Annexation is the process by which a city or a village acquires unincorporated territory from a neighboring town, and is governed by Wis. Stats. Ch. 66.  The residents of unincorporated territory may petition the governing body of a contiguous city or village for “Direct Annexation” or “Annexation by Referendum” of the territory into the city or village.  A city council or village board may also initiate annexation in several different ways, including passing an ordinance to annex a town island or territory owned by the city or village, or by passing a resolution to apply to a circuit court for approval to conduct an annexation referendum.  Neighboring municipalities may also resolve a boundary dispute by a stipulation which results in property being annexed to a city or village.  The result of any of these procedures is that new territory becomes a part of the annexing municipality.

A completed annexation changes the boundaries of the municipality gaining territory and the municipality losing territory.  Annexation may introduce new districts to the municipality gaining territory or eliminate districts in the municipality losing territory.  While the focus of annexation by governing bodies is often accommodating future development on property that may be currently vacant, the clerks of both municipalities must be aware of the effect the annexation will have on elections and representation in their respective municipalities.

For more information regarding the various methods of annexation, please refer to the “Annexation Methods” page on the Intergovernmental Relations Division’s portion of the Wisconsin Department of Administration website.

Annexation and Polling Places

If the municipality annexing the territory is required to create a new ward because of differing districts, the municipality’s governing body may adopt a resolution, pursuant to Wis. Stat. § 5.15(6)(b), combining the new ward with existing wards for purposes of voting at a common polling place.  A new polling place would not be required.  If the annexed territory were absorbed into an existing ward, every voter in the newly-configured ward must vote at the same polling place because every voter in any ward has to vote at the same polling place.

Notifying Governmental Units and Other Entities of Annexation

Annexation is not a process performed in a vacuum.  It is important for municipal clerks to reach out to other affected entities and keep them informed throughout the annexation process.  Conversely, the municipal clerks can expect to be contacted by other agencies such as the Wisconsin Departments of Revenue (DOR), Public Instruction (DPI), Transportation (DOT) and Agriculture, Trade and Consumer Protection (DATCP).

Pursuant to Wis. Stat. § 5.05(15) and to facilitate communication to the WEC with respect to annexations, WEC staff has developed the Annexation Checklist & Ward/Voter Information Sheet (EL-100).  The EL-100 includes a guide to election administration and WISVOTE processes required upon completion of a successful annexation.  This checklist and guide will help to ensure correct processes are followed, and voters are accurately represented within WISVOTE.

When Annexation Necessitates the Creation of a New Ward

As mentioned earlier, wards are the smallest units from which congressional, assembly, county supervisory and aldermanic districts are created.  A single ward may contain only one of each of these types of districts.  All territory, even if unpopulated, must be contained in a ward.  Wis. Stat. § 5.15(1)(b) and (6)(a).

This basic principle also applies to annexation.  The municipality annexing the territory may “absorb” the annexed territory into an existing, contiguous ward only if the annexed territory is in the same congressional, assembly and county supervisory districts as the ward to which it is added.  If the congressional, assembly or county supervisory districts in the annexed territory are different from the districts in the ward to which the territory is contiguous, a new ward must be created for the annexed territory. Wis. Stat. § 5.15(7).  Territory cannot be added to an existing non-contiguous ward, regardless of district composition, except in the case of “Island Territory.” Island territory is defined as “…territory surrounded by water, or noncontiguous territory which is separated by the territory of another municipality or by water, or both, from the major part of the municipality to which it belongs.” Wis. Stat. § 5.15(2)(f) 3.




Determining Where Annexed Electors Vote

The annexed territory becomes part of the municipality annexing the territory.  If the territory is able to be absorbed into an existing ward, voters in the newly-annexed territory will vote in the same municipal district (town, city aldermanic, or village trustee in a few cases) as the other voters in the ward.  If a new ward is created, the new residents vote in the municipal district to which they are assigned.  Regardless of whether a new ward is required or not, newly-annexed residents will continue to vote in the same congressional, state senate and assembly district as they did before the annexation.  Wis. Stat. § 5.15(7).  Whether the newly-annexed residents continue to vote in the same county supervisory district depends on whether the county adopts a revised division ordinance moving the annexed territory into the same supervisory district as the ward to which it is annexed.  Wis. Stat. § 59.10(3)(c).

Transferring Voters

The clerk of the municipality losing territory must photocopy each of the original Voter Registration Applications (EL-131s) and current absentee ballot applications of the voters residing in the annexed territory.  Each photocopy is marked “transferred.”  If the municipality has adopted the records retention periods set forth in Wis. Stat. § 7.23, the photocopied Voter Registration Applications are marked for final disposition four years from the effective date of the annexation, and the photocopied absentee ballot applications are marked for destruction 90 days (non-federal election) or 22 months (federal election) from the date of the most recent election to which the absentee ballot applications applied.  If the municipality has adopted longer records retention periods than those specified in Wis. Stat. § 7.23, the Voter Registration Applications and absentee ballot applications are marked for final disposition consistent with such other specified records retention period policy.

The original forms are forwarded to the clerk of the municipality gaining the territory.  When the clerk of the municipality who has lost voters forwards a valid absentee ballot request to the clerk who has gained the voters, the “gaining” clerk should honor the request for subsequent elections as requested by the voter.

The clerk of the “gaining” municipality must notify the newly-annexed voters of the location of their new polling place, ward number and voting districts.

The following agencies must be notified of annexations:




  • Approved Annexation Ordinance
  • Completed Annexation Checklist and Ward\Voter Information Sheet (EL-100)

WI Dept. of Administration (D.O.A.)


Required to review annexations when:

  • The annexed territory is in a county with a population of 50,000 or more.
  • The annexation petition is either a unanimous consent or one-half approval type of annexation.

Annexation, Attachment, Detachment Ordinances must contain:

  • Clerk’s certification that the documents are true and correct copies of originals and bear the clerk’s signature.
  • Copy of the ordinance, which must include population of the property being transferred, scale map of the property showing it proximity to the current boundary of the annexing municipality, legal description of the property being transferred, and ordinance effective date.

Contact D.O.A. Division of Intergovernmental Relations, Municipal Boundary Review for more information.

Affected School Districts

Copy of approved annexation ordinance

County Register of Deeds

Copy of approved annexation ordinance

Area Utilities

Copy of approved annexation ordinance

Municipal clerks should always involve the municipal attorney during the annexation process, or consult the Wisconsin Towns Association or League of Wisconsin Municipalities about procedural or legal questions.

Frequently Asked Questions

    Wis. Stat. § 5.15(6)(a) provides “…no ward line adjustment may cross the boundary of a congressional, assembly or supervisory district…”  There is no provision in state law that exempts unpopulated territory from this requirement.  Ensuring proper ward designation at the time of annexation prevents confusion if vacant land subsequently becomes populated.

    With the exception of island territory, the answer is “no.”  Property cannot be made part of an existing ward if it is not contiguous to that ward.  Annexed territory can only be absorbed into an existing ward if:


    • the territory being annexed is contiguous to the ward, and
    • the districts of the annexed territory are the same as the contiguous ward.


         Wis. Stat. § 5.15(1)(b) and (7).

    No.  A new ward is not required to be created if the districts of the annexed territory are identical to the contiguous ward, except for differing school districts.  Wis. Stat. § 5.15(6)(a).

    Yes.  Even though the annexed territory may be absorbed into the contiguous ward, the governing body may choose to make the territory a new ward and aldermanic district when population growth is expected.  Wis. Stat. § 5.15(1)(a)1. and (2)(f)4.

    No.  A new ward must be created.  The voters in the annexed territory remain in the Supervisory District in which they voted before the annexation unless the county board of supervisors redraws county supervisory district boundary lines to include those voters.  Wis. Stat. § 59.10(c).