ZIP code 21045 is in Columbia (99% of residents) and Ellicott City (1.0%), in Howard County, Maryland. It is in Maryland's 3rd congressional district. Its state senate districts are State Senate District 13 (82%) and State Senate District 12 (18%); its state house districts are State Legislative District 13 (82%) and State Legislative Subdistrict 12A (18%).
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).
10 voting precincts overlap ZIP 21045.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:21045")
ZIP 21045 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.