Boundary Atlas

ZIP code 50156: Madrid, IA

ZIP code 50156 is in Madrid (60% of residents), in Boone County (87%), Polk County (9.8%) and Dallas County (3.7%), Iowa. 40% of its residents live outside city limits. It is in Iowa's 4th congressional district (87%) and Iowa's 3rd congressional district (13%). Its state senate districts are State Senate District 24 (87%) and State Senate District 23 (13%); its state house districts are State House District 48 (87%), State House District 45 (9.8%) and State House District 46 (3.7%).

4,662residents (2020 Census)
88.5 sq miland area
2cities and towns
2congressional districts
9voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
Madrid60%
Luther0.2%

CountyShare of ZIP residents
Boone County87%
Polk County9.8%
Dallas County3.7%

Town or county subdivisionShare of ZIP residents
Douglas township56%
Garden township25%
Union township5.5%
Jefferson township4.2%
Worth township4.1%
Des Moines township3.7%
Colfax township1.6%
Madison township0.1%
Saylorville Reservoir UTland only

Congressional districts

Congressional districtShare of ZIP residents
Iowa's 4th congressional district (IA-04)87%
Iowa's 3rd congressional district (IA-03)13%

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-04)Randy Feenstra (R)202-225-442687%
U.S. Representative (IA-03)Zachary Nunn (R)202-225-547613%
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 24)Jesse Green (R)87%
State Senator (State Senate District 23)Jack Whitver (R)13%
State Representative (State House District 48)Chad Behn (R)87%
State Representative (State House District 45)Brian Lohse (R)9.8%
State Representative (State House District 46)Dan Gehlbach (R)3.7%

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 2487%
State Senate District 2313%

State house districtShare of ZIP residents
State House District 4887%
State House District 459.8%
State House District 463.7%

Voting precincts

9 voting precincts overlap ZIP 50156. Map them, with each precinct's share of the ZIP's residents.

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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:50156")

ZIP 50156 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.