# Basic formula

This formula is for parents with only one child support assessment.

Read about parents with 2 or more assessments.

This page is for general information. To calculate an estimate of your child support payments you can use our child support estimator.

## Basic 8 step formula

StepWhat we doThis step is about
1. Work out each parentâ€™s child support income

We calculate each parentâ€™s child support income. This is a parentâ€™s adjusted taxable income minus a self-support amount and any relevant dependant allowance. For more information about relevant dependant allowances, go to child support assessments and second families.

A parent may be able to estimate their income. Read more about income used in calculating a child support assessment.

Income
2. Work out the parentsâ€™ combined incomeWe add both parentsâ€™ incomes to work out a combined child support income.Income
3. Work out each parentâ€™s income percentageWe work out each parentâ€™s income percentage by dividing each income by the combined total.Income
4. Work out each parentâ€™s percentage of careWe calculate each parentâ€™s percentage of care.Care
5. Work out each parentâ€™s cost percentageWe work out each parentâ€™s cost percentage using the Care and Cost table.Care
6. Work out each parentâ€™s child support percentage

We subtract the cost percentage from the income percentage for each parent. We call this the child support percentage. The result will determine if a parent pays or gets child support.

If itâ€™s a negative percentage, we assess that parent as the parent to get child support. This is because their share of costs for the child is more than the amount of care they provide.

If itâ€™s a positive percentage, we assess that parent as the parent to pay child support. This is because theyâ€™re not meeting their share of the costs for the child directly through care.

If you have different care arrangements for various children, you might have different child support percentages for each child.

We go on to steps 7 and 8 using only the positive child support percentage.

Child support percentage
7. Work out the costs of childrenWe work out the costs for each child based on the parentsâ€™ combined total income. We do this by using the Costs of Children table.Costs of children
8. Work out the child support amountWe work out the total amount of child support payable. We do this by multiplying the positive child support percentage by the costs of the child. If we assess both parents are to pay each other, we offset these amounts before arriving at the final figure. This final figure is the amount the paying parent needs to pay the other parent.Child support to pay

## Care and cost table

Your care percentage is the amount of time you spend with the child. This helps us to work out your cost percentage.

Your cost percentage is your share of the childâ€™s costs that you meet directly through care.

Care percentageEqual to number of nights a yearEqual to number of nights a fortnightCare levelCost percentage
0-13%0-511Less than regular care0%
14-34%52-1272-4Regular care24%
35-47%128-1755-6Shared care25% plus 2% for every percentage point over 35% of care
48-52%176-1897Shared care50%
53-65%190-2378-9Shared care51% plus 2% for every percentage point over 53% of care
66-86%238-31310-12Primary care76%
87-100%314-36513-14More than primary care100%

## Costs of children

The Costs of Children tables recognise that raising children costs different amounts for different people. Because of this we work out your childrenâ€™s costs based on all of the following. The:

### About the tables

Steps 1 and 2 of the basic 8 step formula explain what combined child support income is.

Under the formula, we deduct an amount for each parent to support themselves. We calculate the costs of raising children according to the remaining combined child support income of both parents. We divide the costs between the parents according to their share of the combined income.

The Costs of Children table represents net costs after Family Tax Benefit. All the figures in these tables are for child support periods starting in 2024.

Read about Costs of Children for past years in the Child Support Guide on the Department of Social Services website.

### Children aged 12 and under

Parents combined child support incomeCost of 1 childCost of 2 childrenCost of 3 or more children
\$0 to \$42,69517c for each \$124c for each \$127c 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 donâ€™t go up past this cap

\$26,043\$40,561\$51,234

Read more about parents combined child support income.

### Children aged 13 or older

Combined child support income for one yearCost of 1 childCost of 2 childrenCost of 3 or more children
\$0 to \$42,69523c for each \$129c for each \$132c 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 donâ€™t go up past this cap

\$32,448\$49,099\$60,626

Read more about parents combined child support income.

### Children of mixed ages

Combined Child Support income for one yearCost of 2 childrenCost of 3 or more children
\$0 to \$42,69526.5c for each \$129.5c 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 donâ€™t go up past this cap

\$44,829\$55,930

Read more about parents combined child support income.

Page last updated: 3 January 2024.
QC 30381