(1) The legislative body of any county planning under chapter 36.70A RCW and subject to the requirements of RCW 36.70A.215 may initiate an annexation process with the legislative body of any other cities or towns that are contiguous to the territory proposed for annexation in RCW 35.13.470 if:

(a) The county legislative body initiated an annexation process as provided in RCW 35.13.470; and

(b) The affected city or town legislative body adopted a responsive resolution rejecting the proposed annexation or declined to create the requested interlocal agreement with the county; or

(c) More than one hundred eighty days have passed since adoption of a county resolution as provided for in RCW 35.13.470 and the parties have not adopted or executed an interlocal agreement providing for the annexation of unincorporated territory. The legislative body for either the county or an affected city or town may, however, pass a resolution extending the negotiation period for one or more six-month periods if a public hearing is held and findings of fact are made prior to each extension.

(2) Any county initiating the process provided for in subsection (1) of this section must do so by adopting a resolution commencing negotiations for an interlocal agreement as provided in chapter 39.34 RCW between the county and any city or town within the county. The annexation area must be within an urban growth area designated under RCW 36.70A.110 and at least sixty percent of the boundaries of the territory to be annexed must be contiguous to one or more cities or towns.

(3) The agreement shall describe the boundaries of the territory to be annexed. A public hearing shall be held by each legislative body, separately or jointly, before the agreement is executed. Each legislative body holding a public hearing shall, separately or jointly, publish the agreement at least once a week for two weeks before the date of the hearing in one or more newspapers of general circulation within the territory proposed for annexation.

(4) Following adoption and execution of the agreement by both legislative bodies, the city or town legislative body shall adopt an ordinance providing for the annexation. The legislative body shall cause notice of the proposed effective date of the annexation, together with a description of the property to be annexed, to be published at least once each week for two weeks subsequent to passage of the ordinance, in one or more newspapers of general circulation within the city and in one or more newspapers of general circulation within the territory to be annexed. If the annexation ordinance provides for assumption of indebtedness or adoption of a proposed zoning regulation, the notice shall include a statement of the requirements. Any area to be annexed through an ordinance adopted under this section is annexed and becomes a part of the city or town upon the date fixed in the ordinance of annexation, which date may not be less than forty-five days after adoption of the ordinance.

(5) The annexation ordinances provided for in *RCW 35.13.470(4) and subsection (4) of this section are subject to referendum for forty-five days after passage. Upon the filing of a timely and sufficient referendum petition with the legislative body, signed by registered voters in number equal to not less than fifteen percent of the votes cast in the last general state election in the area to be annexed, the question of annexation shall be submitted to the voters of the area in a general election if one is to be held within ninety days or at a special election called for that purpose according to RCW 29A.04.330. Notice of the election shall be given as provided in RCW 35.13.080 and the election shall be conducted as provided in the general election law. The annexation shall be deemed approved by the voters unless a majority of the votes cast on the proposition are in opposition thereto.

After the expiration of the forty-fifth day from but excluding the date of passage of the annexation ordinance, if no timely and sufficient referendum petition has been filed, the area annexed shall become a part of the city or town upon the date fixed in the ordinance of annexation.

(6) If more than one city or town adopts interlocal agreements providing for annexation of the same unincorporated territory as provided by this section, an election shall be held in the area to be annexed pursuant to RCW 35.13.070 and 35.13.080. In addition to the provisions of RCW 35.13.070 and 35.13.080, the ballot shall also contain a separate proposition allowing voters to cast votes in favor of annexation to any one city or town participating in an interlocal agreement as provided by this section. If a majority of voters voting on the proposition vote against annexation, the proposition is defeated. If, however, a majority of voters voting in the election approve annexation, the area shall be annexed to the city or town receiving the highest number of votes among those cast in favor of annexation.

(7) Costs for an election required under subsection (6) of this section shall be borne by the county.

*Reviser’s note: RCW 35.13.470 was amended by 2023 c 351 § 1, changing subsection (4) to subsection (5).

Effective date—2006 c 344 §§ 1-16 and 18-40: See note following RCW 29A.04.311.