Boundary Atlas

ZIP code 06830: Greenwich, CT

ZIP code 06830 is in Greenwich (53% of residents), Byram (18%), Cos Cob (3.0%) and Indian Field (2.8%), in Western Connecticut Planning Region, Connecticut. 23% of its residents live outside city limits. It is in Connecticut's 4th congressional district. Its state senate district is State Senate District 36; its state house districts are State House District 150 (61%), State House District 151 (36%) and State House District 149 (3.5%).

25,043residents (2020 Census)
13.5 sq miland area
4cities and towns
1congressional district
11voting precincts

See it on the mapAll of Connecticut

City and county

City or townShare of ZIP residents
Greenwich53%
Byram18%
Cos Cob3.0%
Indian Field2.8%

CountyShare of ZIP residents
Western Connecticut Planning Region100%

Town or county subdivisionShare of ZIP residents
Greenwich town100%

Congressional district

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

State legislative districts

State senate districtShare of ZIP residents
State Senate District 36100%

State house districtShare of ZIP residents
State House District 15061%
State House District 15136%
State House District 1493.5%

Voting precincts

11 voting precincts overlap ZIP 06830. 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:06830")

ZIP 06830 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.