ZIP code 15666 is in Mount Pleasant (27% of residents), Calumet (4.2%), Norvelt (3.6%) and Mammoth (3.4%), in Westmoreland County (88%) and Fayette County (12%), Pennsylvania. 62% of its residents live outside city limits. It is in Pennsylvania's 14th congressional district. Its state senate districts are State Senate District 39 (88%) and State Senate District 32 (12%); its state house districts are State House District 58 (68%), State House District 59 (20%) and State House District 52 (12%).
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).
21 voting precincts overlap ZIP 15666.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:15666")
ZIP 15666 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.