Boundary Atlas

Iowa's 1st congressional district (IA-01)

Iowa's 1st congressional district (IA-01) covers parts or all of 20 counties, including Cedar County, Clinton County, Des Moines County, Henry County, Iowa County and Jackson County, and 249 ZIP codes (185 wholly inside it). Its 2020 population was 797,584. This is the map in force for the November 3, 2026 election.

797,584residents (2020 Census)
20counties
249ZIP codes
408voting precincts

Who represents IA-01

OfficeMemberContact
U.S. Representative (IA-01)Mariannette Miller-Meeks (R)202-225-6576
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-01
Cedar County100%
Clinton County100%
Des Moines County100%
Henry County100%
Iowa County100%
Jackson County100%
Jasper County100%
Jefferson County100%
Johnson County100%
Jones County100%
Keokuk County100%
Lee County100%
Louisa County100%
Mahaska County100%
Marion County100%
Muscatine County100%
Scott County100%
Van Buren County100%
Warren County100%
Washington County100%

ZIP codes

Percentages mark ZIPs only partly in IA-01: the share of that ZIP's residents inside it.

Towns

Adams township, Adams township, Allen township, Allens Grove township, Baltimore township, Bellevue township, Belmont township, Benton township, Benton township, Big Grove township, Black Hawk township, Black Oak township, Bloomfield township, Bloomington township, Blue Grass township, Bonaparte township, Brandon township, Brighton township, Brookfield township, Buchanan township, Buena Vista township, Buffalo township, Burlington city, Butler township, Butler township, Camanche township, Canaan township, Cass township, Cass township, Castle Grove township, Cedar township, Cedar township, Cedar township, Cedar township, Cedar township, Cedar township, Cedar township, Center township, Center township and Center township and others.

Get this in your AI agent

Your agent can draw every precinct in IA-01, 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:1901", children_level="precinct", include_districts=True)