Boundary Atlas

ZIP code 11951: Mastic Beach, NY

ZIP code 11951 is in Mastic Beach (99% of residents) and Shirley (1.0%), in Suffolk County, New York. It is in New York's 2nd congressional district. Its state senate district is State Senate District 3; its state house district is Assembly District 3.

13,827residents (2020 Census)
4.8 sq miland area
2cities and towns
1congressional district
11voting precincts

See it on the mapAll of New York

City and county

City or townShare of ZIP residents
Mastic Beach99%
Shirley1.0%

CountyShare of ZIP residents
Suffolk County100%

Town or county subdivisionShare of ZIP residents
Brookhaven town100%

Congressional district

Congressional districtShare of ZIP residents
New York's 2nd congressional district (NY-02)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (NY-02)Andrew R. Garbarino (R)202-225-7896100%
U.S. SenatorCharles E. Schumer (D)202-224-6542 · contact formstatewide
U.S. SenatorKirsten E. Gillibrand (D)202-224-4451 · contact formstatewide
State Senator (State Senate District 3)Dean Murray (Republican/Conservative)631-360-3356100%
Assembly Member (Assembly District 3)Joe DeStefano (Republican/Conservative)631-207-0073100%

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 3100%

State house districtShare of ZIP residents
Assembly District 3100%

Voting precincts

11 voting precincts overlap ZIP 11951. 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:

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ZIP 11951 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.