This website is for use by legal professionals (lawyers and law practices) only. If the information is used incorrectly, you could risk losing money or your legal rights. If you are a member of the public looking for free advice about your legal problems please visit, or contact our Legal Help advice line on 1300 792 387, Monday to Friday from 8 am to 6 pm. 

If you decide to use or rely on the information or make decisions based on the information in this website (which VLA does not recommend) VLA is not liable to you or any third party in any way for any loss, damage, costs or expenses you or they may suffer or incur as a result.

Proof of parentage

Information about how parentage is determined under the child support scheme.

Sometimes it will be necessary to provide proof that a person is a parent of the child and therefore must be held financially responsible, for example, to receive child support.

Also if a parent is already paying child support, but they dispute parentage of the child they may need proof to support their claim.

Even if a parent pays no child support, they may want to know whether a child is their biological child.

If either parent wants proof of parentage they can request a parentage test.

Parentage testing

A DNA test can be carried out to determine whether someone is the biological parent.

This test involves taking samples from the biological parents and the child. The samples are usually mouth swabs, but DNA could also be collected in another way. The test results will not say that a man is definitely the father, but will state that the man is highly likely to be the father—or not.

Sometimes a parent may want this test done, just for peace of mind. They may have been married for years and have accepted the child as their own, but are now seeking proof. VLA does not generally fund these matters unless there is another substantive issue.

People can choose to pay for their own DNA tests. The tests should be done by an accredited laboratory.

For a list of accredited laboratories see National Association of Testing Authorities (NATA)—DNA analysis(opens in a new window).


Tests cost approximately $700 to $800. People who are eligible for help from the Child Support Legal Service may get help with the cost of the tests or may not have to pay at all, depending on their financial situation.

Men who deny paternity may have to pay for the test to be done, but this could be refunded if the report shows that they are not the father.

Test may be ordered by the court

A person who is named as the father in a child support assessment application may volunteer to have the test or a court may order them to be tested.

Despite the court order, the court will not force someone to have a test. However, if a person refuses to be tested the court could make a decision, based on the refusal, declaring that person to be the father.

If the test is positive

If the person tested is found to be the biological parent and accepts that they have responsibility to pay child support they do not need to go to court.

If the parent refuses to accept responsibility, the carer will have to apply to court and the test will be used as evidence of parentage.

Once a court order has been made declaring parentage, it must be lodged with the Registrar of Child Support at Services Australia who will then make the child support assessment.

Payment backdated to application date

If the court declares that the person is a parent, child support must be paid from the date that the application was initially made to the Registrar of Child Support at Services Australia.

If the test is negative

If the person tested is found not to be the father, they have no obligation to pay child support. The person can apply to court for an order declaring that they are not the parent and so not liable for child support. They should register this declaration with the Child Support Agency.

If they have been paying child support they can go to court for an order seeking repayment of money that has already been paid. There are a number of factors that the court will consider when using its discretion whether the money should be repaid. These include:

  • whether the payer could reasonably have known that they were not a biological parent
  • whether they were misled by the other parent about their parental status
  • the financial circumstances of both parties
  • the relationship between the payer parent and the child.

See Child support payments and debts(opens in a new window) and ss. 107, 143—Child Support (Assessment) Act 1989 (Cth)(opens in a new window).

More information


Child Support (Assessment) Act 1989 (Cth)

  • s. 5—defines parent
  • s. 106A—declaration that a person should be assessed in respect of the costs of the child
  • s. 107—declaration that a person should not be assessed for paying for cost of a child as they are not a parent of the child
  • s. 143—amounts paid in child support where no liability exists (repayment provision)

See Child Support (Assessment) Act 1989 (Cth)(opens in a new window).

Family Law Act 1975 (Cth)

  • s. 69U—what happens if presumptions conflict
  • s. 69V—evidence of parentage
  • s. 69VA—court power to order a declaration as to parentage
  • s. 69W—orders for carrying out parentage testing procedures
  • s. 69X—other orders that a court can make about parentage testing (for example ordering a person to submit to a medical procedure)
  • s. 69XA—costs in relation to parentage testing pursuant to an international agreement or assessment
  • s. 69Y—no penalty for refusal if person is over 18, however adverse inference may be drawn
  • s. 69Z—deals with situations where the person to be tested is under 18 years old
  • s. 69ZD—situations where court may order parentage testing in relation to international maintenance agreements

See Family Law Act 1975 (Cth)(opens in a new window).


The Child Support Guide

See Child Support Guide—2.1.3: Parentage(opens in a new window).

Services Australia

The department's website has information designed to help parents to navigate the child support system.

See Services Australia—The Parent's guide to child support(opens in a new window).

National Association of Testing Authorities (NATA)

NATA is the national accreditation body for the accreditation of laboratories,including those who test DNA samples. The site has a database of all accredited laboratories,

See National Association of Testing Authorities (NATA)—Find accredited facilities(opens in a new window).