Municipal Incorporation

Overview

Under current Washington law, an area can incorporate as a city or town if:

• It has at least 1,500 inhabitants.
• It has at least 3,000 inhabitants and is within five air miles of the boundaries of a city or town with a population of 15,000 or more.

HIstorically, an area within five air miles of the boundaries of a city or town with a population of 15,000 or more needed at least 3,000 inhabitants to incorporate, but that changed in 2023 with the passage of HB 1620. From July 23, 2023, to June 30, 2028, an area with at least 1,500 inhabitants that lies within five air miles of a city or town of 15,000 or more may incorporate. After June 30, 2028, the provision will revert back to the original requirement of 3,000 inhabitants to incorporate.

The basic incorporation procedure is outlined in RCW 35.02, which includes a petition, review by a boundary review board or the county legislative body (in counties without boards), and an election. If the voters approve the proposed incorporation, a primary election to nominate candidates for council/mayor, and then an election must be held. The new city or town must officially incorporate at a date set by the initial council and within 360 days of the incorporation election.

After a few incorporations in the 1970s and 1980s, incorporation activity surged in the 1990s, especially in the Puget Sound region. For information about cities that have incorporated since 1970, visit our City and Town Forms of Government topic page.

Statutes

• Washington State Constitution Article XI, Sec. 10 – Establishes the basic authority for cities and towns to incorporate and for the state legislature to enact laws to govern the process of incorporation.
• Ch. 35.02 RCW – Contains the basic statutory procedures for incorporation in Washington State. It also establishes the legal authority and power of a city or town during the 'interim period', the period between the election of the initial governing body and the official date of incorporation. In addition, it addresses issues relating to the continued provision of municipal services after incorporation.
• Ch. 36.93 RCW – Provides the procedures and guidelines for boundary review board review of incorporations and of other processes, such as annexations, which alter municipal boundaries. Proposed incorporations are reviewed by a boundary review board in counties in which boards have been established. According to the Washington State Association of Boundary Review Boards, 14 of the state's 39 counties have boundary review boards.

Incorporation Feasibility Studies

Feasibility studies are an important tool used by local government and the public to evaluate the viability of a proposed incorporation. They typically include an analysis of population growth, potential geographic boundaries, level of services, and financial impacts. A feasibility study may also evaluate alternative proposals, including the potential incorporation of a new area or annexation into another existing municipality.

Examples of Incorporation Feasibility Studies

• King County: Fairwood Study Area – Various governance options were evaluated, including annexation by the City of Renton, incorporating to become the City of Fairwood, or staying unincorporated, all of which are explored in linked materials
  • Ordinance 16616  (2009)
  • Incorporation Study (2009)
  • Analysis of the Financial Feasibility of the Proposed City (2006)
• Pierce County: South Hill – Various governance options were evaluated, including incorporation for South Hill or annexation by the City of Puyallup
  • Incorporation Study or Annexation of South Hill  (2023)
• Spokane Valley
  • Incorporation Study (2001)
  • New City Summary (2002)
  • Interim Period Schedule of Actions (2004)
• Whatcom County: Birch Bay
  • Birch Bay Incorporation Feasibility Study (2025) – Updates the original 2008 study

Examples of Miscellaneous Incorporation Documents

• King County Boundary Review Board
  • Files – Includes links to all submitted Notices of Intention
  • Notice of Intention Information Packet (2013) – Offers directions to applicants submitting notices
• Proposed City of Sammamish: Incorporation Petition
• Spokane Valley: Notice of Incorporation (2000)

Washington State Attorney General Opinion

RCW 35.02.078 provides for an election on the question of incorporation of a city or town. The new entity does not exist until the date of incorporation. Since the election of officials by statute must occur prior to the incorporation date, that election cannot be a city/town election. Thus, under the analysis set forth in AGO 1967 No. 18, a city/town may not be held liable for the costs of the officials’ election. See AGO 1990 No. 14.

Disincorporation

RCW 35.07 outlines the disincorporation process for a municipal entity, which can happen voluntarily or involuntarily.

Pursuant to RCW 35.07.230-260, a town can be involuntarily disincorporated if:

• It fails to hold regular municipal elections for two years in a row; or
• If officers elected to the town council fail to qualify for two years in a row and the town ceases to function because it lacks a governing body.

Alternatively, a voluntary disincorporation can be initiated through a petition signed by a majority of the municipality’s registered voters (RCW 35.07.020). The city or town council then calls an election on the issue. (Note that pursuant to RCW 35.07.040, if the city or town has any indebtedness or outstanding liabilities, it must order the election of a receiver at the same time.)

A non-charter code city council may also initiate the disincorporation process pursuant to RCW 35A.15.010.

Examples of Documents Related to Disincorporation

• Gold Bar Res. No. 12-08 (2012) – Proposed unsuccessful disincorporation
• Spokane Valley Memo on Disincorporation (2009) – Offers a summary of methods for disincorporation