A candidate desiring to file as a write-in candidate must file the write-in declaration of candidacy no later than 8:00 p.m. on election day. If a write-in declaration of candidacy is filed with the filing officer after the close of the regular candidate filing period per RCW 29A.24.050 and more than 18 days before a primary or election, no filing fee is required.

Candidates filing a write-in declaration of candidacy on or after the 18th day before a primary or election must pay a filing fee at the time of filing the declaration. Offices with a fixed annual salary of more than $1,000 must pay a filing fee equal to one percent of the annual salary at the time of the regular filing period as per RCW 29A.24.091. For all other offices, a filing fee of $25 is required.