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can someone please explain how 2 CSA assessments work?

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trying to figure out what is best for our situtation housemates vs 2 households?

My ex partner and i have recently separated and we still havent decided how things will work out for our son. We are definately capable of living together as housemates and neither of us have a problem with doing this but at the end of the day it needs to benefit both of us. I remain at home to care for our son and ive not been having an easy time of finding a job (i think mostly because i dont have any references or recent experience). I do not currently recieve any centrelink payments as my ex partners income is too high and as we havent yet organised ourselves i havent informed centrelink we are no longer partnered. I understand that if we continue living together even as housemates then i dont have anything to support our separation and i will not be eligable for parenting payments.

My ex partner has 2 other children from another relationship and is paying child support for those children as their mother is the primary carer. In addition to being ineligable for parenting payments, if we continue living together my ex will be paying the same amount in child support as he was before we separated. His current child support assessment includes a relevant dependant child cost that slightly reduces the amount he pays for his other children.

If my son and i were to move into another house then my ex would not have the relevant dependant child cost to reduce the amount he pays for his other children but as i understand it the amount of child support he would be required to pay for his other children would be reduced as he would be required to also pay child support for our son, which also would be a lesser amount as he pays child support for 2 other children?

So in one situation my income is reduced and in the other situation my ex partner has to pay more - The costs of individually maintaining a household would be a difficult task for both my ex and myself. Im trying to figure out how both situations would financially impact my ex and i seperately and which is the better option for our son and ourselves.

could someone please explain how CSA determine the amount my ex partner would be required to both the mother of his other children and myself. (note: the mother of his other children is receiving full parenting payment from centrelink and does not have any other income). 

please share any other advice you may have.. thanks everyone!!


Blue text = additional information provided at about 10:30 on 11/10/2011

You can ascertain the CSA amounts by using the advanced calculator that is available from the home page (Note! the basic calculator, like the CSA's estimator, doesn't handle multi-case).

A multi-case situation can have two calculable scenarios. The first is if the multi-case allowance (MCA) applies, this is worked out in a similar way to the Relevant Dependant Child Amount (RDCA). That is the income (income is used throughout this post to mean adjusted taxable income) of the one parent that has the multi-case child/ren. However, the difference is that the RDCA is determined by applying the income against only the RDC children. When the MCA is calculated it is calculated based upon all the CS children and then divided by the number of CS children. The second scenario is what is termed as the multi-case cap, this is worked out by applying the level of care reduction to the multi-case cap and is meant to ensure that the parent pays no more than if the child were living with the parent.

I originally forgot to say that the multi-case cap is applied on a per child basis and caps the cost of that child at that amount.

The advanced calculator determines the type of case(s) based upon the relationships of the adults with the children. As such it's important that the relationship (the value in the drop down boxes; which can be, parent, other, non-parent carer, deceased parent, or parent abroad) between the children and the adults is correct. Even though the terminology is meant to make things straight-forward (additionally no simpler method could be envisaged), experience has shown that it's not necessarily that straight forward. Therefore, below is a guide to selecting the correct relationships for

To input your scenario, after the calculator appears add another parent and two extra children. Complete the income amounts of the adults. I'll assume that the first adult represents yourself, the second, represents your ex and the third represents the other parent of the MC children and that the first child is not the multi-case child. For the first child add the details and ensure that the third adult has a relationship of OTHER (the other two adults would have a relationship of PARENT), for the second and third child the relationship of the first adult should be OTHER (the other two adults would have a relationship of PARENT).

To change the scenario to the RDC scenario to do the comparison. You would change yourself (the second adult) from Parent to other (the calculator determines that you are not part of any case and also that the 2 children are n and this option is easier than deleting yourself as an adult if you want to do comparisons) and also change the level of care to 365 (i.e. the parent of an RDC will have 100% care).

If you want details such as the multi-case allowance and cap then check the "Show Calculations" check box.

Alternately here's the CSA's description regarding multi-case allowance:

Separated parents - Department of Human Services said
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 multicase allowance  after we deduct the selfsupport 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 multicase allowance recognises your responsibility for supporting your children in other child support cases.
Multicase allowance and costs

The multicase allowance for each child support child is the total of the multicase costs for children in your other child support cases. We work out the multicase 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.

Older children have a higher multicase 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.
Multicase cap

Where a paying parent has multiple cases, the formula uses a multicase cap to determine the maximum amount of child support payable. The multicase cap ensures you dont 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 multicase cap, we take the multicase 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 multicase cost for Tara is based on the cost of three children aged 14, using Aris child support income of $21,748. We divide the cost by three to get Taras multicase 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 multicase cost for Tara of $2,320.

For Maya:

    Because Ari has three children, the multicase cost of Maya is based on the cost of three children aged 9, using Aris child support income of $21,748. We divide the cost by three to get Mayas multicase 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 multicase cost for Maya of $1,957.

For Aron:

    The multicase cost for Aron is the same as the multicase cost for Maya, as they are both aged under 13.
    Arons multicase cost is also $1,957.

Multicase allowance

The multicase allowance is the total of multicase costs for children in other cases.

For Tara and Maya:

    Arons multicase cost is $1,957.
    Aris multicase 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.
    Aris child support income for this case is $19,791.

For Aron:

    Taras multicase cost is $2,320 and Mayas is $1,957, so Aris multicase 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.
    Aris child support income for this case is $17,471.

Multicase cap

The multicase cap is calculated for each child separately.

For Tara her multicase cost is $2,320.

Because Ari has no care of Tara, the multicase cap for Tara is $2,320. The same care and cost percentages apply as for other child support calculations.

If Ari had regular care (1434 per cent) of Tara, he would be credited with meeting 24 per cent of her costs directly. So, the multicase 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 multicase cap would then be 50 per cent of $2,320$1,160.

The same process is followed to calculate the multicase 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 multicase cap amount  Ari will pay the lesser of these two amounts.

* Figures, used in this example, such as the self-support amount, are indexed annually.

Here's a link to the respective page on the CSA's website. Parents with two or more child support assessments

The actual way the CSA determine it is either via an internal calculator, that I believe isn't widely known about, or to let cuba (cuba is the system/dsatabase that the CSA use) do it (oh and some use the advanced calculator on here). I think that you'd be lucky if you phoned up the CSA and asked how much the CS would be for a multi-case scenario and got an answer that told you the amount without having to be subject to the "pass the intray" game (intray is the terminology for work for a case).

As an example here's some calculations using your scenario, as I understand it, and assuming that the other parent (your ex) has an income of $70,000 and that all children are under 13 and that your ex has regular car of all children.

Current (your child is an RDC) CS would be $7468, the cost of the RDC is $8028 (this is deducted from the income and then that income used to determine the cost of the children and thus the resultant CS).

In the Multi-case scenario sing the same assumptions as above, the total CS paid is $9999 split as $6666 to the other recipient and $3333 to yourself.

The Multi-case allowance in your case is $8769 (thus reducing the combined child support income for your case by that amount) and the multi-case cap is $3333. As the cost of the child is $6713 and that the care reduction for regular care is 24%, the CS would be set at $5102. However the multi-case cap applies and thus the reduction/cap to $3333 (note! all of these values, with the exception of the CS without the cap, are available when you select th "show calculations" option and also click on the calculate button).

In this scenario, as the level of care and incomes are the same (I used an income of $0, which is no different than specifying PPS or income support amount), the other recipient basically gets double because there are two children.

Last edit: by MikeT

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