Dorchester, MA — rate center
- State
- Massachusetts
- Active prefixes
- 35
- Carriers
- 14
- Pooled prefixes
- 25
- LATA
- 128
- Metro area
- Boston-Cambridge-Newton, MA-NH MSA
In NANP numbering, Dorchester, Massachusetts is a rate center — the anchor point for local numbers. It is reached through 617, 857 (multiple area codes serve it).
The rate center currently carries 35 working prefixes, held by 14 different carriers. Pooling applies to 25 of them — individual thousands-blocks may belong to different companies.
The rate center belongs to the Boston-Cambridge-Newton, MA-NH Metropolitan Statistical Area. Routing-wise it sits in LATA 128.
Because 617, 857 all serve this territory, two Dorchester numbers can look completely different while being neighbors — check the prefix, not just the area code.
A Dorchester prefix on caller ID is a starting point, not proof of origin — numbers travel with their owners and displays can be spoofed. Use official callback numbers for anything sensitive.
Prefixes anchored to Dorchester
| Prefix | Code holder | Pooled |
|---|---|---|
| 617-265 | VERIZON NEW ENGLAND INC. | No |
| 617-282 | VERIZON NEW ENGLAND INC. | No |
| 617-287 | VERIZON NEW ENGLAND INC. | No |
| 617-288 | VERIZON NEW ENGLAND INC. | No |
| 617-297 | LEVEL 3 COMMUNICATIONS, LLC - MA | Yes |
| 617-326 | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | Yes |
| 617-379 | RCN TELECOM SERVICES, INC. - MA | Yes |
| 617-436 | VERIZON NEW ENGLAND INC. | No |
| 617-446 | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | Yes |
| 617-474 | VERIZON NEW ENGLAND INC. | Yes |
| 617-506 | PAETEC ITEL, LLC | Yes |
| 617-514 | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | Yes |
| 617-533 | VERIZON NEW ENGLAND INC. | Yes |
| 617-704 | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | Yes |
| 617-707 | NORFOLK COUNTY INTERNET, INC. | No |
| 617-740 | VERIZON NEW ENGLAND INC. | Yes |
| 617-781 | COMMIO, LLC | Yes |
| 617-822 | VERIZON NEW ENGLAND INC. | No |
| 617-825 | VERIZON NEW ENGLAND INC. | No |
| 617-905 | METROPCS, INC. | Yes |
| 617-929 | VERIZON NEW ENGLAND INC. | No |
| 617-979 | PAETEC ITEL, LLC | No |
FAQ
What area code is Dorchester, MA?
Dorchester is served by 2 area codes — 617, 857 — which overlay the same territory.
How many prefixes does Dorchester have?
35 active NXX prefixes are anchored to this rate center in NANPA records, held by 14 carriers.
Is a call from a Dorchester prefix really from Dorchester?
Not necessarily. The prefix marks where the number block was issued; porting, VoIP and spoofing all detach calls from that geography.