How to Set Aside a Paternity Judgment or Child Support Order in California

What this guide covers

In California, a person can be legally declared the parent of a child and ordered to pay child support even if they are not the biological parent. This can happen through a default judgment (where the person never responded to the court papers), a voluntary declaration of paternity signed at the hospital, or a court finding based on the presumption of parentage.

If you have been established as a parent and believe you are not the biological father, California law provides specific procedures to challenge that finding and ask the court to cancel (set aside) the judgment. This guide explains when you can challenge paternity, what forms you need, the deadlines that apply, and what happens to child support once paternity is set aside.

How someone becomes a legal parent without being the biological father

California law recognizes several ways a person can be established as a legal parent:

• Default judgment — A child support case was filed (often by the Department of Child Support Services) and you never responded. The court entered a judgment against you by default, including a finding of parentage.
• Voluntary Declaration of Paternity — You signed a declaration at the hospital or through a county office acknowledging you are the father. Once the 60-day rescission period passes, this has the same force as a court judgment (Family Code § 7573).
• Presumption of parentage — You were married to the mother when the child was born, or you lived with the child and held the child out as your own (Family Code § 7611).
• Court judgment — A court found you to be the parent after a hearing.

Each of these has a different procedure for challenging paternity. The most common scenario is a default judgment where the person was never properly served.

Setting aside a default judgment (you were never served)

If you were never served with the court papers — meaning you never received the Summons and Complaint — the judgment may be void. Under Code of Civil Procedure § 473.5, you can file a motion to set aside the default and the default judgment.

Deadlines

• If you received a Notice of Entry of Default by mail, you must file within 180 days from the date the notice was mailed.
• If you never received any notice, you must file within 2 years from the date the default judgment was entered.

What to file

File a Notice of Motion to Set Aside Default along with a declaration explaining that you were never served. You must also attach a proposed response to the original complaint. For government child support cases, attach a completed FL-610 (Answer to Complaint Regarding Parental Obligations).

Setting aside paternity based on genetic testing

Under Family Code § 7646, a previously established father, the mother, or the child can file a motion to cancel (set aside) a judgment of parentage if genetic testing shows that the established father is not the biological father.

Who can file

• The previously established father
• The mother
• The child
• A legal representative of any of these persons

What to file

Use these Judicial Council forms:

• FL-272 — Notice of Motion to Cancel (Set Aside) Judgment of Parentage
• FL-273 — Declaration in Support of Motion to Cancel (Set Aside) Judgment of Parentage
• FL-274 — Information Sheet (instructions for completing the motion)

Do you need a DNA test before filing?

No. You do not need to present DNA results to file the motion. However, the court will need genetic testing results before it can grant the motion. You can ask the court to order genetic testing using form FL-627 (Order for Genetic Testing). If the Department of Child Support Services (DCSS) is involved in your case, they will pay for the testing.

Setting aside a Voluntary Declaration of Paternity

If you signed a Voluntary Declaration of Paternity at the hospital or through a county office, there are two paths depending on timing:

Within 60 days of signing

You can rescind (cancel) the declaration by filing a rescission form with the Department of Child Support Services. No court hearing is needed (Family Code § 7575(a)).

After 60 days

You must file with the court. The grounds are limited to fraud, duress, or material mistake of fact (Family Code § 7575(b)). Use these forms:

• FL-280 — Request for Hearing and Application to Cancel (Set Aside) Voluntary Declaration of Parentage
• FL-281 — Information Sheet (instructions for completing the application)

What the court considers

When deciding whether to set aside a paternity judgment, the court weighs several factors under Family Code § 7648.4:

• The best interest of the child
• Whether the established father provided financial support believing he was the biological father
• Whether the established father developed a relationship with the child
• The age of the child
• The length of time since the judgment was entered
• Whether setting aside the judgment would leave the child without a legal parent

Even with a DNA test showing non-paternity, the court has discretion. If the established father has been the child's functional parent for many years, the court may weigh the child's interest in maintaining that relationship.

What happens to child support if paternity is set aside?

If the court grants your motion and sets aside the judgment of parentage:

• Future support: Your obligation to pay child support going forward is terminated.
• Past-due support (arrears): Under Family Code § 7648.4, the court may forgive arrears that accrued before the motion was filed, but it is not required to. The court considers whether payments were made under a reasonable belief of paternity and the financial circumstances of both parties.
• Wage garnishment and enforcement: If DCSS is garnishing your wages, the set-aside order stops future collections. Contact DCSS to ensure the order is processed.

What forms do you need?

To set aside a judgment of parentage (FC § 7646)

To set aside a Voluntary Declaration of Paternity

To respond to a government child support case

Step-by-step process

Step 1: Determine which type of judgment you have

Get a copy of the judgment from the court. Determine whether paternity was established by default judgment, voluntary declaration, or a court finding after a hearing. This determines which forms and legal grounds apply.

Step 2: Check your deadlines

Deadlines vary depending on how paternity was established:

• Default (never served): 180 days from notice or 2 years from entry (CCP § 473.5)
• Voluntary declaration (within 60 days): File rescission with DCSS
• Voluntary declaration (after 60 days): File FL-280 showing fraud, duress, or material mistake of fact
• Judgment of parentage (FC § 7646): No specific statutory time limit, but courts consider the length of delay as a factor

Step 3: Fill out and file your forms

Complete the appropriate forms (FL-272/FL-273 for a judgment, FL-280 for a voluntary declaration). Read the information sheet (FL-274 or FL-281) carefully before filling out the forms. File them with the court that entered the original judgment.

Step 4: Serve the other parties

You must serve a copy of your filed motion on the other parent and on the local Department of Child Support Services if they are involved in your case. Service must be completed at least 16 court days before the hearing date (plus additional time for mailing if served by mail).

Step 5: Request genetic testing

If you do not already have DNA results, ask the court to order genetic testing using form FL-627. The court will set a testing date. Both the alleged father and the child must be tested. In DCSS cases, the agency pays for testing.

Step 6: Attend the hearing

At the hearing, the judge reviews the genetic testing results and any other evidence. If the DNA test shows you are not the biological father, and the court finds that setting aside the judgment is appropriate, the judge will grant the motion and enter an order on form FL-278 (Order After Hearing on Motion to Cancel Judgment of Parentage).

How much does this cost?

Where to get help

Forms checklist

•  FL-272 — Notice of Motion to Cancel Judgment of Parentage
•  FL-273 — Declaration in Support of Motion
•  FL-627 — Order for Genetic (Parentage) Testing
•  FL-610 — Answer to Complaint (if default in DCSS case)
•  FW-001 — Request to Waive Court Fees (if applicable)