Yes, child support can increase as your child gets older. The amount is influenced by a range of factors including your income, the other parent’s income, the level of care you each provide, and notably, your child’s age.

Under family law principles, when your child turns 13, their cost of care is generally considered higher, which may result in a higher child support payment. However, this isn’t automatic and depends on how your case is assessed.

How Age Affects the Cost of Children

Child support calculations in Australia are based on a formula that considers the average costs of raising children.

These costs increase in age brackets, with a notable jump when a child turns 13.

This reflects the growing expenses as children move into high school, become more independent, and participate in more costly activities like sports, transport, and technology use.

Here’s how the age brackets generally work in terms of cost assumptions:

• Children aged 0–12 are considered to have lower costs.
• Children aged 13 and over are considered more expensive to raise.

If you’re the paying parent, and your child moves into the 13+ age bracket, your support payments may go up, depending on your financial situation and care arrangement.

Key Takeaway: Once your child turns 13, the assumed cost of care increases, which can lead to a higher child support amount.

How the Child Support Formula Works

The child support formula used in Australia takes into account:

• Both parents’ taxable incomes
• The number of children
• The percentage of care each parent provides
• The costs of children based on their age

Each parent’s share of the child’s costs is calculated proportionally, depending on income and care percentage. So if you earn more and provide less care, you’ll likely pay more child support.

Importantly, the formula doesn’t raise payments simply because of age, but age does feed into the cost component, which then influences the final amount.

This makes it fairer for both parents as children’s needs evolve.

Key Takeaway: The child support formula indirectly raises payments with age by adjusting the cost of care as children get older.

What Happens When Your Child Turns 13?

When your child turns 13, Services Australia updates the cost assumption used in the formula. This often leads to a reassessment of your child support amount.

The change won’t be automatic unless your case is already being regularly reviewed or you report a change in circumstances.

You can ask for a reassessment if:

• Your child recently turned 13
• Your income or care percentage has changed
• You believe the current assessment no longer reflects the true cost of care

This adjustment reflects the increased costs typically associated with raising teenagers, including higher educational needs, transport, and lifestyle expenses.

Key Takeaway: A child turning 13 can trigger a reassessment due to increased cost assumptions, especially if your case is reviewed or you report changes.

Child Support After Age 18

In most cases, child support ends when your child turns 18. However, there are exceptions:

• If your child is still in full-time secondary education, you may apply to extend payments until the end of that school year.
• You must apply before the child turns 18 to ensure continuity.

This extension is not automatic—you’ll need to complete a request and provide evidence of the child’s ongoing education.

If approved, payments continue only for the defined period and don’t stretch beyond the school year.

Key Takeaway: Child support typically ends at 18, but can be extended if your child is still in high school—apply early to avoid disruption.

Other Factors That Affect Payment Changes

While age is one influencing factor, there are several other reasons your payments might change:

• Income changes (yours or the other parent’s)
• Changes in care arrangements
• New children in either parent’s household
• Changes in government policy or thresholds

If you’re not sure why your payment changed or think it should change, you can request a review or seek legal advice. It’s important to keep your details up to date with Services Australia so they can assess your case accurately.

So, does child support increase with age? Yes, it can—particularly when your child turns 13 and enters a higher cost bracket.

But the actual amount depends on your income, how much care you provide, and whether your case is reviewed or reassessed.

Being proactive in reporting changes and understanding the formula helps ensure your payments reflect your child’s real-life needs.