ZIP code 21704 is in Urbana (67% of residents), Bartonsville (14%) and Ballenger Creek (5.4%), in Frederick County, Maryland. 13% of its residents live outside city limits. It is in Maryland's 6th congressional district. Its state senate districts are State Senate District 3 (51%) and State Senate District 4 (49%); its state house districts are State Legislative District 3 (51%) and State Legislative District 4 (49%).
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).
8 voting precincts overlap ZIP 21704.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:21704")
ZIP 21704 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.