Boundary Atlas

ZIP code 45503: Springfield, OH

ZIP code 45503 is in Springfield (68% of residents) and Northridge (20%), in Clark County, Ohio. 12% of its residents live outside city limits. It is in Ohio's 4th congressional district. Its state senate district is State Senate District 10; its state house district is State House District 74.

32,870residents (2020 Census)
17.5 sq miland area
2cities and towns
1congressional district
24voting precincts

See it on the mapAll of Ohio

City and county

City or townShare of ZIP residents
Springfield68%
Northridge20%

CountyShare of ZIP residents
Clark County100%

Town or county subdivisionShare of ZIP residents
Springfield city68%
Moorefield township27%
Springfield township5.0%

Congressional district

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

State legislative districts

State senate districtShare of ZIP residents
State Senate District 10100%

State house districtShare of ZIP residents
State House District 74100%

Voting precincts

24 voting precincts overlap ZIP 45503. 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:45503")

ZIP 45503 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.