Yes, cousin marriage is legal in Washington under specific conditions. State law permits first-cousin unions, but prohibits marriages between closer relatives (e.g., siblings, half-siblings). Local county auditors enforce these rules during license issuance, with no 2026 statutory changes altering the framework.
Key Regulations for Cousin Marriage in Washington
- First-cousin marriages are lawful under RCW 26.04.020, provided neither party is already married or within prohibited degrees of consanguinity.
- Prohibited unions include marriages between siblings, half-siblings, parents/children, or grandparents/grandchildren, as defined in RCW 26.04.010.
- County-level enforcement: Auditors in each of Washington’s 39 counties verify compliance during marriage license applications, referencing state statutes and case law (e.g., In re Marriage of Jorgensen, 1980).