ZIP code 20678 is in Prince Frederick (24% of residents), in Calvert County, Maryland. 76% of its residents live outside city limits. It is in Maryland's 5th congressional district. Its state senate district is State Senate District 27; its state house district is State Legislative Subdistrict 27C.
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).
4 voting precincts overlap ZIP 20678.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:20678")
ZIP 20678 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.