Child Support Payments

Child support payments are the amounts transferred between separated parents to help cover the cost of raising children. The payment depends on each parent’s income and how much care they provide.

Amounts can be low in some cases, but payments of $10,000 to $20,000 per year are not unusual. You generally need a child support calculator to accurately estimate the amount payable.

Definition

Child support is a payment that one parent makes to the other parent, after separation, to contribute towards the costs of raising a child. It recognises the principle of children being financially supported by both of their parents.

Definition source: Guides to Social Policy Law, Child Support Guide, Version 4.97, released 20 March 2026, Child support.

The child support formula

Child support payments are calculated using a formula that compares each parent’s share of income with the share of costs they already meet through care. The result is a percentage that determines who pays and how much.

Formula
Child support payment = (Income % − Cost %) × Costs of children

Income percentage is a parent’s share of the combined income of the parents. Cost percentage is the share of costs recognised through daily care. The costs of children are set using national tables based on combined income, number of children, and ages.

When a parent’s income share exceeds their cost share, they pay child support. The final figure is converted into a periodic amount, usually a monthly payment.

Example

One parent earns $100,000 and has the child for 3 nights a fortnight (about 21% care). The other parent earns $60,000 and has most of the care. The higher-income parent is contributing less through care than their share of income, so they pay child support.

Using the formula, the assessed amount is about $9,996 per year, which works out to roughly $833 per month. This reflects both the income gap and the relatively low level of care for the paying parent.

What drives the amount
Income difference + care difference → payment size

If the same parent increased their care, the cost percentage would rise and the payment would fall. If incomes moved closer together, the payment would also reduce. The formula adjusts the amount to reflect both financial capacity and time spent caring for the child.

Assessment

Illustration of a separated family where a mother and child walk together while a man holds a money bag and another man stands observing in a park setting

Most child support payments are set through an administrative assessment by Services Australia. The amount payable is worked out using a national formula. The formula uses each parent’s income, the care percentage for each parent, and the number and ages of children.

This formula assessment is the default pathway when a parent applies for child support. Services Australia determines who pays and how much, then issues an assessment notice showing the annual and periodic amounts.

Different amounts can apply under a binding child support agreement, a limited child support agreement, or a court order. These are formal legal arrangements. The formula assessment remains the standard reference point in most cases.

Collection methods

After an assessment is made, payments are handled under either Agency Collect or Private Collect. This determines whether Services Australia manages the money or whether parents transfer payments directly.

Agency Collect is the default when the receiving parent applies for child support, which is the most common situation. Services Australia collects payments from the payer, transfers them to the receiving parent, and takes responsibility for monitoring and enforcement.

Private Collect is the default when the paying parent applies. The payer transfers the assessed amount directly to the other parent. Services Australia still sets the amount but does not handle the payments.

Collection pathway
Assessment → Agency Collect or Private Collect → payment transfer

The receiving parent can move the case into or out of Agency Collect at any time. Moving into Agency Collect brings Services Australia into the process to track payments and enforce any unpaid amounts.

In most cases, the payer makes the payment themselves online, usually monthly. Services Australia can also issue a Child Support Deduction Order to an employer, requiring payments to be deducted directly from wages. If the correct amount is not paid, the unpaid portion can be recorded and pursued as a child support debt.

Articles on child support payments

Analytical and perspective-based posts on payments in Australia.

  • Child Support Agency Contact

    The Child Support Agency (CSA) in Australia is just part of Services Australia. You can contact CSA by phone, online or by visiting a centre.