Boundary Atlas

ZIP code 01129: Springfield, MA

ZIP code 01129 is in Springfield, in Hampden County, Massachusetts. It is in Massachusetts's 1st congressional district. Its state senate districts are Hampden District (85%) and Hampden-Hampshire-Worcester District (15%); its state house districts are 12th Hampden District (98%) and 9th Hampden District (1.9%).

7,024residents (2020 Census)
3.4 sq miland area
1cities and towns
1congressional district
7voting precincts

See it on the mapAll of Massachusetts

City and county

City or townShare of ZIP residents
Springfield100%

CountyShare of ZIP residents
Hampden County100%

Town or county subdivisionShare of ZIP residents
Springfield city100%

Congressional district

Congressional districtShare of ZIP residents
Massachusetts's 1st congressional district (MA-01)100%

State legislative districts

State senate districtShare of ZIP residents
Hampden District85%
Hampden-Hampshire-Worcester District15%

State house districtShare of ZIP residents
12th Hampden District98%
9th Hampden District1.9%

Voting precincts

7 voting precincts overlap ZIP 01129. 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:01129")

ZIP 01129 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.