Find the last 4 digits (ZIP+4) for an address in 01821

ZIP 01821, Billerica, MA is filled in. Just type the street address.

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ZIP Code 01821 – Billerica, MA

Billerica, Massachusetts · Middlesex County · Eastern time

ZIP code01821
CityBillerica
StateMassachusetts
CountyMiddlesex County
Population30,143
Time zoneEastern · local time
ZIP typeStandard (has a Census ZCTA area)
Land area16.59 sq mi
Center (lat, long)42.5493, -71.2517

Area codes in this area

781339

These are the area codes that most often serve ZIP 01821 (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

01822 Billerica · 1.1 mi01865 Nutting Lake · 1.2 mi01866 Pinehurst · 1.8 mi01862 North Billerica · 3 mi01730 Bedford · 3.8 mi01803 Burlington · 4.1 mi01805 Burlington · 4.2 mi01876 Tewksbury · 4.5 mi

About ZIP 01821

ZIP code 01821 is assigned to Billerica, Massachusetts. It lies in Middlesex County. Its Census area covers about 16.59 square miles of land. The closest neighboring ZIP is 01822 (Billerica), about 1.1 miles away.

Every address in 01821 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