Separation and divorce brings many challenges, especially when there are children involved. The Australian child support system is designed to facilitate appropriate contributions from both parents towards their children’s everyday expenses. Set formulas are used to determine how much child support a person will pay, based on several key variables.

What is Child Support?

Child support is a financial obligation paid by one parent to the other, aimed at contributing to the everyday living expenses of their children following separation or divorce. Its core purpose is to ensure that children maintain a standard of living that closely resembles what they might have enjoyed had their family remained intact. This system underscores the principle that both parents bear equal responsibility for their children’s expenses and financial security.

In Australia, child support is predominantly governed by the Child Support (Assessment) Act 1989, alongside the Family Law Act 1975 (Cth) in some cases. These pieces of legislation establish the rules for assessing, collecting, and transferring child support payments, ensuring that the process is transparent, and considers the financial capacity of each parent. The Department of Human Services (DHS), through its Child Support Program, administers these laws, providing a structured approach to help parents manage their child support arrangements efficiently and equitably.

How Is Child Support Calculated?

To determine the child support amount, the DHS uses a child support assessment formula which examines the situation of both parents. There are six different formulas used to calculate the child support amount.

In most cases, the annual amount of child support will be calculated using Formula 1, the Basic Child Support Formula used for single child support assessments where only the parents provide care for the children and neither parent has another child support assessment case.

How to Calculate Your Child Support

Let’s look at how to calculate child support with an example of Bob and Mary’s child support costs for their 11 year old daughter. If we use the Basic Child Support Formula as provided by the Australian Government’s Guides to Policy, child support is calculated as follows:

1. Identify the child support income for each parent

Start by determining the child support income for each parent. You calculate this by looking at a parent’s taxable income and subtracting the amount each parent would need to support themselves individually. 

2. Calculate the combined child support incomes for a total child support income

Add both parent’s child support incomes together for a total.

3. Calculate each parent’s income percentage

Divide each parent’s child support income by the total child support income to get their income percentage.

4. Determine each parent’s percentage of care

This is the amount of time each parent spends caring for the child which influences the support calculation, with more significant care responsibilities potentially reducing the financial obligation. 

  • Below regular care: 0% to 13% of the time is equal to 0 to 51 nights a year or 0 to less than 2 nights fortnightly.
  • Regular care: 14% to 34% of the time is equal to 52 to 127 nights a year or 2 to 4 nights a fortnight.
  • Shared care: 35% to 64% of the time is equal to 128 to 237 nights a year or 5 to 9 nights a fortnight.
  • Primary care: 65% to 86% of the time is equal to 238 to 313 nights a year or 10 to 12 nights a fortnight.
  • More than primary care: 87% to 100% of the time is equal to more than 313 nights a year.  

5. Determine the cost percentage 

Based on the care percentage, use the chart to identify the extent to which each parent contributes to the child’s costs through direct care.

Care percentage

Equal to number of nights a year

Equal to number of nights a fortnight

Care level

Cost percentage

0-13%

0-51

1

Less than regular care

0%

14-34%

52-127

2-4

Regular care

24%

35-47%

128-175

5-6

Shared care

25% plus 2% for every percentage point over 35% of care

48-52%

176-189

7

Shared care

50%

53-65%

190-237

8-9

Shared care

51% plus 2% for every percentage point over 53% of care

66-86%

238-313

10-12

Primary care

76%

87-100%

314-365

13-14

More than primary care

100%

6. Calculate each parent’s child support percentage 

This step involves subtracting the cost percentage from the income percentage for each parent,  to calculate the child support percentage. This determines who pays and who receives child support. 

If the child support percentage is negative, this parent will receive child support. 

If the child support percentage is positive, this parent will pay child support.

There may be different arrangements for different children, therefore there may be different support percentages for each child.

*Steps 7 and 8 use only the positive child support percentage.

7. Work out the cost of each child

Work out the cost of each child based on the parents’ total combined child support income and by using the charts below:

Children aged 12 and under

Parents combined child support income

Cost of 1 child

Cost of 2 children

Cost of 3 or more children

$0 to $42,695

17c for each $1

24c for each $1

27c for each $1

$42,696 to $85,389

$7,258 plus 15c for each $1 over $42,695

$10,247 plus 23c for each $1 over $42,695

$11,528 plus 26c for each $1 over $42,695

$85,390 to $128,084

$13,662 plus 12c for each $1 over $85,389

$20,067 plus 20c for each $1 over $85,389

$22,628 plus 25c for each $1 over $85,389

$128,085 to $170,778

$18,785 plus 10c for each $1 over $128,084

$28,606 plus 18c for each $1 over $128,084

$33,302 plus 24c for each $1 over $128,084

$170,779 to $213,473

$23,054 plus 7c for each $1 over $170,778

$36,291 plus 10c for each $1 over $170,778

$43,549 plus 18c for each $1 over $170,778

Income over $213,473

Costs don’t go up past this cap

$26,043

$40,561

$51,234

Children aged 13 or older

Combined child support income for one year

Cost of 1 child

Cost of 2 children

Cost of 3 or more children

$0 to $42,695

23c for each $1

29c for each $1

32c for each $1

$42,696 to $85,389

$9,820 plus 22c for each $1 over $42,695

$12,382 plus 28c for each $1 over $42,695

$13,662 plus 31c for each $1 over $42,695

$85,390 to $128,084

$19,213 plus 12c for each $1 over $85,389

$24,336 plus 25c for each $1 over $85,389

$26,897 plus 30c for each $1 over $85,389

$128,085 to $170,778

$24,336 plus 10c for each $1 over $128,084

$35,010 plus 20c for each $1 over $128,084

$39,706 plus 29c for each $1 over $128,084

$170,779 to $213,473

$28,605 plus 9c for each $1 over $170,778

$43,549 plus 13c for each $1 over $170,778

$52,087 plus 20c for each $1 over $170,778

Income over $213,473

Costs don’t go up past this cap

$32,448

$49,099

$60,626

Children of mixed ages

Combined Child Support income for one year

Cost of 2 children

Cost of 3 or more children

$0 to $42,695

26.5c for each $1

29.5c for each $1

$42,696 to $85,389

$11,314 plus 25.5c for each $1 over $42,695

$12,595 plus 28.5c for each $1 over $42,695

$85,390 to $128,084

$22,201 plus 22.5c for each $1 over $85,389

$24,763 plus 27.5c for each $1 over $85,389

$128,085 to $170,778

$31,807 plus 19c for each $1 over $128,084

$36,504 plus 26.5c for each $1 over $128,084

$170,779 to $213,473

$39,919 plus 11.5c for each $1 over $170,778

$47,818 plus 19c for each $1 over $170,778

Income over $213,473

Costs don’t go up past this cap

$44,829

$55,930

8. Calculate child support amount

Multiply the positive child support percentage by the cost of the child to determine the annual rate of child support that will be paid.

These steps are designed to ensure that child support payments are equitable and reflect the financial capabilities of each parent, the needs of the child, and the practicalities of the care arrangements.

Example

Now, let’s look at an example. 

Bob and Mary are calculating their child support payments. Bob makes $98,463 per year, and Mary makes $58,463. Now let’s go through the formula step by step. 

1. Identify the child support income for each parent.

The self-support amount is defined as taxable income – one third of the MTAWE (Male Total Average Weekly Earnings). The self-support amount will be the same for both parents. In 2024, the MTAWE is $85,389, meaning the self-support amount is $85,389/3=$28,463. You can find out the MTAWE and self-support amount for a given year here

 

Bob

Mary

Taxable Income

$98,463

$58,463

Self-support amount

$28,463

$28,463

Child support income (taxable income – self-support amount)

$98,463 – $28,463 

=$70,000

$58,463 – $28,463 

=$30,000

So Bob’s child support income is $70,000 and Mary’s is $30,000

2. Calculate the combined child support incomes for a total child support income

This is very simple, we simply add each of their child support incomes. 

$70,000 + $30,000 = $100,000

3. Calculate each parent’s income percentage

For this, we divide each parent’s child support income by the combined child support incomes.

So, for Bob this would be: 

$70,000 / 100,000 x 100 = 70% 

And for Mary it would be: 

$30,000 / 100,000 x 100 = 30%

4. Determine each parent’s percentage of care

Bob takes care of the child for 3 nights every fortnight, with Mary taking charge for the other 11. This means Bob is a regular carer and Mary is a primary carer. 

5. Determine the cost percentage.

Using the table above, we can see that Bob’s cost percentage is 24% and Mary’s is 76%. 

6. Calculate each parent’s child support percentage

So for this we subtract the cost percentage from the income percentage. 

Bob: 70% – 24% = 46%

Mary: 30% – 76%= -46%

As Mary’s child support percentage is negative, she will be the one receiving child support. 

7. Work out the cost of each child

Bob and Mary only have one child, who is 9 years old. As their combined child support income is $100,000, they sit in the $85,390 to $128,084 bracket, as seen in the relevant table above. This means the cost of their child is calculated as $13,662 plus 12c for each $1 their combined child support income is over $85,389

So, we’d calculate as follows:

$100,000 – $85,389 = $14,611 

$14,611 x $0.12 = $1,753.32

$13,662 + $1753.32 = $15,415 (rounded to nearest dollar)

This means that the cost of Bob and Mary’s child is $15,415 per year. 

8. Calculate child support amount

We’re almost there! Now we just need to multiply the cost of the child by Bob’s child support percentage as he’ll be the one paying. 

So this is $15,415 x 46% = $7,091 (rounded to the nearest dollar). This means Bob has to pay $7,091 dollars in child support to Mary each year, which works out to roughly $136 dollars per week. 

For the most current information on minimum and maximum child support payments, including any conditions that might apply, parents should refer directly to Services Australia. This resource provides up-to-date guidelines and tools to help parents understand their obligations and entitlements within Australia’s child support framework. The above is some general information only and is subject to change.

Looking to Understand Child Support Better?

Daykin Family Law offers specialised guidance to parents seeking to establish, adjust, or understand child support agreements. Our team of child support lawyers is dedicated to ensuring that your child support arrangements are appropriate, compliant, and structured with the best interests of your child at heart. For personalised advice that aligns with the highest standards of Australian family law, contact Daykin Family Law today. Let us help you secure a stable financial future for your children.