Child Support Calculator in Australia by Ferrall and Co.
Understanding child support amounts is crucial for families. Child support assessments in Australia are managed by Services Australia using a legislative formula. We provide tools and legal assistance to help you understand how the formula may apply to your circumstances.
- Child Support Calculator Estimator
Calculate your estimated contribution based on current legislative formulas.
Enter Parent 1's income and any other relevant dependent children living with them.
Enter Parent 2's income and any other relevant dependent children living with them.
Enter each child's age group and nights with Parent 1. Parent 2 receives the remaining nights.
| Child | Age | Parent 1 care | Parent 2 care | Estimated amount |
|---|
Ferrall & Co. Lawyers can help you understand how child support may apply alongside parenting and other family law matters.
Contact Ferrall & Co.What counts as income?
For child support purposes, your “adjusted taxable income” is used. This typically includes the following components.
- Taxable Income
Salary, wages, and business profits earned during the financial year.
- Dividends
Profits distributed from company shares or investment holdings.
- Foreign Income
Income earned outside of Australia not already taxed domestically.
- Fringe Benefits
Employer provided benefits like company cars or subsidized health insurance.
- Super Contributions
Reportable superannuation contributions made by you or your employer.
Basic child support assessment process
Services Australia uses an 8-step formula to calculate the assessment. The basic steps are:
Determine Combined Income
Combine both parents’ child support income after deductions.
Apply Income Percentage
Determine each parent’s share of the combined total income.
Subtract Cost Percentage
Offset income percentage by the percentage of care provided by each parent.
- Self-support deduction
A fixed amount is subtracted from each parent’s income to cover basic living costs before child support is calculated. The annualised MTAWE in 2026 is $93,137. This means that the self-support deduction in 2026 is $31,046. Figures current as at July 2026.
Determining child support income percentage
Your income percentage is calculated by dividing your individual child support income by the combined total. This represents your relative capacity to contribute to the child’s costs. This process involves calculating each parent’s adjusted taxable income, subtracting the self-support deduction, and then finding each parent’s share of the combined pool.
How care and nights change the arrangement
The number of nights a child spends with you determines your care category and “cost percentage”.
Below regular
Nights: 0 – 51
Care: 0% to <14%
Regular
Nights: 52 – 127
Care: 14% to <35%
Shared
Nights: 128 – 237
Care: 35% to 65%
Primary
Nights: 238 – 313
Care: >65% to 86%
Above primary
Nights: 314 – 365
Care: >86% to 100%
The costs of children and the 2026 figures
The basic cost of a child is determined by the “Costs of Children” table, which varies based on the combined income and ages of the children (children aged 12 and under, and children aged 13 and over). For 2026, the costs of the children do not increase once the combined child support income reaches $232,843. Income above the cap is still counted when each parent’s income percentage is worked out.
When the formula doesn't fit your situation
The standard formula may result in an unfair outcome in specific cases. You can apply for a “Change of Assessment” based on any of these 10 legislative reasons:
Special circumstances require detailed documentation and legal proof. Ferrall and Co. can assist with your application.
- 1. High cost to spend time with children (more than 5% of adjusted taxable income)
- 2. Children's special needs
- 3. High cost of education
- 4. Child has income/property
- 5. Benefit to child from money/property
- 6. High cost of child care (under 12)
- 7. Parent's high living expenses
- 8. Parent's income, property, financial resources or earning capacity
- 9. Legal duty to maintain another person or child
- 10. Responsibility to maintain a resident child
Making a child support agreement
Parents can choose to move away from the formula by entering into a Private Agreement. These are formal legal documents that must meet specific requirements.
Binding Agreements
A Binding Child Support Agreement (BCSA) provides the highest level of certainty. Can set any amount or method of payment, but has strict legal requirements.
Key Requirements:
- The parent receiving support needs at least 35% care of the child
- Both parties receive independent legal advice and each gets a legal certificate
- Generally ended by a new agreement or court order, though it can also end or be suspended if care changes or on a terminating event
Limited Agreements
A Limited Child Support Agreement is a more flexible option that doesn’t require formal legal advice to sign, though it is highly recommended.
Key Requirements:
- A Child Support assessment must already be in place
- Payment must be equal to or greater than the assessment
- Can be terminated by either party after 3 years
Ferrall and Co. Lawyers can help
Our family law team provides guidance on child support arrangements. We can help with:
- Understanding your assessment results
- Documentation for Change of Assessment
- Negotiating fair support arrangements
- Drafting and lodging a Binding Child Support Agreement (BCSA)
Child support is often one part of a broader discussion about your children. Ferrall and Co Lawyers can also assist with parenting agreements and consent orders to provide clarity on all aspects of your family’s future. Visit our Caloundra office to discuss your unique situation.
Legal Disclaimer
The information provided on this page and by the Child Support Calculator is for general informational purposes only and does not constitute legal or financial advice. The results are estimates based on standard formulas and may not reflect the actual assessment issued by Services Australia. Ferrall and Co. Lawyers does not guarantee the accuracy of calculations for specific individual circumstances. We strongly recommend seeking professional legal advice before making any formal agreements or financial decisions regarding child support.
Figures current as at July 2026.