Postal reference / United States

01821Billerica, Massachusetts

ZIP code 01821 is a United States postal code for Billerica, Massachusetts. Its county association is Middlesex County. The map reference point is at 42.5519, -71.2518.

State / territory
Massachusetts
Recorded place name
Billerica
County association
Middlesex
Estimated coordinate
42.5519, -71.2518
View on OpenStreetMap
ZIP prefix
018 · 47 ZIP codes share it
Data source
GeoNames postal reference, snapshot September 26, 2026

GeoNames reference data. County associations may not include every intersecting county, place names are postal names rather than legal boundaries, and coordinates are approximate. This is not address validation.

Area

Land area
16.592 sq mi (2023 Census Gazetteer)

Figures are for the ZIP Code Tabulation Area (ZCTA) that most closely matches this ZIP code, not an exact match to USPS delivery boundaries. Source: U.S. Census Bureau, 2023 Gazetteer + 2023 ACS 5-Year Estimates, retrieved 2026-09-27. How to read this data.

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Other ZIP codes in Billerica, MA

Billerica has 2 ZIP codes in the reference dataset.

Nearby ZIP code reference points

ZIP codePlaceStateCounty associationMiles
01822BillericaMAMiddlesex1.0
01865Nutting LakeMAMiddlesex1.3
01866PinehurstMAMiddlesex2.0
01862North BillericaMAMiddlesex2.6
01876TewksburyMAMiddlesex3.8
01803BurlingtonMAMiddlesex4.0
01887WilmingtonMAMiddlesex4.1
01805BurlingtonMAMiddlesex4.3

Straight-line distance between reference points. Nearby points do not prove that ZIP areas touch.

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