857 Area Code

The 857 area code covers Boston and several surrounding communities in Massachusetts.

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/ 857

Area Code 857 Location: Massachusetts

The 857 area code covers the same geographic area as area code 617, encompassing the city of Boston and several surrounding communities in Massachusetts.

Counties Served by Area Code 857:

  • Essex
  • Middlesex
  • Norfolk
  • Suffolk

Major Cities in the 857 Service Area:

Other Cities and Towns:

  • Belmont
  • Chelsea
  • Everett
  • Milton
  • Somerville
  • Watertown
  • Winthrop

Overlay System

Area code 857 is an overlay of area code 617. Area code 617 was created in October 1947. Area code 857 was overlaid onto 617 on May 2, 2001. Since then, 10-digit local dialing has been mandatory.

Area Code 857 Location Map

Area Code 857 Location on Massachusetts Map

Area code 857 is a general purpose code which was placed in service on May 2, 2001.

857 Area Code Prefixes

Our Massachusetts phone number lookup service will analyze the three-digit prefix of any 857 area code phone number and will show which telecommunications company and rate center it was initially assigned to. This prefix code data may help to determine the U.S. carrier, Massachusetts geographic region, and local calling area associated with the phone number.

Phone numbers follow the following structure under the North American Numbering Plan:

  • NPA- area code (where the number was originally assigned)
  • NXX - Central office code that locates the specific neighborhood and identifies the service provider
  • XXXX - Subscriber number identifies the individual phone line within that local exchange

Understanding the area code can help you determine if a call is local to your area. However, keep in mind that due to mobile number portability and VoIP services, the caller may be anywhere in the United States, so it’s best to search for the most recent phone number details.

Prefixes by Company

Company Number of Prefixes
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 24
OMNIPOINT MIAMI E LICENSE, LLC 20
SPRINT SPECTRUM, L.P. 10
METROPCS, INC. 8
VERIZON NEW ENGLAND INC. 8
NEW CINGULAR WIRELESS PCS, LLC - DC 6
BANDWIDTH.COM CLEC, LLC - MA 5
BROADVIEW NETWORKS, INC. - MA 5
LEVEL 3 COMMUNICATIONS, LLC - MA 4
XO MASSACHUSETS, INC. 4
ONVOY, LLC - MA 3
PAETEC COMMUNICATIONS, INC. - MA 3
COMCAST IP PHONE, LLC 2
CTC COMMUNICATIONS CORP. - MA 2
PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 2
TC SYSTEMS, INC. 2
BARR TELL USA, INC. - MA 1
CENTURYLINK COMMUNICATIONS, LLC 1
COMMIO, LLC 1
DSCI, LLC 1
LOCAL ACCESS LLC - MA 1
METROPOLITAN TELECOMMUNICATIONS OF MASS DBA METTEL 1
MOSAIC NETWORX LLC - MA 1
NUSO, LLC 1
RCLEC, INC. 1
TELENGY LLC 1
VONAGE AMERICA LLC 1
WIDE VOICE, LLC - MA 1

Carrier names have been updated from their original FCC assignments to reflect current companies following mergers, acquisitions, and rebranding. Updates were determined using AI-assisted research and may not be accurate or reflect up to date changes. This data is provided without warranties of accuracy or completeness.

Prefixes by Rate Center

Rate Center Number of Prefixes
BOSTON 72
CAMBRIDGE 12
BROOKLINE 6
BRIGHTON 4
DORCHESTER 4
JAMAICA PL 4
ROXBURY 4
NEWTON 3
CHARLESTN 2
QUINCY 2
WATERTOWN 2
BELMONT 1
CHELSEA 1
HYDE PARK 1
MILTON 1
SO BOSTON 1

Other Massachusetts Area Codes

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