Find the last 4 digits (ZIP+4) for an address in 20851

ZIP 20851, Rockville, MD is filled in. Just type the street address.

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ZIP Code 20851 – Rockville, MD

Rockville, Maryland · Montgomery County · Eastern time

ZIP code20851
CityRockville
StateMaryland
CountyMontgomery County
Population14,946
Time zoneEastern · local time
ZIP typeStandard (has a Census ZCTA area)
Land area2.54 sq mi
Center (lat, long)39.0781, -77.1208

Area codes in this area

227240301

These are the area codes that most often serve ZIP 20851 (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

20847 Rockville · 1.8 mi20849 Rockville · 1.8 mi20857 Rockville · 1.8 mi20852 Rockville · 1.8 mi20883 Gaithersburg · 2.1 mi20853 Rockville · 2.2 mi20896 Garrett Park · 3.3 mi20850 Rockville · 3.3 mi

About ZIP 20851

ZIP code 20851 is assigned to Rockville, Maryland. It lies in Montgomery County. Its Census area covers about 2.54 square miles of land. The closest neighboring ZIP is 20847 (Rockville), about 1.8 miles away.

Every address in 20851 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