendar year.

Example: Astrid lives in the UK where the school year ends in June. Astrid turned 18 in March 2023, while in her second-last year of secondary education. Astrid will continue her secondary education after the end of the 2022-23 school year and will finish her secondary education in June 2024. The last day of classes in the 2023 calendar year is 10 December 2023.

As Astrid turned 18 during the 2023 calendar year, the assessment can be extended until the last day of secondary school in the 2023 calendar year (10 December 2023). The assessment for Astrid cannot continue into the 2024 calendar year.

In some secondary schools, the school year may fall within a calendar year, however, the year level for some students may span 2 calendar years. In cases where the child is required to sit an examination, the last day of the secondary school year (CSA Act section 5) will be the later of the last day of classes for the school year or the last day of exams in the calendar year in which the child turned 18.

Last day of secondary school for the year

A secondary school year relates to a year of study within a particular calendar year. The Registrar can continue a child support assessment for a child up to the last day of the school year in the calendar year in which the child turns 18. The last day of the secondary school year is either:

  • if the child is not required to sit an examination, the last day of classes for the calendar year (as determined by the school), or
  • if the child is required to sit an examination in the calendar year, the later of the last day of
    • the period of examinations for the child's year level, or
    • classes for the calendar year (as determined by the school (CSA Act section 5)).

Example: Ariel turns 18 in term 1 of year 12. Ariel attends Smithfield School in year 12 and is required to sit exams at the end of year 12. The last day of classes for year 12 at Smithfield School is 15 November and the last day of the exam period for year 12 at Smithfield School is 10 December. The assessment can continue until 10 December.

Example: Fred attends Campbell School in year 11. The last day of school for year 11 is 10 December 2019. Fred turns 18 in November 2019. Although Fred will return to school in 2020 to complete year 12, the assessment can only continue up to the last day of school in year 11 (that is, 10 December 2019) as this is the school year in which Fred turned 18. The assessment cannot continue to the last day of year 12 in 2020 because Fred turned 18 during the year 11 school year in 2019, not the year 12 school year in 2020, and the assessment can only be extended once.

Repeating a school year

If a child repeats a year of secondary education, the Registrar can continue a child support assessment for the child up to the last day of the repeated secondary school year if the child turns 18 during that school year.

Example: Cornelius completes year 12 in 2023. In order to improve their academic results, Cornelius again enrols in year 12 in 2024.The 2024 school year ends in November 2024 Cornelius turns 18 in March 2024. The assessment can continue until the end of the school year in which Cornelius turns 18, that is November 2024.

Consideration of late applications

The Registrar can accept an application made after the child's 18th birthday if, in the Registrar's opinion, there are exceptional circumstances justifying the making of the application after the child's 18th birthday (CSA Act section 151C(2)(e)(ii)). The following are examples of circumstances that the Registrar may consider 'exceptional' in deciding whether to accept a late application. This is not an exhaustive list and each case must be considered on its own merits.

  • Serious health problems delayed lodgement (written confirmation from a health practitioner will be required).
  • An application for an assessment has been made but not accepted before the child turns 18, and it was unclear whether the child would be in secondary full-time education.
  • The carer was under pressure not to apply (evidence from a person fully aware of the nature and details of the circumstances, for example, a social worker or police officer, will be required).
  • Severe distress or hardship (for example, caused by a disaster such as fire or flood) delayed lodgement.
  • Communication difficulties led to an inability to access information (a result of geographical location, cultural issues, literacy, language difficulties, etc.).

The exceptional circumstances must relate to the reasons that justify the making of the application after the child's 18th birthday and not to the consequences to the individual of making a late application.

Example: Natasha did not make an application to extend the child support assessment prior to child Silvan's 18th birthday. After the child support assessment has ended, Natasha realises that their FTB has been affected and requests that the Registrar consider a late application. The Registrar would refuse the application if there were no exceptional circumstances that justified the application being made after Silvan turned 18.

Notification of & review rights of the decision

If the Registrar refuses an application to extend a child support assessment, the carer who made the application must be advised in writing (CSA Act section 151C(3)). The parents or non-parent carer (if any) can object to the particulars of the assessment.

If the Registrar accepts the application:

  • both the carer who made the application and the parent liable to pay child support must be advised in writing (section 151C(4)), and
  • both parties must be advised that, if aggrieved by the decision, they may object to the particulars of the assessment (section 151C(5)).

Suspension determination

An application made for a child support assessment to continue beyond a child's 18th birthday must be accepted by the Registrar if, among other things, the Registrar is satisfied that a suspension determination under CSA Act section 150F provides that child support is not payable in respect of the day before the child turns 18 (CSA Act section 151C(2)(b)(ia)). However, there must be a carer entitled to child support at the time the Registrar is making the decision whether to accept an application for a child support assessment to continue beyond a child's 18th birthday. This means:

  • where an application has been made by the carer entitled to child support, and a suspension period has not commenced, a decision could still be made by the Registrar to accept the application for a child support assessment to continue beyond a child's 18th birthday
  • where an application has been made on a day and a suspension period is later determined to apply on that day, and the Registrar has not yet made a decision on the application, the Registrar cannot accept the application for a child support assessment to continue beyond a child's 18th birthday as there was no carer entitled to child support on that day.

See 2.10.4 for information on suspension determinations.

Other options if assessment is not extended

Change of assessment

If an administrative assessment for a child is not extended past the child's 18th birthday, either parent may make an application to change the assessment where, in the special circumstances of the case, their capacity to support the other child/children of the assessment is significantly reduced by their duty to maintain the adult child over 18 years of age (2.6.15).

Adult child maintenance orders

A court with family law jurisdiction is able to deal with applications for child maintenance from parents or carers not eligible for a child support assessment. This includes an order for further maintenance of a child over the age of 18 if this is necessary to enable the child to complete their education or because the child has a physical or mental disability. If a court has ordered the payer to pay child support for a child over 18 it will not be necessary to apply for the assessment for that child to continue (see 3.1.3 for more information about child maintenance orders including whether the orders can be registered with the Registrar for collection).

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