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2.4.9.20 Formula 4 - multiple child support cases with a non-parent carer

Context

Formula 4 is used to work out the annual rate (1.1.A.70) of child support (1.1.C.60) payable for a child when one or both of the parents (1.1.P.10) have at least one other case, and one or more non-parent carers has at least 35% care (1.1.C.10) of a child.

Act reference: CSA Act section 7B-'eligible carer', section 36 Formula 2: Working out annual rates …, section 37 Formula 3: Method statement …, section 38 Formula 4: Working out annual rates …, section 41 Working out parent’s child support income, section 42 Working out parents’ combined child support income, section 46 Working out parent’s relevant dependent child amount, section 47 Working out multi case allowances, section 48 Simplified outline, section 55A to section 55E Working out other elements for the formulas, section 55HA Working out the costs of the child …, section 156 Rounding of amounts

Formula 4

StepActionMore detail
1

Follow steps 1 to 6 of Formula 1 – the basic formula (1.1.B.10)

  • Step 1 - Work out each parent's child support income (1.1.C.120)

    Where a parent has more than one child support case (1.1.C.80), their child support income needs to be calculated separately for each case, as the parent's ATI (1.1.A.20) and multi-case allowance (1.1.M.30) may differ across their child support cases.

  • Step 2 - Work out the parents' combined child support income (1.1.C.190)
  • Step 3 – Work out each parent’s income percentage (1.1.I.30)
  • Step 4 – Work out each parent’s percentage of care (1.1.P.70) for the child
  • Step 5 - Work out each parent’s cost percentage (1.1.C.200) for the child
  • Step 6 – Work out each parent’s child support percentage (1.1.C.140) for the child
2.4.7
2A

Work out the COTC (1.1.C.210) for the day, calculating the costs for older and younger children separately (section 55HA). This is the same approach to calculating multi-case costs (1.1.M.50) but uses combined child support income (1.1.C.190).

  • Identify the costs for the child for that CSP (1.1.C.150), based on the combined child support income of the parents
  • Identify the number of children in the child support case
  • Identify the ages of the child support children
  • In respect of each child support child:
    • Assume that all the child support children are of the same age as that child, and
    • Identify the item in the relevant column in the COTC Table that covers the number of child support children of that age

The COTC are the costs identified in the COTC Table divided by the number of child support children

-
2B

If the parent has a positive child support percentage from Step 1, work out the following rate

  • Parent’s child support percentage for the child for the day × COTC for the day
-
3Work out each parent’s multi-case cap (1.1.M.40) (if any) for the child for the day (see section 55E)-
Annual rate payable by parent
4

If the parent’s (the first parent’s) child support percentage is positive under Step 6 of Formula 1 (Step 1 of this method), the rate of child support payable by the first parent for the child is the lower of:

  • Step 2B child support payable,
  • Step 2 multi-case cap for the child (if any)
-
Annual rate payable only to non-parent carers
5

If:

  • The second parent’s child support percentage is also positive, or
  • The second parent’s child support percentage is nil or negative, and the second parent does not have at least shared care (1.1.S.40) of the child,

then subject to section 40B, the first parent must pay the annual rate of child support that is payable by the first parent for the child to the non-parent carer/s child support in accordance with section 40A which is

Divide costs of the child for the day by Total of parent’s and non-parent carer’s cost percentages for the child for the day then multiply by Total rate to which parent and non-parent carers are entitled to be paid for the day 		-
Annual rate payable to parent and non-parent carer
6

If:

  • the second parent’s child support percentage is negative, and
  • the second parent has at least shared care of the child during the relevant care period,

then, subject to section 40B, the first parent must pay the annual rate of child support that is payable by the first parent for the child under Step 4 (subsection 38(4)) to the second parent and the non-parent carer as follows

Divide costs of the child for the day by Total of parent’s and non-parent carer’s cost percentages for the child for the day then multiply by Total rate to which parent and non-parent carers are entitled to be paid for the day 		-

Example: Using 2024 rates

In case 1, Aliya (ATI of $45,000) and Edmund (ATI of $70,000) have 2 children, Kristina aged 14 and Harriette aged 10. In case 2, Aliya has shared care of Claudia, aged 7. Aliya also has another child Louisa, aged 4, with her new partner.

Edmund has sole (100%) care of Kristina but Harriette lives full time with a grandparent Ali. Ali has made an application under section 25A for a child support assessment (1.1.C.70).

Case 1 (with non-parent carer)

Step 1 – calculate child support income

 AliyaEdmund
ATI$45,000$70,000
Self-support amount (1.1.S.20)$28,463$28,463
Relevant dependent child amount (1.1.R.60)Child support income = $16,537 ($45,000 − $28,463)
COTC = $2,811 ($16,537 × 17%)		Not applicable
Multi-case costs / multi-case allowance
Kristina aged 14

Child support income = $13,726 ($45,000 − $28,463 − $2,811)
COTC = $1,464

  • ($13,726 × 32% = $4,392)
  • $4,392 ÷ 3
Not applicable
Harriette aged 10

Child support income = $13,726 ($45,000 − $28,463 − $2,811)
COTC = $1,235

  • ($13,726 × 27% = $3,706)
  • $3,706 ÷ 3

Child support income = $41,537 ($70,000 − $28,463)
COTC = $4,984

  • ($41,537 × 24% = $9,969)
  • $9,969 ÷ 2
Claudia aged 5

Child support income = $13,726 ($45,000 − $28,463 − $2,811)
COTC = $1,235

  • ($13,726 × 27% = $3,706)
  • $3,706 ÷ 3
Not applicable
Multi-case allowance$1,235 (Claudia’s multi-case costs-
Child support income

$12,490

  • $45,000, less
  • $28,463, less
  • $2,811, less
  • $1,235

$41,537

  • $70,000, less
  • $28,463

Step 2 and 3 of Formula 1 – combined child support income and income percentage

 AliyaEdmund
Step 2 – combined child support income$54,027 ($12,490 + $41,537)
Step 3 - calculate income percentage23.12%76.88%

Step 4 and 5 of Formula 1 – percentage of care and cost percentage

 AliyaEdmundGrandparent - Ali
Step 4 – Calculate percentage of care for each child
Kristina0% (0 ÷ 365 nights)100% (365 ÷ 365 nights)0% (0 ÷ 365 nights)
Harriette0% (0 ÷ 365 nights)0% (0 ÷ 365 nights)100% (365 ÷ 365 nights)
Step 5 – Calculate cost percentage for each child
Kristina0%100%Not applicable
Harriette0%0%Not applicable

Step 6 of Formula 1 – child support percentage

 AliyaEdmundGrandparent - Ali
Kristina23.12%−23.12%Not applicable
Harriette23.12%76.88%Not applicable

Step 1A - work out COTC for the day under section 55HA

Kristina
  • Combined child support income = $54,028
  • Costs based on combined child support income = $15,555
  • Costs for the child = $7,778 ($15,555 ÷ 2 children in case)
Harriette
  • Combined child support income = $54,028
  • Costs based on combined child support income = $12,853
  • Costs for the child = $6,427 ($12,853 ÷ 2 children in case)

Step 1B - work out how much child support is payable for each child

 AliyaEdmund
Kristina$1,798 ($7,778 × 23.12%)Nil
Harriette$1,486 ($6,427 × 23.12%$,4,941 ($6,427 × 76.88%)

Step 2 - work out the multi-case cap (multi-case costs − (100% − cost percentage))

 AliyaEdmund
Kristina$1,464 ($1,464 × (100% − 0%)Nil
Harriette$1,235 ($1,235 × (100% − 0%)$4,984 ($4,984 − (100% − 0%))

Step 3 - calculate child support payable

 AliyaEdmund
Kristina

$1,464 (multi-case cap is less than child support $1,798)

Payable to Edmund

Nil
Harriette

$1,235 (multi-case cap is less than child support $1,235)

Payable to Ali

$4,941 (child support is less than multi-case cap $4,984)

Payable to Ali

Child support payable

Aliya is assessed to pay $1,464 to Edmund for Kristina and $1,235 to Ali for Harriette.

Edmund is assessed to pay $4,984 to Ali for Harriette.

A non-parent carer is not entitled to be paid child support they have applied under section 25A (section 40B). If more than one non-parent carer is entitled to receive child support from a parent or both parents, then their share of the entitlement is determined in accordance with section 40A. See Formula 2 (2.4.8) for information about the calculations required when child support is payable to more than one person.

Different rules apply if the MAR (1.1.M.20) of child support is payable to more than one person. See 2.4.12 for details of the rules that apply, which depend upon the level of care provided by the carer.

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