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Parents with two or more child support assessments
The calculations for parents with two or more child support assessments are a little more involved, yet are still based on the basic formula.
If you pay or receive child support for two or more families, we deduct an amount — called the multi-case allowance — after we deduct the self-support amount and any relevant dependent child amount from your adjusted taxable income, to arrive at your child support income. We then go on to apply the basic formula.
The multi-case allowance recognises your responsibility for supporting your children in other child support cases.
Multi-case allowance and costs
The multi-case allowance for each child support child is the total of the multi-case costs for children in your other child support cases. We work out the multi-case cost for each child according to the age of the child and how much it would cost if all the children were living fulltime with you.
We calculate the multi-case cost of each child as if all the children were the same age as that child. Older children have a higher multi-case cost than younger children of the same parent.
To work out this cost, we:
- Work out the total number of your child support children
- Look up your income and the age of the child on the relevant cost of children table to find what all the children would cost if they were all the same age
- Divide this amount by the total number of child support children.
We follow this process for each child.
Multi-case cap
Where a paying parent has multiple cases, the formula uses a multi-case cap to determine the maximum amount of child support payable. The multi-case cap ensures you don’t pay more in child support than it would cost you if you had all your child support children living with you. To work out the multi-case cap, we take the multi-case cost of the child adjusted for any care you have of the child.
Example: Ari
Ari has three children who live with their mothers: Tara, 14, and Maya, 9 live with their mother, Jenny, and Aron, 5, lives with his mother, Fay. Ari has no level of care of the three children, and he has no relevant dependent children.
Ari's adjusted taxable income is $40,000. We deduct $18,252* (the self-support amount), which gives a child support income of $21,748. This is the income we use to calculate the multi-case cost of his three children.
Even though the child support worked out in each of Ari's cases will acknowledge his obligation to support all of his children, each case is worked out separately.
Multi-case costs
For Tara:
- Because Ari has three children, the multi-case cost for Tara is based on the cost of three children aged 14, using Ari's child support income of $21,748. We divide the cost by three to get Tara's multi-case cost.
- Table B: Costs of children 2008 shows that the cost of three older children at this child support income is $6,959 ($21,748 multiplied by 32 cents).
- Divide $6,959 by three gives a multi-case cost for Tara of $2,320.
For Maya:
- Because Ari has three children, the multi-case cost of Maya is based on the cost of three children aged 9, using Ari's child support income of $21,748. We divide the cost by three to get Maya's multi-case cost.
- Table A: Costs of children 2008 shows that the cost of three younger children at this child support income is $5,872 ($21,748 multiplied by 27 cents).
- $5,872 divided by three gives a multi-case cost for Maya of $1,957.
For Aron:
- The multi-case cost for Aron is the same as the multi-case cost for Maya, as they are both aged under 13.
- Aron's multi-case cost is also $1,957.
Multi-case allowance
The multi-case allowance is the total of multi-case costs for children in other cases.
For Tara and Maya:
- Aron's multi-case cost is $1,957.
- Ari's multi-case allowance in the case for Tara and Maya is $1,957.
- We take Ari's adjusted taxable income of $40,000, deduct the self-support amount of $18,252 then we deduct $1,957 in multi-case allowance.
- Ari's child support income for this case is $19,791.
For Aron:
- Tara's multi-case cost is $2,320 and Maya's is $1,957, so Ari's multi-case allowance in the case for Aron is $4,277.
- We take Ari's adjusted taxable income of $40,000, deduct the self-support amount of $18,252* then we deduct $4,277 in multi-case allowance.
- Ari's child support income for this case is $17,471.
Multi-case cap
The multi-case cap is calculated for each child separately.
For Tara her multi-case cost is $2,320.
Because Ari has no care of Tara, the multi-case cap for Tara is $2,320. The same care and cost percentages apply as for other child support calculations.
If Ari had regular care (14–34 per cent) of Tara, he would be credited with meeting 24 per cent of her costs directly. So, the multi-case cap for Tara would be 76 per cent of $2,320—$1,763. If Ari had 50 per cent care of Tara, he would be credited with meeting 50 per cent of her costs directly. So, the multi-case cap would then be 50 per cent of $2,320—$1,160.
The same process is followed to calculate the multi-case cap for Maya and Aron.
Next steps
- Ari then goes to step two of the basic formula and follows the steps outlined to work out the child support payable for each case.
- Ari uses his child support income as worked out above, and calculates each child support case separately.
- The child support amount calculated is then compared to the multi-case cap amount — Ari will pay the lesser of these two amounts.
* The self-support amount for child support periods starting in 2008 is $18,252. This amount is indexed each year. You will be advised in writing when this amount changes.
