How to Establish Paternity in California
A Complete Legal Guide

What Is Paternity and Why Does It Matter?

Paternity is the legal recognition of a man as a child’s father. It is distinct from biological fatherhood. A man can be the biological father of a child and still have zero legal rights if paternity has not been formally established. Conversely, a man who is not biologically related to a child can be the child’s legal father if the law treats him as such through marriage, a signed declaration, or a court order.

For married couples, paternity is usually automatic—California law presumes that a child born during marriage is the husband’s child. FC §7540 But for unmarried parents, there is no such presumption. The biological father is legally a stranger to the child until paternity is established through one of the methods described below.

The consequences of not establishing paternity are significant for everyone involved:

• For the father — Without legal paternity, an unmarried father has no right to custody, visitation, or any say in the child’s upbringing—even if he has been actively parenting the child. If the father is not on the birth certificate, he is a legal stranger to the child until paternity is formally established.
• For the mother — Without legal paternity, the mother cannot obtain a court order for child support. She bears the full financial burden alone.
• For the child — Without legal paternity, the child cannot access the father’s health insurance, inherit from the father under intestate succession Probate Code §6452, receive Social Security survivor benefits, or claim military dependent benefits.

Establishing paternity is not about blame or conflict. It is about giving your child every legal benefit and protection they deserve, and ensuring that both parents share the rights and responsibilities of raising that child.

Four Ways to Establish Paternity in California

California law provides four distinct methods for establishing legal fatherhood. The right method depends on whether the parents are married, whether both parents agree on paternity, and whether genetic testing is needed.

1. Voluntary Declaration of Paternity

The most common method for unmarried parents. Both the mother and father sign a government form—typically at the hospital shortly after the child’s birth, but it can also be completed later at a county registrar’s office or through the Department of Child Support Services (DCSS). Once signed and filed, the declaration has the same legal force as a court judgment of paternity. FC §7573

2. Presumption of Paternity Through Marriage

If a child is born during a marriage, the husband is conclusively presumed to be the child’s father. FC §7540 This is not a guess—it is a legal fact unless rebutted through the narrow procedures of FC §7541. Additional presumptions exist for men who meet the criteria of FC §7611, such as receiving the child into their home and openly holding the child out as their own.

3. Court Order Through a Paternity Action

When parents disagree about paternity, or when no voluntary declaration has been signed, either parent (or DCSS on behalf of the state) can file a petition to establish the parent-child relationship under FC §7630. The court resolves the question—often with the aid of genetic testing—and enters a judgment of paternity.

4. Genetic (DNA) Testing

DNA testing is not a standalone method for establishing paternity—it is the evidentiary tool the court uses within a paternity action. Under FC §7646, the court may order genetic testing at the request of any party. Modern DNA testing is extraordinarily accurate, with probability-of-paternity results typically exceeding 99.9%.

The Voluntary Declaration of Paternity — FC §7570–7577

The Voluntary Declaration of Paternity (VDP) is a state-provided form that allows unmarried parents to establish legal paternity without going to court. It is the primary tool California uses to encourage the early establishment of paternity for children born to unmarried parents.

How It Works

Hospitals in California are required to provide VDP forms and information to every unmarried mother and her partner at the time of the child’s birth. FC §7571 Both the mother and the father sign the form in the presence of a witness or a notary. Once the signed declaration is filed with DCSS, it has the same force and effect as a judgment of paternity entered by a court. FC §7573

You do not have to sign the VDP at the hospital. Many parents choose to sign later—at the local county recorder’s office, a DCSS office, or through a qualified agency. There is no deadline to sign a VDP, but the sooner it is completed, the sooner the father’s rights and the child’s benefits are secured.

Rescinding a Voluntary Declaration

If a parent changes their mind, the law provides a limited window to rescind the declaration:

• Within 60 days of signing — Either parent may rescind the VDP by filing a written rescission with DCSS. No reason is required. FC §7575(a)
• After 60 days — The declaration can only be set aside by filing a motion in court and proving fraud, duress, or material mistake of fact. This motion must be filed within two years of the date the declaration was signed. FC §7575(b)

The VDP also triggers the father’s right to be named on the child’s birth certificate. If the father was not listed at birth, signing a VDP allows both parents to request an amended birth certificate that includes the father’s name.

Establishing Paternity Through Court

When the parents cannot agree on paternity—or when the alleged father denies being the biological parent—the question must be resolved through a court proceeding. This is formally known as an action to determine the existence of a parent-child relationship under FC §7630.

Who Can File

A paternity action can be filed by any of the following:

• The child’s mother
• A man alleging he is the father
• The child (through a guardian ad litem)
• The Department of Child Support Services (DCSS) — DCSS frequently files paternity actions in connection with public assistance cases or child support enforcement

The Court Process

A typical court-based paternity case follows these steps:

1. Filing the petition — The petitioner files a complaint to establish the parent-child relationship in the family court of the county where the child or the alleged father resides.
2. Service of process — The respondent must be formally served with the petition and summons.
3. Genetic testing — Either party (or the court on its own motion) may request court-ordered DNA testing under FC §7646. Testing involves a simple cheek swab from the mother, the child, and the alleged father.
4. Results and judgment — If DNA testing confirms paternity (probability of paternity 99% or higher), the court enters a judgment of paternity. The judgment legally establishes the man as the child’s father for all purposes.
5. Orders — Along with the paternity judgment, the court can immediately enter orders for custody, visitation, and child support.

What If the Alleged Father Refuses DNA Testing?

If the alleged father refuses to submit to court-ordered genetic testing, the court may draw an adverse inference—meaning it can presume that the test results would have established paternity. FC §7551 In practice, refusing a DNA test almost guarantees that the court will enter a paternity judgment against the refusing party.

Rights and Responsibilities That Come With Paternity

Once paternity is legally established—whether through a VDP, a court judgment, or the marital presumption—the father and child gain a comprehensive set of legal rights. At the same time, both parents take on enforceable responsibilities.

Rights of the Father

• Equal custody rights — The father has the same right as the mother to seek legal and physical custody of the child. FC §3010
• Visitation — If the father is not granted primary custody, he has the right to reasonable visitation (parenting time) with the child.
• Decision-making authority — A father with joint legal custody shares in major decisions about the child’s education, healthcare, and religious upbringing.
• Right to be named on the birth certificate — The father can request to be added to or listed on the child’s birth certificate.
• Consent to adoption — No adoption of the child can proceed without the legal father’s consent or a court order terminating his parental rights.

Rights of the Child

• Financial support from both parents — The child is entitled to child support calculated under California’s guideline formula. FC §4055
• Health insurance — The father may be required to provide health insurance coverage for the child.
• Inheritance rights — The child can inherit from the father under California’s intestate succession laws. Probate Code §6452
• Social Security benefits — The child may be eligible for Social Security survivor or disability benefits based on the father’s earnings record.
• Military benefits — If the father is a service member, the child may qualify for TRICARE, commissary access, and other military dependent benefits.
• Knowledge of identity and medical history — The child gains the right to know their full parentage, including the father’s genetic medical history.

Obligations of the Father

• Child support — Both parents are obligated to support their child financially. FC §4001 Child support is calculated using California’s guideline formula under FC §4055.
• Health insurance — The court may order the father to add the child to his employer-provided health plan.
• Childcare and educational expenses — The court can allocate additional costs beyond basic guideline support.

When Paternity Is Disputed

Not every paternity case is straightforward. Disputes arise when a man denies being the father, when a mother names someone the father and he disagrees, or when a previously established paternity is called into question by new evidence. California law provides specific procedures—and strict deadlines—for each scenario.

Contesting a Voluntary Declaration

As discussed above, a VDP can be rescinded within 60 days for any reason. FC §7575(a) After 60 days, the only path is a court motion proving fraud, duress, or material mistake of fact—and that motion must be brought within two years of the date the declaration was signed. FC §7575(b) After two years, setting aside a VDP is virtually impossible absent extraordinary circumstances. For a deeper discussion of these challenges, see our guide on paternity fraud in California.

Challenging the Marital Presumption

The marital presumption under FC §7540 is conclusive: a child born to a married woman living with her husband is legally the husband’s child. The only way to rebut this presumption is by filing a motion for genetic (blood) testing within two years of the child’s birth under FC §7541. Only the husband or the mother may bring this motion—the alleged biological father generally cannot.

Disputed DNA Results

DNA testing is highly reliable, but disputes can arise over testing procedures, chain of custody, or laboratory errors. Either party may request a second round of testing. The court evaluates genetic test results under the standards of FC §7550–7557 and may appoint an independent laboratory if there is a genuine dispute over the reliability of initial results.

Refusal to Submit to Testing

A party who refuses a court order to submit to genetic testing faces serious consequences. Under FC §7551, the court can draw an adverse inference from the refusal. In most cases, this means the court will presume the test would have confirmed paternity and enter judgment accordingly. Refusal is not a viable defense strategy.

Paternity and Child Support

Establishing paternity and establishing child support are deeply intertwined. In most cases, the paternity judgment and the initial child support order are entered in the same court proceeding. Once paternity is established, both parents have a legal duty to support their child financially. FC §4001

How Support Is Calculated

California uses a statewide guideline formula under FC §4055 to calculate child support. The formula accounts for each parent’s net disposable income, the percentage of time each parent has physical custody, tax filing status, and mandatory deductions. The guideline amount is presumed correct, and courts deviate from it only in limited circumstances. For more details, visit our California child support guide.

Retroactive Child Support

One of the most significant financial consequences of a paternity judgment is retroactive child support. When paternity is established, the court can order the father to pay support dating back up to three years before the date the paternity action was filed. FC §4009 This can result in a substantial lump-sum obligation on top of ongoing monthly payments.

DCSS Involvement

The California Department of Child Support Services plays a major role in paternity and support cases. DCSS can:

• File a paternity action on behalf of a custodial parent or the state
• Arrange free genetic testing for the parties
• Obtain a default judgment of paternity if the alleged father fails to respond
• Calculate and enforce child support orders, including wage garnishment, tax intercepts, and license suspension

Even parents who are not receiving public assistance can open a child support case through DCSS. The agency charges a nominal annual fee (currently $35) and can handle the entire process of establishing paternity and support without the need for a private attorney. However, DCSS represents the interest of the child, not either parent individually. If you need advocacy for your custody or visitation rights, or if the case is contested, working with a private attorney is advisable.

Working With a Paternity Attorney

While some paternity matters are straightforward—particularly when both parents agree and simply need to complete a Voluntary Declaration—many cases involve complexities that require skilled legal representation. An experienced paternity lawyer can make the difference between a fair outcome and one that leaves you at a permanent disadvantage.

When You Need an Attorney

Legal representation is especially important when:

• The alleged father denies paternity and you need to pursue a court action
• You are an unmarried father seeking custody or visitation rights
• You signed a VDP and now want to challenge it based on fraud or mistake
• You need to challenge the marital presumption within the two-year window
• DCSS has filed a paternity action against you and you want to contest it or negotiate terms
• You are concerned about retroactive child support exposure
• There are overlapping issues involving custody, domestic violence, or divorce

What to Expect in a Paternity Case

A typical paternity case handled by an attorney involves:

1. Initial consultation — Your attorney reviews the facts, identifies which paternity pathway applies, and explains your rights and potential exposure.
2. Filing or responding — Your attorney files the petition (or responds to one filed against you) and ensures proper service of process.
3. Genetic testing — If paternity is disputed, your attorney requests court-ordered DNA testing and ensures the results are properly admitted.
4. Negotiation — Many paternity cases settle before trial. Your attorney negotiates custody, visitation, and support terms that protect your interests.
5. Judgment — The court enters a paternity judgment along with orders for custody, visitation, and child support.

How Family Law Matters Handles Paternity Cases

At Family Law Matters, we represent both mothers and fathers in paternity cases throughout Riverside County—including Temecula, Murrieta, Wildomar, Canyon Lake, Menifee, Sun City, and Corona. Whether you need to establish paternity, challenge a declaration, or fight for custody rights once paternity is confirmed, our team provides focused, statute-informed advocacy designed to protect your rights and your child’s welfare.

We understand that paternity cases are personal. Many of our clients are fathers who want to be present in their child’s life and need the law to recognize that relationship. Others are mothers who need to secure financial support for a child they are raising alone. Whatever your situation, we approach every case with the goal of reaching a fair and enforceable resolution as efficiently as possible.