Binding and limited child support agreements
Parents don't have to accept the formula result. You can agree on a different amount and register that agreement with Services Australia so it's enforceable. There are two types, and the difference between them is mostly about how hard it is to get out of later.
Limited agreements
A limited agreement can be made without either parent getting legal advice. In exchange, the law imposes protections: there must already be an administrative assessment in place, and the agreed annual rate must be at least the assessed rate. You cannot use a limited agreement to pay less than the formula says.
Either parent can end a limited agreement after three years, or earlier if the assessed rate changes by more than 15% in circumstances that weren't intended when the agreement was made. That escape hatch is the whole point of the "limited" label.
Binding agreements
A binding agreement is far more durable. Both parents must get independent legal advice before signing, and each solicitor must certify that advice was given. There's no requirement that the amount match or exceed the formula — a binding agreement can be for more, for less, or for a lump sum.
Once signed, it can only be ended by a new binding agreement that both parents sign, a termination agreement, or a court order setting it aside. Courts set them aside rarely, generally requiring fraud, undue influence, unconscionable conduct, or exceptional circumstances causing hardship to a child. Changing your mind, or a change in income, is not enough.
Comparison
| Limited | Binding | |
|---|---|---|
| Legal advice required | No | Yes, both parties |
| Assessment required first | Yes | No |
| Can pay below formula rate | No | Yes |
| Ends after 3 years | Either parent can end it | No |
| 15% change escape | Yes | No |
| Lump sums allowed | Limited | Yes |
Non-periodic payments
Both agreement types can cover things other than cash transfers — school fees, private health insurance, mortgage payments on the home the children live in. These can be credited against the child support liability, or paid in addition to it, and the agreement should say clearly which. Ambiguity on that point is the single most common source of later disputes.
Which one fits
Limited agreements suit parents who want to formalise a working arrangement slightly above the formula amount without legal costs. Binding agreements suit situations involving lump sums, property settlements, school fee commitments, or where certainty over many years matters more than flexibility. Given a binding agreement can lock in an amount for a decade or more regardless of income changes, the independent advice requirement isn't a formality — it's the point.
Estimate your child support →This is general information about how the child support system works, not legal or financial advice. For advice about your own circumstances, speak to Services Australia or a family lawyer.