Boundary Atlas

ZIP code 64503: St. Joseph, MO

ZIP code 64503 is in St. Joseph (95% of residents), in Buchanan County, Missouri. It is in Missouri's 6th congressional district. Its state senate district is State Senate District 34; its state house districts are State House District 11 (79%), State House District 10 (17%) and State House District 13 (4.2%).

12,127residents (2020 Census)
14.5 sq miland area
1cities and towns
1congressional district
8voting precincts

See it on the mapAll of Missouri

City and county

City or townShare of ZIP residents
St. Joseph95%

CountyShare of ZIP residents
Buchanan County100%

Town or county subdivisionShare of ZIP residents
Washington township100%

Congressional district

Congressional districtShare of ZIP residents
Missouri's 6th congressional district (MO-06)100%

Members of Congress

OfficeMemberContact
U.S. Representative (MO-06)Sam Graves (R)202-225-7041
U.S. SenatorEric Schmitt (R)202-224-5721 · contact form
U.S. SenatorJosh Hawley (R)202-224-6154 · contact form

Members serving now (119th Congress, until January 3, 2027). Source: Members of Congress: the @unitedstates project, congress-legislators (CC0).

State legislative districts

State senate districtShare of ZIP residents
State Senate District 34100%

State house districtShare of ZIP residents
State House District 1179%
State House District 1017%
State House District 134.2%

Voting precincts

8 voting precincts overlap ZIP 64503. Map them, with each precinct's share of the ZIP's residents.

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ZIP 64503 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.