Boundary Atlas

ZIP code 50240: St. Charles, IA

ZIP code 50240 is in St. Charles (27% of residents), in Madison County (65%) and Warren County (35%), Iowa. 73% of its residents live outside city limits. It is in Iowa's 3rd congressional district (65%) and Iowa's 1st congressional district (35%). Its state senate districts are State Senate District 12 (65%) and State Senate District 11 (35%); its state house districts are State House District 23 (65%) and State House District 22 (35%).

2,399residents (2020 Census)
75.3 sq miland area
1cities and towns
2congressional districts
6voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
St. Charles27%

CountyShare of ZIP residents
Madison County65%
Warren County35%

Town or county subdivisionShare of ZIP residents
South township60%
Jackson township29%
Jefferson township5.7%
Scott township2.9%
Crawford township1.6%
Virginia township0.6%
Ohio township0.2%

Congressional districts

Congressional districtShare of ZIP residents
Iowa's 3rd congressional district (IA-03)65%
Iowa's 1st congressional district (IA-01)35%

This ZIP is split between districts. A mailing address in it could be in either; the map or locate_point gives the district for an exact address.

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IA-03)Zachary Nunn (R)202-225-547665%
U.S. Representative (IA-01)Mariannette Miller-Meeks (R)202-225-657635%
U.S. SenatorChuck Grassley (R)202-224-3744 · contact formstatewide
U.S. SenatorJoni Ernst (R)202-224-3254 · contact formstatewide
State Senator (State Senate District 12)Amy Sinclair (R)65%
State Representative (State House District 23)Bubba Sorensen (R)65%
State Representative (State House District 22)Samantha Fett (R)35%

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 1265%
State Senate District 1135%

State house districtShare of ZIP residents
State House District 2365%
State House District 2235%

Voting precincts

6 voting precincts overlap ZIP 50240. 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:50240")

ZIP 50240 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.