Know what every night of care is worth before you agree to a care plan

Child support is worked out with an eight step formula. Each parent's adjusted taxable income has a self-support amount of $31,046 taken off, plus an amount for any other children they support. The two results are added together, and each parent's share is their income percentage. Nights of care become a care percentage, which a table turns into a cost percentage. Income percentage minus cost percentage decides who pays and how much.

Usually, yes. Equal care gives both parents a 50% cost percentage, but it does not make their incomes equal, so the parent with the higher child support income generally still pays. Nothing is payable only when both parents' child support incomes are also equal. The 50% band runs from 176 to 189 nights a year, and every night in that range gives the same answer.

No. A new partner's income is not used in a child support assessment, on either side, at any income. Only the two parents' own adjusted taxable incomes count, and a non-parent carer's income is not counted either. A partner's income can affect Family Tax Benefit, which is a separate payment with separate rules. That is usually where the confusion starts.

Shared care starts at 128 nights a year, which is 35% of the nights, or about five nights a fortnight. At 128 nights the cost percentage moves from a flat 24% to 25%. From there, each extra percentage point of care is worth two points of cost percentage. The biggest single step is much lower down, at 52 nights a year.

It can be worth nothing at all or thousands of dollars a year, depending on which side of a step you are on. The care table has seven bands and five of them are flat, so between 52 and 127 nights a year an extra night is worth nothing. Then one more night crosses a line. The steps fall at 52, 128, 176, 190, 238 and 314 nights a year.

The minimum annual rate is $551 a case, and it only applies where the paying parent has less than regular care (under 14%) of every child in the case. A separate fixed annual rate of $1,825 a child applies to a paying parent whose adjusted taxable income is under $26,720, who received no income support payment in the last relevant year, and who has less than shared care. Both can be reduced on application.

The self-support amount is $31,046 a year for the child support period starting 1 January 2026. It is one third of annualised male total average weekly earnings. It is taken off both parents' adjusted taxable incomes before anything is shared out, whatever they earn and wherever they live, and it is indexed every 1 January.

A change of assessment is an application to have the formula set aside for your case because it gives an unfair result, and applying costs nothing. The law lists ten reasons in section 117(2), and you have to make out at least one of them with evidence. Either parent can apply. Services Australia decides it rather than a court, and the other parent gets to respond.

Section 117(2) sets out ten: the high cost of spending time with a child; the child's special needs; an education both parents intended; the child's own income or property; money or property already transferred for the child; child care costs for a child under 12; necessary expenses that reduce capacity to pay; income, earning capacity or resources the assessment misses; a duty to maintain another child or person; and a resident child.

Yes, if your income has dropped by at least 15%, you can lodge an income estimate. It takes effect from the day you lodge it and never before, so every week of delay is a week assessed on the old figure. A drop of less than 15% is not enough on its own, and would need one of the ten change of assessment reasons instead.

You have 28 days. Report a care change within 28 days and the new level generally applies from the day care actually changed. If you report it later and your care went up, the change usually applies only from the day you told them. If your care went down, it still applies from when it happened.

Yes. A grandparent or other non-parent carer can apply for child support if they care for the child at least 128 nights a year and are not the partner of either parent. The carer applies for child support from both parents, not just one. The carer's own income is never counted in the assessment, and neither is their partner's.

No. Salary sacrificing into super lowers your tax but does nothing to your child support. The assessment uses adjusted taxable income, which adds four things back onto taxable income: reportable fringe benefits, reportable super contributions, net investment losses and foreign income. Negative gearing works the same way, with the loss added straight back. Both parents' figures are printed on the assessment notice.

Yes, through a change of assessment under reason 3, but only where both parents intended the child to go to that school. The test is what both parents planned, not what one of them now wants, and enrolment forms signed by both parents are the strongest evidence there is. The parent paying the fees is credited with them, and applying costs nothing.

No, and nothing here pretends to be. Services Australia runs the child support scheme and is the only body that can tell you what your assessment actually is. This calculator applies the published rules to the figures you type in, shows every step, and prices options a quick estimate cannot show.