ZIP code 21042 is in Ellicott City (82% of residents), in Howard County, Maryland. 18% of its residents live outside city limits. It is in Maryland's 3rd congressional district. Its state senate districts are State Senate District 9 (97%) and State Senate District 12 (3.0%); its state house districts are State Legislative Subdistrict 9A (60%), State Legislative Subdistrict 9B (37%) and State Legislative Subdistrict 12A (3.0%).
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).
14 voting precincts overlap ZIP 21042.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:21042")
ZIP 21042 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.