Home

857 Area Code

Area Code Overview

Area code 857 is a geographic telephone area code in Massachusetts that went into service on May 2, 2001. The geographic regions covered by this area code overlay has a population of approximately 2,390,696.

Overlay and Dialing Rules

  • Area Code: 857
  • State: Massachusetts
  • Type: General Purpose Code
  • In Service Date: May 2, 2001
  • Overlay Complex: 617/857
  • Local Dialing Plan: This area does require you to dial the area code when calling locally.

Estimated Number of Assigned Phone Numbers in Area Code 857

This area code is ranked 247th out of 363 nationwide in estimated assigned phone numbers. Within the state territory it serves, it is ranked 7th out of 9.

3,296,000

Estimated Service-Type Mix of Assigned Phone Numbers in Area Code 857

Total assigned 3,296,000
Wireless
1,526,000 assigned
46.30%
Wireline and VoIP
1,588,000 assigned
48.18%
Other / Unclassified
182,000 assigned
5.52%

Estimated Share of Wireless Numbers Originally Assigned to Each Carrier in Area Code 857

Estimated assigned wireless phone numbers: 1,526,000

Numbers may later be ported to another carrier, but this chart reflects original number assignment, not current subscriber share.

T-Mobile 801,000 (52.49%)
Verizon Wireless 531,000 (34.80%)
AT&T Wireless 185,000 (12.12%)
MASS MOBILE LLC 7,000 (0.46%)
EVOLVE CELLULAR, INC. 1,000 (0.07%)
Optimum Mobile 1,000 (0.07%)

Estimated Share of Wireline and VoIP Numbers Originally Assigned to Each Carrier in Area Code 857

Estimated assigned wireline and VoIP phone numbers: 1,588,000

Onvoy 625,000 (39.36%)
Bandwidth 165,000 (10.39%)
Lumen 125,000 (7.87%)
PAETEC ITEL, LLC 109,000 (6.86%)
Spectrum 104,000 (6.55%)
VERIZON NEW ENGLAND INC. 87,000 (5.48%)
Comcast Business 81,000 (5.10%)
Peerless Network 70,000 (4.41%)
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 66,000 (4.16%)
Commio 38,000 (2.39%)
Telnyx 27,000 (1.70%)
PAETEC COMMUNICATIONS, INC. - MA 20,000 (1.26%)

Other / Unclassified Assigned Numbering in Area Code 857

Estimated assigned other or unclassified phone numbers: 182,000

HD CARRIER LLC 86,000 (47.25%)
IP HORIZON LLC 25,000 (13.74%)
TC SYSTEMS, INC. 20,000 (10.99%)
U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 13,000 (7.14%)
BARR TELL USA, INC. - MA 12,000 (6.59%)
TON80 COMMUNICATIONS, LLC 11,000 (6.04%)
FRACTEL, LLC 6,000 (3.30%)
INTRADO COMMUNICATIONS, LLC 6,000 (3.30%)
TELENGY LLC 1,000 (0.55%)
THE VOICE APPLICATION NETWORK, LLC 1,000 (0.55%)
WAVENATION, LLC 1,000 (0.55%)

Cities and Towns in Area Code 857

Belmont, Massachusetts Boston, Massachusetts Brighton, Massachusetts Brookline, Massachusetts Cambridge, Massachusetts Charlestown, Massachusetts Chelsea, Massachusetts Dedham, Massachusetts Dorchester, Massachusetts East Boston, Massachusetts Everett, Massachusetts Hyde Park, Massachusetts Jamaica Plain, Massachusetts Kingston, Massachusetts Malden, Massachusetts Melrose, Massachusetts Milton, Massachusetts Newton, Massachusetts Quincy, Massachusetts Roxbury, Massachusetts Saugus, Massachusetts Somerville, Massachusetts South Boston, Massachusetts Waltham, Massachusetts Watertown, Massachusetts Weymouth, Massachusetts Winthrop, Massachusetts

These geographic regions are also served by area code 617.

How These Figures Were Built

These figures are estimates based on public phone-number assignment records. They are meant to show the likely mix of assigned phone numbers associated with area code 857, not live customer counts.

Some providers may have assigned phone numbers tied to this area code even if they do not actively market or sell service locally. These figures reflect public number-assignment records, not confirmed local service availability.

They also do not reflect number portability at the individual phone-number level, so some numbers may now be used on a different network or by a different provider than the original assignment records suggest.

Population data and locality matching provided by GeoNames.

Last refreshed: April 15, 2026 6:22 pm