ZIP code 03878 is in Somersworth (99% of residents), in Strafford County, New Hampshire. It is in New Hampshire's 1st congressional district. Its state senate district is State Senate District 4; its state house district is State House District Strafford 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).
6 voting precincts overlap ZIP 03878.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:03878")
ZIP 03878 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.