Boundary Atlas

ZIP code 02558: Onset, MA

ZIP code 02558 is in Onset (68% of residents), in Plymouth County, Massachusetts. 32% of its residents live outside city limits. It is in Massachusetts's 9th congressional district. Its state senate district is Third Bristol and Plymouth District; its state house district is 2nd Plymouth District.

2,178residents (2020 Census)
1.1 sq miland area
1cities and towns
1congressional district
2voting precincts

See it on the mapAll of Massachusetts

City and county

City or townShare of ZIP residents
Onset68%

CountyShare of ZIP residents
Plymouth County100%

Town or county subdivisionShare of ZIP residents
Wareham town100%

Congressional district

Congressional districtShare of ZIP residents
Massachusetts's 9th congressional district (MA-09)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (MA-09)William R. Keating (D)202-225-3111100%
U.S. SenatorEdward J. Markey (D)202-224-2742 · contact formstatewide
U.S. SenatorElizabeth Warren (D)202-224-4543 · contact formstatewide
State Senator (Third Bristol and Plymouth District)Kelly Dooner (R)100%
State Representative (2nd Plymouth District)John Gaskey (R)100%

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
Third Bristol and Plymouth District100%

State house districtShare of ZIP residents
2nd Plymouth District100%

Voting precincts

2 voting precincts overlap ZIP 02558. Map them, with each precinct's share of the ZIP's residents.

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ZIP 02558 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.