In Australia, a child support assessment and employer deductions work as two linked steps: Services Australia uses a formula based on both parents’ incomes, the cost of raising the children, and the care each parent provides to set a payment amount, and when the agency collects that payment it can issue a notice requiring the paying parent’s employer to withhold it directly from wages.1Services Australia. Basic Child Support Formula The scheme sits under the Child Support (Registration and Collection) Act 1988 and the Child Support (Assessment) Act 1989.2Department of Social Services. Child Support Scheme History
How the Assessment Amount Is Calculated
The formula is sometimes called the Income Shares model. Services Australia starts with each parent’s adjusted taxable income, which pulls in salary, investment returns, fringe benefits, and foreign income. From that figure, a self-support amount is subtracted for each parent, equal to one-third of the annualised Male Total Average Weekly Earnings. The idea is that a parent covers their own basic living costs before any child support obligation applies.1Services Australia. Basic Child Support Formula
What’s left of each parent’s income is pooled. Services Australia then looks up the Costs of Children tables, which estimate the typical cost of raising children at that combined income, taking into account the number of children and whether they are 12 and under or 13 and older. Each parent’s share of the combined income determines their share of those costs.
Care adjusts the final number. A parent with regular care (14% to less than 35% of nights, roughly 52 to 127 nights a year) gets a cost offset that reduces their liability. Shared care (35% or more of nights) attracts a larger offset.3Services Australia. How Your Percentage of Care Affects Your Child Support Payments If one parent’s cost share exceeds their income share after care is factored in, the other parent pays the difference.
The Minimum Annual Rate
Even very low-income parents have a baseline obligation. The Minimum Annual Rate applies per case and is capped at three times the rate across all of a parent’s cases.4Child Support Guide. Child Support Guide 2.3.4 – Minimum Annual Rate A parent whose income sits below the minimum assessment threshold can apply to have the rate reduced to nil.
Why the Collection Choice Matters for Employers
After the assessment is set, parents choose how payments move between them. The choice decides whether an employer ever hears about it.
With Child Support Collect, Services Australia tells the paying parent how and when to pay, receives the money, and transfers it to the receiving parent. If the paying parent falls behind, the agency pursues the arrears using its full enforcement toolkit, including wage deductions from employers.5Services Australia. Compare Your Child Support Collection Options
With Private Collect, the parents sort out payments between themselves and keep their own records. Services Australia stays out of the money flow unless something goes wrong, and even then it can only recover arrears going back three months in normal cases, or nine months in exceptional circumstances. Private Collect also caps the receiving parent’s Family Tax Benefit Part A at the base rate regardless of the assessed amount.6Services Australia. Private Collect Employers only come into the picture when collection runs through the agency.
How Employer Deductions Work
When Services Australia collects, the standard enforcement mechanism is wage withholding. An employer receives a Notice to Commence Child Support Deductions, and from that point the business is legally required to withhold the specified amount from the employee’s pay each cycle. The notice states a dollar amount or percentage. The employer has no discretion to vary it based on what the employee says about their situation or any private arrangement they claim exists with the other parent.
Withheld funds must reach Services Australia by the 7th day of the month after the deduction.7Services Australia. Notice to Commence Child Support Deductions for Employers Services Australia prefers that employers remit at the same frequency as the deduction (weekly, fortnightly, or monthly) rather than holding the money until the monthly deadline.8Services Australia. Payment Options for Child Support for Employers
When an employee with active deductions leaves, the employer must tell Services Australia promptly so the schedule stops. Employers should keep clear records of every deduction and every payment made.
The Protected Earnings Amount
Employers cannot deduct so much that the employee is left with nothing to live on. The Protected Earnings Amount is a floor on after-tax pay that must be preserved before any child support deduction is taken. For 2026, the weekly PEA is $544.88. On other pay cycles it is $1,089.76 fortnightly, $2,179.52 four-weekly, and $2,369.26 monthly.9Services Australia. Protected Earnings Amount When Deducting Child Support
If an employee’s after-tax pay in a given period would fall below the PEA once the full deduction is taken, the employer deducts only the amount that sits above the threshold and leaves the PEA untouched.10Department of Social Services. Child Support Guide 1.1.P.120 – Protected Earnings
Penalties for Getting It Wrong
Employers who fail to make required deductions, or who deduct but don’t remit, face a fine, imprisonment of up to 12 months, or both, along with an order to pay legal costs. Late remittance also attracts a penalty. Services Australia may waive the late-payment penalty where the employer can show the delay was beyond their control.11Services Australia. Your Legal Obligations as an Employer Under Child Support Legislation
If Your Income Has Changed
Assessments are normally built on income from the most recent tax return, which can be badly out of date if a parent has lost a job, cut back hours, or watched a business shrink. A parent in that position can lodge an income estimate so the assessment reflects what they’re earning now.12Child Support Guide. Child Support Guide 3.4.2 – Calculating an Income Estimate
A full-year estimate can be lodged before the financial year begins or on the first day of the year. A part-year estimate can be lodged at any point during the year, and requires both year-to-date income and the estimated income for the remaining period to 30 June. Services Australia annualises the part-year figure. To be accepted, an estimate generally needs to be less than 85% of the adjusted taxable income currently used in the assessment.
Once tax returns are lodged, Services Australia reconciles the estimate against actual income. Underestimating creates a lump-sum liability, so the figure should be realistic rather than hopeful.
Changing an Assessment for Special Circumstances
The formula doesn’t capture every situation. Either parent can apply for a Change of Assessment, but they must show one of ten specific reasons applies; being unhappy with the amount isn’t enough.13Services Australia. Changing Your Child Support Assessment in Special Circumstances The reasons cover things like high contact-travel costs that exceed 5% of adjusted taxable income, a child with special needs, an agreed private school, high child care costs for a child under 12, the child’s own financial resources, past property or money transfers for the child’s benefit, hidden earning capacity, necessary medical expenses, a legal duty to maintain another dependent, and supporting a resident child in defined circumstances.
Objecting to a Decision
If you believe Services Australia used wrong information, missed relevant facts, or misapplied the law, you can lodge a formal objection within 28 days of being notified of the decision. Parents living overseas in a reciprocating jurisdiction get 90 days.14Child Support Guide. Child Support Guide 10.2.4 – Can an Objection Decision Be Made
Once an objection is lodged, the Registrar sends a copy to the other parent and reconsiders the decision in light of any new information.15Child Support Guide. Child Support Guide 10.2.1 – Overview of Objections Both parents receive written notice of whether the objection is allowed, partly allowed, or disallowed. If you’re still unhappy, the Administrative Appeals Tribunal can conduct an external review.16Services Australia. Objections to Child Support Decisions
When Child Support Ends
Child support normally stops when the child turns 18. If the child is still in full-time secondary school at that point, the receiving parent can apply before the child turns 18 to extend the assessment to the end of the school year. A late application, after the child has already turned 18, is only accepted where exceptional circumstances outside the parent’s control prevented an earlier application.17Services Australia. Child Support When Your Child Turns 18 A court with family law jurisdiction can also order maintenance for a child over 18 in certain circumstances, and such orders can be registered with Services Australia for collection.