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Example - Calculating the rate of child support

Jack and Jill separate. They have one child, Jenny, aged 3 years, who spends 285 nights of the year with Jill, and 80 nights with Jack. Jack earns $83,523, and Jill earns $43,523. They have no other children.

1. Work out each parent’s Adjusted Taxable Income.

Jack - $83523 Jill - $43523

2. Subtract the self-support amount.

Jack - $83523 Jill - $43,523

$23523 $23523

$60000 $20000

3. Subtract a further amount if either parent has a relevant dependent child or pays child support for another child or children. This is not applicable in this example.

4. Calculate the Combined Child Support Income.

$60000 + $20000 = $80000

5. Consult the Cost of Children table to determine the cost of a 3 year old child in a family with a Combined Child Support Income of $80000.

$11291 plus 12cents for every $1 of income above $70569 ($80000 - $70569 = $9431 x .12c = $1131.72)

$11291 + $1131.72 = $12423 per year

5. Calculate each parent’s Income Percentage, which is their share of the costs of the child based on the Child Support Income alone.

Jack 60000 /80000 x 100 = 75%

Jill 20000 /80000 x 100 = 25%

6. Work out the Cost Percentage based on the level of care each parent provides for the child.

Jack 80 nights Regular Care Cost percentage 24%

Jill 285 nights Primary Care Cost percentage 76%

7. Calculate the Child Support Percentage by subtracting the Cost Percentage from the Income Percentage. This adjustment recognizes that some or all of Jenny’s costs are being met through the care that is provided by Jack and Jill.

Jack 75% - 24% = 51% Jack will have to pay child support to Jill.

Jill 25% - 76% = -51%

8. Work out the amount of child support payable by multiplying the cost of the child by the Child Support Percentage.

Jack $12423 x 51% = $6336 per year

The Department of Human Services – Child Support has a child support Estimator on their website. Parents may find it a useful tool in less complex cases:

Example - Calculating the rate of child support  :  Last Revised: Mon Oct 27th 2014
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