857
Area code

MA

United States geographic area code, in service since 2001-05-02. Part of the 617/857 overlay complex — ten-digit dialing required.

Split from 617. Overlaid with 617 .

Statusin service
Introduced2001-05-02
JurisdictionMA, US
Local dialing10D
Time zoneEastern
Last verified2026-09-17
Utilization 48.2% of assignable prefixes assigned As of 09/17/2026
0%382 of ~792 assignable NXX values (200–999 excl. N11)100%

Prefix-level assignment does not equal number-level exhaustion; thousands-block pooling extends capacity. First assignment on record 2001-03-19, most recent 2026-06-30.

Area codes serve rate-center geographies, not municipal boundaries. “MA” identifies the jurisdiction, not an exact city footprint.

Top assignees

Ranked by assigned prefixes · initial assignee ≠ current carrier
Largest initial assignees in area code 857
RankAssigneePrefixesShare
01 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 67 17.5%
02 OMNIPOINT MIAMI E LICENSE, LLC 61 16%
03 ONVOY, LLC - MA 42 11%
04 METROPCS, INC. 25 6.5%
05 PAETEC ITEL, LLC 19 5%
06 NEW CINGULAR WIRELESS PCS, LLC - DC 18 4.7%
07 VERIZON NEW ENGLAND INC. 17 4.5%
08 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 13 3.4%
09 LEVEL 3 COMMUNICATIONS, LLC - MA 10 2.6%
10 BANDWIDTH.COM CLEC, LLC - MA 10 2.6%

Important: these are initial assignees from NANPA CO-code records — the carrier a prefix was originally assigned to. Because of number portability, the current serving carrier of any individual number may differ.

Change history

Recorded events for this NPA
  • 2001-05-02Area code 857 entered service (created from 617).

Planning letters & orders

Primary documents
NANPA planning letters for area code 857
DateDocumentSubject
2000-07-11 PL-234 ↗ NPA 774 To Overlay NPA 508; NPA 857 To Overlay NPA 617; NPA 339 To Overlay NPA 781; and NPA 351 To Overlay NPA 978 (Massachusetts)

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