Paternity
Parentage is the legal link between a parent and a child, and it's what everything else depends on: custody, child support, inheritance, the right to make decisions. For unmarried parents, it isn't automatic. We help parents across the Pacific Northwest establish, confirm, or challenge parentage, and then sort out the support and parenting that follow.
Talk to an attorneyFounded
1965
Attorneys
11
AV-rated
Martindale-Hubbell
Office
Bellevue, WA
Founded
1965
Attorneys
2
AV-rated
Martindale-Hubbell
Office
Bellevue, WA
Paternity and parentage attorneys for Bellevue and Seattle families
Washington's Uniform Parentage Act, RCW 26.26A, governs who is legally a child's parent, and it covers far more than a father and a paternity test. It recognizes parentage through marriage, through a signed acknowledgment, through a court adjudication, and through newer routes like de facto parentage and assisted reproduction. Establishing parentage matters because it unlocks both sides of the relationship: a parent's right to time with the child and a say in decisions, and the child's right to support, inheritance, and benefits. We handle the full range, for married and unmarried parents, same-sex couples, and families built through assisted reproduction.
Parentage cases follow a few clear paths, and which one fits depends on the family. We establish parentage through acknowledgment, presumption, or a court order; we explain why establishing it matters for support and custody; we handle genetic testing and disputed or challenged parentage; we establish parentage for de facto parents, same-sex couples, and assisted-reproduction families; and we move from parentage to a support order and a parenting plan once the legal link is settled.
Establishing parentage: the three main paths
Washington recognizes parentage in a few ways under RCW 26.26A. The simplest is a voluntary Acknowledgment of Parentage, a signed form (often completed at the hospital) that, under RCW 26.26A.200 and following, becomes the equivalent of a court order. Parentage can also be presumed, most commonly when the parents are married or a person has openly treated the child as their own, under RCW 26.26A.115. When parentage is in dispute, a court adjudicates it, often with genetic testing. We figure out which path fits and handle the paperwork or the petition.
Why establishing parentage matters
Until parentage is established, an unmarried parent has no automatic legal rights or duties. Establishing it is what gives a parent standing to seek a parenting plan and time with the child, and it's what entitles the child to support, inheritance, health coverage, Social Security, and a full medical history. It runs both directions: rights and responsibilities together. Getting it on record early, rather than during a later crisis, saves a great deal of difficulty.
Genetic testing and challenged parentage
When parentage is contested, genetic testing under RCW 26.26A.300 and following usually resolves the biological question. The legal question can be more involved. A signed acknowledgment can be rescinded within 60 days, but after that it can only be challenged on narrow grounds like fraud, duress, or a material mistake of fact, and within strict time limits. We handle both establishing parentage over a denial and, in the right cases, disestablishing a parentage that genetic testing and the law no longer support.
Modern families: de facto parents, same-sex couples, and assisted reproduction
Parentage law has caught up with how families are actually built. Washington recognizes a de facto parent, someone who has fully functioned as a parent with the support of a legal parent, under RCW 26.26A.440, codifying the rule the state Supreme Court announced in In re Parentage of L.B., 155 Wn.2d 679 (2005). The Act also establishes parentage for children born through assisted reproduction under RCW 26.26A.600 and following, and it gives Washington a clear surrogacy framework through gestational agreements under RCW 26.26A.700 and following. We help same-sex couples and parents using assisted reproduction make sure both legal parents are recognized, and we advise when a confirmatory adoption adds protection across state lines.
After parentage: support and a parenting plan
Establishing parentage is the front door, not the whole house. Once the legal link is set, child support follows Washington's statutory schedule under RCW 26.19, and time with the child is set by a parenting plan under RCW 26.09, the same framework that governs a divorce with children. We carry the matter through from establishing parentage to a support order and a workable parenting plan. For ongoing custody and support, see Child Support & Custody.
Sixty years representing Pacific Northwest families, often the same families whose businesses, trusts, and estates the firm already handles. When a family-law matter touches a company or a trust, you're not starting over with a stranger.
Continuity, not a hand-off.
Many family-law clients are already firm clients. The attorney handling your case may be the one who set up the business or the trust now in question, which means less time spent explaining and fewer surprises.
Settlement-minded, trial-ready.
We resolve most family-law matters without a trial, because it's better for the family and the budget. But when a case has to be tried, the firm's litigators are ready, and the other side knows it.
Straight about what's ahead.
These matters are hard enough without a lawyer overselling. We give you a clear map of the next several months, tell you what a case is realistically worth fighting over, and what isn't.
The attorneys behindthe work.
Our business and corporate attorneys handle this work alongside our litigation team, so you have coverage whether your matter stays transactional or becomes something more.
What clientsask us first.
How do we establish paternity in Washington?
Three main ways. Both parents can sign a voluntary Acknowledgment of Parentage, which under RCW 26.26A.200 carries the force of a court order. Parentage can be presumed, usually through marriage. Or, if it's disputed, a court can adjudicate it, often using genetic testing. Which path fits depends on your situation, and we'll tell you the cleanest one.
We signed an acknowledgment at the hospital. Is that enough?
Usually, yes. A signed Acknowledgment of Parentage is legally binding and, after a short window, becomes the equivalent of a court order establishing the parent-child relationship. You can rescind it within 60 days. After that, it can only be challenged on narrow grounds like fraud or mistake. For most families, the acknowledgment is all the establishment they need.
Can parentage be challenged or undone?
Sometimes, within limits. Genetic testing under RCW 26.26A.300 answers the biological question, but the law sets time limits and narrow grounds for undoing an established parentage, especially once an acknowledgment has become final or a presumption has set in. The sooner a question is raised, the more options exist. We assess whether a challenge is realistic before anyone spends money on it.
Does an unmarried father have custody rights?
Not until parentage is established. Once it is, an unmarried father has the same standing as any parent to seek a parenting plan and child support under RCW 26.09 and RCW 26.19. Establishing parentage is the step that converts a biological relationship into legal rights and responsibilities, so it's where these cases start.
We're a same-sex couple, or used assisted reproduction. How do we both become legal parents?
Washington's Parentage Act provides several routes, including the marital presumption, a signed acknowledgment, de facto parentage under RCW 26.26A.440, and the assisted-reproduction provisions under RCW 26.26A.600. Because other states don't always honor those routes equally, we often recommend a confirmatory adoption as a belt-and-suspenders step that's recognized everywhere. We help both parents get securely on the legal record.
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Tell us about your family and what you need to establish or resolve. A family law attorney will follow up within one business day, and the first conversation is confidential.
Oseran Hahn P.S. · 11225 SE 6th St, Suite 100 · Bellevue, WA 98004
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