ZIP code 21001 is in Aberdeen (61% of residents), Perryman (9.2%) and Riverside (5.0%), in Harford County, Maryland. 25% of its residents live outside city limits. It is in Maryland's 1st congressional district. Its state senate districts are State Senate District 34 (91%) and State Senate District 35 (8.8%); its state house districts are State Legislative Subdistrict 34A (91%) and State Legislative Subdistrict 35A (8.8%).
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).
12 voting precincts overlap ZIP 21001.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:21001")
ZIP 21001 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.