ZIP code 20855 is in Redland (66% of residents), Derwood (15%) and Rockville (3.9%), in Montgomery County, Maryland. 16% of its residents live outside city limits. It is in Maryland's 8th congressional district. Its state senate district is State Senate District 19; its state house district is State Legislative District 19.
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 20855.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:20855")
ZIP 20855 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.