Boundary Atlas

ZIP code 62864: Mount Vernon, IL

ZIP code 62864 is in Mount Vernon (63% of residents), in Jefferson County, Illinois. 37% of its residents live outside city limits. It is in Illinois's 12th congressional district. Its state senate district is State Senate District 58; its state house district is State House District 116.

23,327residents (2020 Census)
143.0 sq miland area
1cities and towns
1congressional district
23voting precincts

See it on the mapAll of Illinois

City and county

City or townShare of ZIP residents
Mount Vernon63%

CountyShare of ZIP residents
Jefferson County100%

Town or county subdivisionShare of ZIP residents
Mount Vernon township54%
Shiloh township25%
Dodds township9.6%
McClellan township4.1%
Field township3.5%
Webber township2.1%
Rome township1.7%
Farrington township0.2%

Congressional district

Congressional districtShare of ZIP residents
Illinois's 12th congressional district (IL-12)100%

State legislative districts

State senate districtShare of ZIP residents
State Senate District 58100%

State house districtShare of ZIP residents
State House District 116100%

Voting precincts

23 voting precincts overlap ZIP 62864. 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:62864")

ZIP 62864 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.