Washington Revised Code Title 72. State Institutions § 72.66.016. Minimum time served requirement

(a) If his or her minimum term of imprisonment is longer than twelve months, he or she shall have served at least six months of the term;

(b) If his or her minimum term of imprisonment is less than twelve months, he or she shall have served at least ninety days and shall have no longer than six months left to serve on his or her minimum term;

(c) If he or she is serving a mandatory minimum term of confinement, he or she shall have served all but the last six months of such term.