Boundary Atlas

ZIP code 51243: Little Rock, IA

ZIP code 51243 is in Little Rock (59% of residents), in Lyon County (95%) and Osceola County (4.9%), Iowa. 41% of its residents live outside city limits. It is in Iowa's 4th congressional district. Its state senate districts are State Senate District 2 (95%) and State Senate District 3 (4.9%); its state house districts are State House District 4 (95%) and State House District 5 (4.9%).

742residents (2020 Census)
52.3 sq miland area
1cities and towns
1congressional district
3voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
Little Rock59%

CountyShare of ZIP residents
Lyon County95%
Osceola County4.9%

Town or county subdivisionShare of ZIP residents
Elgin township80%
Grant township14%
Viola township3.9%
Liberal township1.1%
West Holman township0.9%

Congressional district

Congressional districtShare of ZIP residents
Iowa's 4th congressional district (IA-04)100%

State legislative districts

State senate districtShare of ZIP residents
State Senate District 295%
State Senate District 34.9%

State house districtShare of ZIP residents
State House District 495%
State House District 54.9%

Voting precincts

3 voting precincts overlap ZIP 51243. 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:51243")

ZIP 51243 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.