Voters do not register for a political party in the state of Washington.
Party affiliation not required when registering to vote.
Under no circumstances may an individual be required to affiliate with, join, adhere to, express faith in, or declare a preference for, a political party or organization upon registering to vote.
Party affiliation is required on the return ballot envelope to participate in the nomination process during the March Presidential Primary.
FAQ: Why does the ballot say that a candidate "prefers" a certain party?
According to WAC 434-208-130:
(2) As allowed by WAC 434-215-012, 434-215-120, and 434-215-130, candidates for partisan office may state a preference for any political party and are not restricted to stating a preference for a political party that meets the definition of major or minor political party. A candidate's party preference does not imply that the candidate is nominated or endorsed by that party, or that the party approves of or associates with that candidate. With the exception of elections for president and vice president, a party's status as a major or minor political party, or a candidate's preference for a major or minor political party, plays no role in how candidates qualify to appear on the primary election ballot, qualify to appear on the general election ballot, or are elected to public office.