Janesville, Illinois
Janesville is a Census-designated place (an unincorporated community) in Coles County (62% of residents) and Cumberland County (38%), Illinois, with 76 residents in 2020. It is in Illinois's 12th congressional district. It spans 2 state house districts. Its state senate district is State Senate District 51.
County
| County | Share of residents |
|---|---|
| Coles County | 62% |
| Cumberland County | 38% |
Congressional district
| Congressional district | Share of residents |
|---|---|
| Illinois's 12th congressional district (IL-12) | 100% |
Elected officials
| Office | Member | Contact | Share of residents |
|---|---|---|---|
| U.S. Representative (IL-12) | Mike Bost (R) | 202-225-5661 | 100% |
| U.S. Senator | Richard J. Durbin (D) | 202-224-2152 · contact form | statewide |
| U.S. Senator | Tammy Duckworth (D) | 202-224-2854 · contact form | statewide |
| State Senator (State Senate District 51) | Chapin Rose (R) | 217-607-1853 | 100% |
| State Representative (State House District 101) | Chris Miller (R) | 217-508-4108 | 62% |
| State Representative (State House District 102) | Adam Niemerg (R) | 217-712-2126 | 38% |
Officials serving now (members of Congress until January 3, 2027). Sources: State legislators: Open States (public domain); Members of Congress: the @unitedstates project, congress-legislators (CC0).
Local government
- Janesville laws: search for the Janesville, Illinois code of ordinances
- Coles County laws: search for the Coles County, Illinois code of ordinances
- Cumberland County website: http://www.cumberlandco.org
- Cumberland County laws: search for the Cumberland County, Illinois code of ordinances
State legislative districts
| State senate district | Share of residents |
|---|---|
| State Senate District 51 | 100% |
| State house district | Share of residents |
|---|---|
| State House District 101 | 62% |
| State House District 102 | 38% |
ZIP codes
Percentages mark ZIPs only partly in Janesville: the share of that ZIP's residents living in it.
- 62440 (6.8%)
Get this in your AI agent
Your agent can get Janesville's counties and districts with shares, its ZIP codes (level='zcta'), and its boundary as GeoJSON (get_boundaries). Add https://boundarymcp.com/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
related_geographies(id="us:place:1738232")
Janesville here is the Census Bureau's place boundary as of January 1, 2025 (a Census-designated place, which has no municipal government). Shares are of 2020 Census population. Districts are the maps in force for the November 3, 2026 election.