Find the last 4 digits (ZIP+4) for an address in 21758

ZIP 21758, Knoxville, MD is filled in. Just type the street address.

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ZIP Code 21758 – Knoxville, MD

Knoxville, Maryland · Frederick County · Eastern time

ZIP code21758
CityKnoxville
StateMaryland
CountyFrederick CountyWashington County
Population4,409
Time zoneEastern · local time
ZIP typeStandard (has a Census ZCTA area)
Land area32.02 sq mi
Center (lat, long)39.3532, -77.6568

Area codes in this area

227240301

These are the area codes that most often serve ZIP 21758 (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.

Map

Nearby ZIP codes

21715 Brownsville · 1.8 mi21716 Brunswick · 2.9 mi21718 Burkittsville · 3.2 mi21755 Jefferson · 4.8 mi21779 Rohrersville · 4.9 mi20180 Lovettsville · 5.9 mi25425 Harpers Ferry · 7 mi21756 Keedysville · 7.6 mi

About ZIP 21758

ZIP code 21758 is assigned to Knoxville, Maryland. It crosses 2 counties; most of its land is in Frederick County. Its Census area covers about 32.02 square miles of land. The closest neighboring ZIP is 21715 (Brownsville), about 1.8 miles away.

Every address in 21758 also has a 4-digit add-on code (ZIP+4) that points to a smaller delivery area. Use the box above to find it.

Sources: US Census Bureau (ZCTA, county relationship files), GeoNames (CC BY 4.0), NANPA via NumberResearch.org (CC BY 4.0). Map © OpenStreetMap contributors. ZIP areas are approximate. Population: U.S. Census Bureau, ACS 5-year estimates, 2024 (ZCTA). Data sources