Boundary Atlas

ZIP code 06870: Old Greenwich, CT

ZIP code 06870 is in Old Greenwich (89% of residents) and Riverside (5.8%), in Western Connecticut Planning Region, Connecticut. 5.0% 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 (60%) and State House District 151 (40%).

7,720residents (2020 Census)
2.3 sq miland area
2cities and towns
1congressional district
5voting precincts

See it on the mapAll of Connecticut

City and county

City or townShare of ZIP residents
Old Greenwich89%
Riverside5.8%

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%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (CT-04)James A. Himes (D)202-225-5541100%
U.S. SenatorChristopher Murphy (D)202-224-4041 · contact formstatewide
U.S. SenatorRichard Blumenthal (D)202-224-2823 · contact formstatewide
State Senator (State Senate District 36)Ryan Fazio (R)100%
State Representative (State House District 150)Steve Meskers (Democratic)60%
State Representative (State House District 151)Héctor Arzeno (Democratic)40%

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 36100%

State house districtShare of ZIP residents
State House District 15060%
State House District 15140%

Voting precincts

5 voting precincts overlap ZIP 06870. Map them, with each precinct's share of the ZIP's residents.

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ZIP 06870 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.