351 Area Code

Area Code Overview

Area code 351 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 1,134,428.

Overlay and Dialing Rules

  • Area Code: 351
  • State: Massachusetts
  • Type: General Purpose Code
  • In Service Date: May 2, 2001
  • Overlay Complex: 351/978
  • 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 351

This area code is ranked 337th out of 363 nationwide in estimated assigned phone numbers. Within the state territory it serves, it is ranked 9th out of 9.

722,000

Estimated Service-Type Mix of Assigned Phone Numbers in Area Code 351

Total assigned 722,000
Wireless
183,000 assigned
25.35%
Wireline and VoIP
481,000 assigned
66.62%
Other / Unclassified
58,000 assigned
8.03%

Estimated Share of Wireless Numbers Originally Assigned to Each Carrier in Area Code 351

Estimated assigned wireless phone numbers: 183,000

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

T-Mobile 97,000 (53.01%)
Verizon Wireless 45,000 (24.59%)
AT&T Wireless 31,000 (16.94%)
MASS MOBILE LLC 10,000 (5.46%)

Estimated Share of Wireline and VoIP Numbers Originally Assigned to Each Carrier in Area Code 351

Estimated assigned wireline and VoIP phone numbers: 481,000

Onvoy 285,000 (59.25%)
Spectrum 74,000 (15.38%)
Peerless Network 37,000 (7.69%)
Commio 27,000 (5.61%)
Bandwidth 18,000 (3.74%)
Comcast Business 15,000 (3.12%)
Telnyx 14,000 (2.91%)
TERRA NOVA TELECOM INC. 4,000 (0.83%)
Vonage 3,000 (0.62%)
AT&T 1,000 (0.21%)
Lumen 1,000 (0.21%)
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 1,000 (0.21%)

Other / Unclassified Assigned Numbering in Area Code 351

Estimated assigned other or unclassified phone numbers: 58,000

FRACTEL, LLC 18,000 (31.03%)
HD CARRIER LLC 15,000 (25.86%)
TON80 COMMUNICATIONS, LLC 10,000 (17.24%)
IP HORIZON LLC 7,000 (12.07%)
TC SYSTEMS, INC. 3,000 (5.17%)
IDT AMERICA, CORP. - MA 2,000 (3.45%)
BARR TELL USA, INC. - MA 1,000 (1.72%)
EXIANT COMMUNICATIONS LLC 1,000 (1.72%)
FIVE9, INC. 1,000 (1.72%)

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 351, 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