Reciprocity.

RCW 26.60.090
in effect
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A legal union, other than a marriage, of two persons that was validly formed in another jurisdiction, and that is substantially equivalent to a domestic partnership under this chapter, shall be recognized as a valid domestic partnership in this state and shall be treated the same as a domestic partnership registered in this state regardless of whether it bears the name domestic partnership. A legal union, other than a marriage, of two persons that was validly formed in another jurisdiction, and that is substantially equivalent to a domestic partnership under this chapter, shall be recognized as a valid domestic partnership in this state and shall be treated the same as a domestic partnership registered in this state regardless of whether it bears the name domestic partnership.
Source: WA Statutes (Official Site)URL: https://app.leg.wa.gov/RCW/default.aspx?cite=26.60&full=trueFetched: 6/29/2026

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