University of Illinois Urbana‑Champaign

Geographic Region: Municipalities

Found out about municipalities.

About the data

Incorporated places are those that are reported to the Census Bureau as legally in existence as of January 1 of a given year according to the latest Boundary and Annexation Survey, under the laws of their respective states. An incorporated place is established to provide governmental functions for a concentration of people as opposed to a county subdivision (see Geographic Region: Townships). Incorporated places always are within a single state but may extend across county and county subdivision boundaries. An incorporated place usually is a city, town, village, or borough, but can have other legal descriptions.

Source of definition: U.S. Census Bureau, Geography Division. Geographic Terms and Concepts: Place

In Illinois, three names are used for incorporated places: city, town, and village. IECAM uses the term municipality instead of incorporated place as an overriding term for these three types of places.

According to the U.S. Census, the requirements for incorporated places in Illinois are the following:

  • City. Minimum population requirement of 2,500; if located in Cook County, may incorporate with a minimum of 1,200 residents if the area consists of less than 4 square miles and contains all the registered voters of a township not already within the corporate limits of a municipality.
  • Town. No minimum population requirement.
  • Village. In counties with a population of at least 150,000, a minimum of 2,500 residents are required to incorporate; a minimum of 200 residents are required in other counties.

The number of municipalities in Illinois, as reported in census data, may vary slightly from year to year. The list of municipalities in Illinois periodically changes as old municipalities are dissolved, new municipalities are incorporated, municipalities undergo boundary changes, or municipalities change their names. Although the number of such changes is very small, nevertheless note that

  • the number of municipalities may change from year to year,
  • municipality X in one year may not cover the same geographic area as municipality X the following year, and
  • a municipality may not have the same name from one year to the next.

Almost all site-based data (e.g., child care) and almost all demographic data (e.g., population) are presented by municipality in IECAM. Non-site-based data (e.g., early intervention) are not presented by municipality.

When a user searches by year and by municipality in the basic search, IECAM presents results only for those municipalities that existed in that year. When a user searches by municipality and several years in the multiyear search, IECAM presents results for all municipalities that existed in any of the years selected. If the municipality did not exist in one of the selected years, an indication such as “N/A” will appear in that particular table cell.

  • A list of municipalities used in IECAM data

  • A list of municipalities used in IECAM data