Wash. Rev. Code § 35A.14.120
Proceedings for initiating annexation of unincorporated territory to a charter code city or noncharter code city may be commenced by the filing of a petition of property owners of the territory proposed to be annexed, in the following manner. This method of annexation shall be alternative to other methods provided in this chapter. Prior to the circulation of a petition for annexation, the initiating party or parties, who shall be the owners of not less than ten percent in value, according to the assessed valuation for general taxation of the property for which annexation is sought, shall notify the legislative body of the code city in writing of their intention to commence annexation proceedings. The legislative body shall set a date, not later than sixty days after the filing of the request, for a meeting with the initiating parties to determine whether the code city will accept, reject, or geographically modify the proposed annexation, whether it shall require the simultaneous adoption of a proposed zoning regulation, if such a proposal has been prepared and filed for the area to be annexed as provided for in RCW 35A.14.330 and 35A.14.340, and whether it shall require the assumption of all or of any portion of existing city indebtedness by the area to be annexed. If the legislative body requires the assumption of all or of any portion of indebtedness and/or the adoption of a proposed zoning regulation, it shall record this action in its minutes and the petition for annexation shall be so drawn as to clearly indicate these facts. Approval by the legislative body shall be a condition precedent to circulation of the petition. There shall be no appeal from the decision of the legislative body. A petition for annexation of an area contiguous to a code city may be filed with the legislative body of the municipality to which annexation is desired. It must be signed by the owners, as defined by RCW 35A.01.040(9) (a) through (d), of not less than sixty percent in value, according to the assessed valuation for general taxation of the property for which annexation is petitioned: PROVIDED, That a petition for annexation of an area having at least eighty percent of the boundaries of such area contiguous with a portion of the boundaries of the code city, not including that portion of the boundary of the area proposed to be annexed that is coterminous with a portion of the boundary between two counties in this state, need be signed by only the owners of not less than fifty percent in value according to the assessed valuation for general taxation of the property for which the annexation is petitioned. Such petition shall set forth a description of the property according to government legal subdivisions or legal plats and shall be accompanied by a map which outlines the boundaries of the property sought to be annexed. If the legislative body has required the assumption of all or any portion of city indebtedness by the area annexed or the adoption of a proposed zoning regulation, these facts, together with a quotation of the minute entry of such requirement, or requirements, shall also be set forth in the petition.
RCW 35A.14.120
Severability-1979 ex.s. c 124: See note following RCW 35A.14.015.
Sufficiency of petition in code city: RCW 35A.01.040.