Colorado Paternity Laws: Establishing, Contesting, and Rights

Colorado’s paternity laws, set out in the Uniform Parentage Act at C.R.S. § 19-4-101 through 19-4-130, give unmarried parents three ways to establish legal fatherhood: an automatic legal presumption, a signed Acknowledgment of Parentage, or a court order. Until one of those routes is completed, a biological father has no guaranteed right to parenting time, no say in major decisions, and no automatic place on the birth certificate, and the child has no legal claim to support, inheritance, or benefits through him.

Who Colorado Already Treats as a Legal Parent

Some people are presumed parents without filing anything. Under C.R.S. § 19-4-105, a presumption of parentage applies if any of the following is true:

You were married to or in a civil union with the birth parent when the child was born, or the child was born within 300 days after that marriage or civil union ended by death, divorce, or legal separation.
You and the birth parent attempted to marry or form a civil union before the birth in a ceremony that appeared lawful, even if the union was later declared invalid.
After the birth, you married the birth parent and either acknowledged parentage in writing, were named on the birth certificate with your consent, or are legally obligated to support the child.
While the child was a minor, you took the child into your home and openly held the child out as your own.
Genetic testing shows a 97% or higher probability that you are the biological parent.

These presumptions are strong. Overturning one takes clear and convincing evidence, which is a higher standard than the “more likely than not” rule used in most civil cases. The statute uses gender-neutral language and applies the same presumptions to civil union partners and same-sex couples.¹²

Signing an Acknowledgment of Parentage

When both parents agree, the simplest route is a voluntary Acknowledgment of Parentage (AOP). The form is available at the hospital around the time of birth or through Colorado Vital Records, and no court appearance is required.³

Both parents provide full legal name, Social Security number, date of birth, and address, along with the child’s name, birth date, and birth facility. Each parent signs in front of a witness. If the birth parent is currently married to or in a civil union with someone other than the person signing as the second parent, that spouse or civil union partner has to sign a separate denial of parentage before the AOP is valid.¹

A signed AOP becomes a legal finding of parentage 60 days after signing, or on the date of any earlier court or administrative proceeding involving the child, whichever comes first. Either parent can rescind their signature during that 60-day window for any reason. After it closes, the acknowledgment carries the force of a court order and can only be undone by proving fraud, duress, or a mistake about a material fact, and any existing child support keeps running unless a judge finds good cause to suspend it.¹

Filing a Court Case to Establish Parentage

When one parent refuses to sign, or the parents disagree about who the father is, the case goes to court. A mother, a father, the child, a child’s representative, or the state child support enforcement agency can file to establish or disclaim parentage.⁴

You start with Form JDF 1501, the Petition to Determine Parentage, filed in the district court of the county where the child or the alleged parent lives. The filing fee is $268. You’ll also complete the top of a Summons (JDF 1502) and a proposed Final Parentage Order (JDF 1516); the court fills in the rest.⁵⁶

The other parent then has to be personally served, which means someone other than you physically delivers the papers. If you genuinely can’t locate the other parent, you can ask the court for permission to use alternative service, typically publication in a newspaper, by filing a Motion for Alternative Service (JDF 1301). The court expects proof that you tried every reasonable way to find and serve the other parent first.⁷

After hearing both sides, the judge enters a Judgment of Parentage. A single order can decide parentage along with child support, parenting time, decision-making, medical insurance, and even the costs of pregnancy and birth.⁸

Genetic Testing

DNA testing is usually the deciding factor in a contested case. Under C.R.S. § 13-25-126, any party or the judge can request it, and the court then orders the alleged mother, alleged father, and child to submit.⁹

If both parents agree, they sign Form JDF 1506 (Agreement for Genetic Testing) before a notary or court clerk and share the cost. If one parent refuses, the other files a Motion for Genetic Testing (JDF 1505), and the moving party pays the initial fee.⁵ Legal-grade DNA tests generally run $300 to $600.

Refusing a court-ordered test carries real risk. The judge can resolve the whole parentage question against the person who won’t cooperate, effectively treating the refusal as an admission. And a test result showing 97% or higher probability makes the tested person a presumed parent, shifting the burden to them to disprove the relationship.⁹¹

Deadlines That Can Bar a Claim

Colorado sets different time limits depending on who is filing and what they want.

A mother, father, or the child support enforcement agency can file to establish paternity any time before the child turns 18. A child whose paternity was never established has until age 21 to file on their own.⁴

Disclaiming parentage that arose from a presumption is much tighter. A presumed father has to file within a reasonable time after learning facts suggesting he isn’t the biological parent, and no later than five years after the child’s birth. After five years, the legal relationship is permanent regardless of biology.¹⁰ A man who has doubts and waits too long can lose the right to challenge paternity forever.

These deadlines don’t stretch inheritance or succession rights beyond what Colorado’s probate law otherwise allows.⁴

Undoing an Existing Paternity Finding

How you challenge established paternity depends on how it was set up in the first place.

If You Signed an Acknowledgment

Within 60 days of signing an AOP, you can simply rescind it. No reason required. After that, the acknowledgment is treated as a legal finding, and undoing it means going to court and proving fraud, duress, or a mistake about a material fact. The burden is on the person challenging it, and any existing child support keeps running while the case is pending unless a judge orders otherwise.¹

If Paternity Rests on a Presumption

If paternity comes from a presumption rather than a signed AOP, you file an action to disclaim. The five-year cap from birth is hard, and the court also looks at how quickly you moved once you had reason to doubt. Filing a few months after learning the facts reads very differently than waiting three years.¹⁰

Once a presumption is rebutted, the same case can establish paternity for a different man, as long as he’s been made a party. That avoids running two separate cases when the real question is which of two people is the father.

What Established Paternity Gives the Child and the Parent

A legal determination turns a biological connection into an enforceable one, and it works in both directions.

Parenting Time and Decision-Making

The legal father gains standing to ask for parenting time and for allocation of parental responsibilities, which is Colorado’s term for authority over major decisions about education, healthcare, and religious upbringing. Without a paternity order, a biological father has no legal right to be part of any of those decisions, no matter how involved he has been day to day. The court can address parenting time and decision-making in the same order that establishes paternity.⁸

Child Support and Financial Obligations

Both parents become financially responsible based on their incomes and the child’s needs. A support order typically covers regular payments, contributions to health insurance premiums, uninsured medical costs, and childcare. The judge can also order the father to reimburse a share of pregnancy and delivery expenses and to pay for genetic testing. Support usually comes as periodic payments, but a court can order a lump sum or an annuity if that better serves the child.⁸

When a parent falls behind, Colorado Child Support Services can withhold income from paychecks, intercept tax refunds, suspend licenses, report delinquencies to credit bureaus, and take the case back to court.¹¹ A parent owed support can also file for wage garnishment directly through the court.¹²

Inheritance and Benefits

Paternity gives the child inheritance rights if the father dies without a will. The child also becomes eligible for Social Security survivor benefits, veterans’ benefits if the father served in the military, and coverage under employer-provided health insurance. That protection can matter a great deal if something happens to the father while the child is still a minor.

1
Justia. Colorado Code 19-4-105 – Presumption of Paternity
2
Colorado Revised Statutes. Colorado Code 19-4-105 – Presumption of Paternity
3
Colorado Child Support Services. Parentage
4
Justia. Colorado Code 19-4-108 – Statute of Limitations
5
Colorado Judicial Branch. Determine Parentage
6
Colorado Judicial Branch. List of Fees
7
Colorado Judicial Branch. How to Serve Court Papers in Divorce and Custody Cases
8
Justia. Colorado Code 19-4-116 – Judgment or Order
9
Justia. Colorado Code 13-25-126 – Genetic Tests
10
Justia. Colorado Code 19-4-107 – Determination of Father and Child Relationship
11
Colorado Child Support Services. Enforcing Orders
12
Colorado Judicial Branch. Garnishment to Pay Child Support or Maintenance