Boundary Atlas

ZIP code 63473: Union, MO

ZIP code 63473 is in Williamstown (20% of residents), in Lewis County (52%) and Clark County (48%), Missouri. 80% of its residents live outside city limits. It is in Missouri's 6th congressional district. Its state senate district is State Senate District 18; its state house district is State House District 4.

301residents (2020 Census)
61.9 sq miland area
1cities and towns
1congressional district
4voting precincts

See it on the mapAll of Missouri

City and county

City or townShare of ZIP residents
Williamstown20%

CountyShare of ZIP residents
Lewis County52%
Clark County48%

Town or county subdivisionShare of ZIP residents
Union township38%
Reddish township37%
Lyon township15%
Washington township5.7%
Jackson township4.3%

Congressional district

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

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (MO-06)Sam Graves (R)202-225-7041100%
U.S. SenatorEric Schmitt (R)202-224-5721 · contact formstatewide
U.S. SenatorJosh Hawley (R)202-224-6154 · contact formstatewide
State Senator (State Senate District 18)Cindy O'Laughlin (R)100%
State Representative (State House District 4)Greg Sharpe (R)100%

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 18100%

State house districtShare of ZIP residents
State House District 4100%

Voting precincts

4 voting precincts overlap ZIP 63473. 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:

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ZIP 63473 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.