Polygamy is not legal in Washington State. Marrying a second person while you still have a living spouse is a Class C felony called bigamy, punishable by up to five years in prison and a $10,000 fine.1Washington State Legislature. RCW 9A.64.010 – Bigamy Washington defines marriage as a civil contract between two people, and the state refuses to recognize polygamous marriages performed anywhere else.2Washington State Legislature. RCW 26.04.010 – Marriage Contract
What Counts as Bigamy
Washington’s bigamy statute reaches anyone who intentionally marries, or claims to marry, another person while either party has a living spouse.1Washington State Legislature. RCW 9A.64.010 – Bigamy Two features of that language catch people off guard. The word “purports” means a legally valid ceremony is not required; going through the motions of a wedding while already married is enough. And the law captures both sides, so knowingly marrying someone who already has a spouse is also bigamy.
A marriage license from a Washington county auditor requires that both parties be legally eligible, which means any prior marriage must already be ended by a final decree of dissolution, an annulment, or the death of the earlier spouse.3Washington State Legislature. RCW 26.04 – Marriage A state-registered domestic partnership with someone else counts too.
The statute requires intent. Marrying someone who turns out to be already married, with no reason to know, is not bigamy on your part. The prosecution can still try to show you knew the facts that made the marriage illegal.
Penalties and How Long You Can Be Charged
Bigamy is a Class C felony. The sentencing ceiling is up to five years of confinement, a fine of up to $10,000, or both.4Washington State Legislature. RCW 9A.20.021 – Maximum Sentences for Crimes Committed July 1, 1984, and After A felony conviction also carries lasting collateral effects on employment, professional licensing, and firearm ownership.
The limitation period is where bigamy differs from most other Class C felonies. The ordinary three-year clock does not start when the second marriage happens.5Washington State Legislature. RCW 9A.04.080 – Prosecution – Limitation of Actions Under the bigamy statute, it starts only when one of the spouses dies or a court enters a judgment terminating one of the marriages.1Washington State Legislature. RCW 9A.64.010 – Bigamy As a practical matter, the state can bring a bigamy charge decades after the second wedding, as long as both spouses are living and neither marriage has been dissolved.
Defenses the Statute Allows
Three affirmative defenses are written into the bigamy law. Any one of them, if established, defeats the charge:1Washington State Legislature. RCW 9A.64.010 – Bigamy
- You reasonably believed your prior spouse was dead. A long disappearance with no contact can support this, but the standard is reasonableness, not hope.
- You relied on a court judgment that appeared to dissolve or annul the earlier marriage and did not know the judgment was legally defective. This comes up when a divorce decree is later overturned on procedural grounds.
- You reasonably believed you were legally eligible to marry, even if that belief turned out to be wrong.
Once you raise one of these defenses, the prosecution bears the burden of disproving it. The state can still prevail by showing you actually knew the facts that made the new marriage illegal, even if you misunderstood the legal consequences of those facts.
Marriages From Other States and Countries
Washington usually honors marriages validly performed elsewhere, but polygamous unions are a firm exception. A foreign or out-of-state marriage is recognized in Washington only if it does not violate the state’s prohibition on marrying while you already have a living spouse.3Washington State Legislature. RCW 26.04 – Marriage The Washington Attorney General’s office has taken the same position, confirming that marriages violating the bigamy or domestic partnership prohibitions will not be recognized.6Washington State Attorney General. Validity of Marriages Abroad and Foreign Divorces in Washington State
If you move to Washington from a country that permits plural marriage, only your first marriage is recognized. Additional spouses have no legal standing for community property claims, inheritance, insurance coverage, or healthcare decisions. In probate, if the partner dies without a will, only the legally recognized spouse has a statutory claim to the estate.
Federal Immigration Consequences
Immigration law adds a separate layer of risk. The Immigration and Nationality Act makes any immigrant coming to the United States to practice polygamy inadmissible, which can block a visa at the application stage.7Office of the Law Revision Counsel. 8 USC 1182 – Inadmissible Aliens
Practicing polygamy after receiving a green card can lead to deportation. For naturalization, polygamy undermines the “good moral character” requirement citizenship applicants must meet. An applicant who has practiced polygamy generally needs to end all polygamous relationships and wait five years before the good moral character period can begin. Holding a belief in polygamy is not itself disqualifying; actively practicing it is what creates the barrier.
Children and Spouses When a Marriage Is Declared Invalid
When a Washington court declares a marriage invalid because of bigamy, children and deceived spouses are not left without protection.
Children born or conceived during a marriage later declared invalid are considered legitimate. The court must enter custody and support orders exactly as it would in a standard divorce.8Washington State Legislature. RCW 26.09.040 – Petition to Have Marriage or Domestic Partnership Declared Invalid A child’s right to support from both parents does not depend on the parents’ marriage being valid.
A spouse who entered the marriage without knowing about the prior one may still be eligible for maintenance. Washington courts can award spousal support to a party who entered the marriage in good faith, using the same factors applied in standard divorce proceedings.8Washington State Legislature. RCW 26.09.040 – Petition to Have Marriage or Domestic Partnership Declared Invalid Whether broader “putative spouse” property rights apply in Washington bigamy cases is less settled and depends on the facts. The safer route for a good-faith spouse is to petition for a formal declaration of invalidity and request equitable property division in that proceeding.
Polyamory Is Not the Same as Polygamy
Washington’s bigamy law targets formal legal acts: obtaining a marriage license or going through a wedding while you already have a spouse. It does not criminalize having multiple romantic partners, cohabiting with more than one partner, or maintaining polyamorous relationships. The line sits at the marriage license or domestic partnership registration.
Sharing a home and finances with multiple partners is not a crime under state law. What is prohibited is obtaining marriage licenses with more than one person at the same time, or holding yourself out as married to multiple people through a ceremony while a prior marriage is still active.