Boundary Atlas

ZIP code 45812: Alger, OH

ZIP code 45812 is in Alger (46% of residents), in Hardin County (99%) and Allen County (0.8%), Ohio. 54% of its residents live outside city limits. It is in Ohio's 4th congressional district. Its state senate districts are State Senate District 1 (99%) and State Senate District 12 (0.8%); its state house districts are State House District 83 (99%) and State House District 78 (0.8%).

1,835residents (2020 Census)
38.8 sq miland area
2cities and towns
1congressional district
6voting precincts

See it on the mapAll of Ohio

City and county

City or townShare of ZIP residents
Alger46%
McGuffey0.3%

CountyShare of ZIP residents
Hardin County99%
Allen County0.8%

Town or county subdivisionShare of ZIP residents
Marion township90%
Lynn township6.0%
McDonald township2.2%
Auglaize township0.8%
Cessna township0.8%
Roundhead township0.3%

Congressional district

Congressional districtShare of ZIP residents
Ohio's 4th congressional district (OH-04)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (OH-04)Jim Jordan (R)202-225-2676100%
U.S. SenatorBernie Moreno (R)202-224-2315statewide
U.S. SenatorJon Husted (R)202-224-3353statewide
State Senator (State Senate District 1)Rob McColley (R)99%
State Senator (State Senate District 12)Susan Manchester (R)419-820-81510.8%
State Representative (State House District 83)Ty Mathews (R)99%
State Representative (State House District 78)Matt Huffman (R)0.8%

Elected in 2024 under OH's previous congressional map; this district's lines changed for the 120th Congress (seated January 3, 2027).

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 199%
State Senate District 120.8%

State house districtShare of ZIP residents
State House District 8399%
State House District 780.8%

Voting precincts

6 voting precincts overlap ZIP 45812. Map them, with each precinct's share of the ZIP's residents.

Get this in your AI agent

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:45812")

ZIP 45812 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.