Boundary Atlas

ZIP code 61523: Chillicothe, IL

ZIP code 61523 is in Chillicothe (56% of residents) and Rome (14%), in Peoria County (99%) and Marshall County (0.7%), Illinois. 30% of its residents live outside city limits. It is in Illinois's 16th congressional district. Its state senate districts are State Senate District 37 (85%) and State Senate District 53 (15%); its state house districts are State House District 73 (85%) and State House District 105 (15%).

10,951residents (2020 Census)
53.3 sq miland area
2cities and towns
1congressional district
17voting precincts

See it on the mapAll of Illinois

City and county

City or townShare of ZIP residents
Chillicothe56%
Rome14%

CountyShare of ZIP residents
Peoria County99%
Marshall County0.7%

Town or county subdivisionShare of ZIP residents
Chillicothe township74%
Medina township17%
Hallock township8.1%
La Prairie township0.4%
Steuben township0.3%

Congressional district

Congressional districtShare of ZIP residents
Illinois's 16th congressional district (IL-16)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IL-16)Darin LaHood (R)202-225-6201100%
U.S. SenatorRichard J. Durbin (D)202-224-2152 · contact formstatewide
U.S. SenatorTammy Duckworth (D)202-224-2854 · contact formstatewide
State Senator (State Senate District 37)Li Arellano (R)779-251-500385%
State Senator (State Senate District 53)Chris Balkema (R)815-844-917915%
State Representative (State House District 73)Ryan Spain (R)309-690-737385%
State Representative (State House District 105)Dennis Tipsword (R)815-844-934415%

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

State legislative districts

State senate districtShare of ZIP residents
State Senate District 3785%
State Senate District 5315%

State house districtShare of ZIP residents
State House District 7385%
State House District 10515%

Voting precincts

17 voting precincts overlap ZIP 61523. Map them, with each precinct's share of the ZIP's residents.

Get this in your AI agent

Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

related_geographies(id="us:zcta:61523")

ZIP 61523 here is the Census Bureau's ZIP Code Tabulation Area, which approximates the USPS ZIP Code; PO-box-only ZIPs have none. Districts are the maps in force for the November 3, 2026 election.