Boundary Atlas

Iowa's 4th congressional district (IA-04)

Iowa's 4th congressional district (IA-04) covers parts or all of 36 counties, including Audubon County, Boone County, Buena Vista County, Calhoun County, Carroll County and Cherokee County, and 392 ZIP codes (326 wholly inside it). Its 2020 population was 797,645. This is the map in force for the November 3, 2026 election.

797,645residents (2020 Census)
36counties
392ZIP codes
466voting precincts

Who represents IA-04

OfficeMemberContact
U.S. Representative (IA-04)Randy Feenstra (R)202-225-4426
U.S. SenatorChuck Grassley (R)202-224-3744 · contact form
U.S. SenatorJoni Ernst (R)202-224-3254 · contact form

Officials serving now (members of Congress until January 3, 2027). Sources: Members of Congress: the @unitedstates project, congress-legislators (CC0).

Counties

CountyShare of the county's residents in IA-04
Audubon County100%
Boone County100%
Buena Vista County100%
Calhoun County100%
Carroll County100%
Cherokee County100%
Clay County100%
Crawford County100%
Dickinson County100%
Emmet County100%
Franklin County100%
Fremont County100%
Hamilton County100%
Hancock County100%
Harrison County100%
Humboldt County100%
Ida County100%
Kossuth County100%
Lyon County100%
Marshall County100%
Mills County100%
Monona County100%
O'Brien County100%
Osceola County100%
Palo Alto County100%
Plymouth County100%
Pocahontas County100%
Pottawattamie County100%
Sac County100%
Shelby County100%
Sioux County100%
Story County100%
Webster County100%
Winnebago County100%
Woodbury County100%
Wright County100%

ZIP codes

Percentages mark ZIPs only partly in IA-04: the share of that ZIP's residents inside it.

Towns

Afton township, Algona city, Allen township, Allison township, Allison township, Amaqua township, America township, Amherst township, Amsterdam township, Anderson township, Arcadia township, Arlington township, Armstrong Grove township, Ashton township, Audubon township, Avery township, Avery township, Badger township, Baker township, Baker township, Bangor township, Banner township, Barnes township, Battle township, Beaver township, Beaver township, Belknap township, Bellville township, Belmond township, Belvidere township, Benton township, Bingham township, Blaine township, Blaine township, Blairsburg township, Boomer township, Boone township, Boone township, Booth township and Boyer Valley township and others.

Get this in your AI agent

Your agent can draw every precinct in IA-04, or list them with population shares (related_geographies). Add https://boundarymcp.com/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

get_boundaries(id="us:congressional_district:1904", children_level="precinct", include_districts=True)