ZIP code 21409 is in Cape St. Claire (43% of residents) and Arnold (9.2%), in Anne Arundel County, Maryland. 47% of its residents live outside city limits. It is in Maryland's 3rd congressional district. Its state senate districts are State Senate District 33 (79%) and State Senate District 30 (21%); its state house districts are State Legislative Subdistrict 33C (79%) and State Legislative Subdistrict 30A (21%).
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).
9 voting precincts overlap ZIP 21409.
Map them, with each precinct's share of the ZIP's residents.
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ZIP 21409 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.