How Much Child Support Will I Pay on $100k?
If you make $100k in Australia, the amount of child support you pay could technically range anywhere from $0 up to a bounded maximum in 2026 of $20,120 per year. That range varies according to how much care you provide, the income of the other parent, and the number and ages of the children.
A realistic range for most payers is between $7,686 per year for one child and $12,457 for two children. These scenarios assume you have regular care of 2–4 overnights each fortnight and the other parent has a taxable income of $50,000 annually.
A Better Answer Than “It Depends”
The amount of child support you pay on $100k depends on the details of the case, particularly care levels, number and ages of children, and the other parent’s income. However, we can still identify both the technical limits and a realistic range for most parents.
Parents asking this question want a dollar guide, not a purely theoretical answer. The examples below show both the extreme outcomes and the typical ones.
You can also quickly estimate your payment using our child support calculator for Australia.
Disclaimer: This information is based on Australian law and is for general guidance only. Services Australia issues legally enforceable administrative assessments of child support.
How Child Support Is Calculated
Child support is calculated using a legislated formula administered by Services Australia. The formula takes into account each parent’s taxable income after allowing for the self-support amount, the number and ages of the children, and the level of care provided by each parent.
The result is an annual assessment that may be payable, nil, or in some cases payable in the opposite direction depending on relative income and care.
Care Levels Used in These Examples
Care is measured by the number of overnight stays per fortnight. Services Australia applies fixed administrative care bands, each of which has a defined effect on the assessment.
| Nights per fortnight | Administrative care level |
|---|---|
| 0–1 | Less than regular care |
| 2–4 | Regular care |
| 5–6 | Shared care |
| 7 | Equal care |
The examples below use less than regular care, regular care, and equal care to illustrate how assessments change at different care levels.
Scenario 1: Technical Upper Bound ($20,120)
The upper bound occurs where you have less than regular care, the other parent’s income is below the self-support amount, and there are at least three children.
In 2026, the highest standard administrative assessment for a $100k income is $20,120 annually.
Inputs
- Your taxable income: $100,000
- Other parent’s income: $0 to $31,046
- Children: 3 or more children of mixed ages
- Your care: 0–1 nights per fortnight
Result
- Status: Pay
- Annual child support: $20,120
- Monthly payment: $1,677
Scenario 2: Technical Lower Bound ($0)
The technical lower bound is zero. This occurs when care is shared equally and both parents have similar incomes.
Inputs
- Your taxable income: $100,000
- Other parent’s income: $100,000
- Children: Any number > 0
- Your care: 7 nights per fortnight
Result
- Status: Nil
- Annual child support: $0
- Monthly payment: $0
Scenario 3: Realistic Lower Anchor ($7,686)
A realistic lower outcome occurs with one child and regular but minority care.
For a $100k income, this is about $7,686 annually when the other parent earns $50k.
Inputs
- Your taxable income: $100,000
- Other parent’s income: $50,000
- Children: 1 child aged 0–12
- Your care: 2–4 nights per fortnight
Result
- Status: Pay
- Annual child support: $7,686
- Monthly payment: $641
The $50,000 assumption reflects a typical moderate income for the primary carer. In regular-care scenarios, the assessment is not highly sensitive to moderate changes in the primary carer’s income.
Scenario 4: Realistic Upper Anchor ($12,457)
A realistic upper outcome occurs where there are two children and regular care continues.
For a $100k income, this is about $12,457 annually when the other parent earns $50k.
Inputs
- Your taxable income: $100,000
- Other parent’s income: $50,000
- Children: 2 children of mixed ages
- Your care: 2–4 nights per fortnight
Result
- Status: Pay
- Annual child support: $12,457
- Monthly payment: $1,038
This defines the upper end of the realistic range for parents on $100k who still have regular care. Most child support cases involve one or two children.
