| District of Massachusetts area codes: 857 | |
|---|---|
| Country | United States |
| State/Province | Massachusetts |
| Major City | Boston |
| Time Zone | Eastern |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 857-377 | Suffolk | Boston, MA | Paetec Communications |
| 857-383 | Suffolk | Boston, MA | Teleport Communications America |
| 857-389 | Suffolk | Charlestown, MA | Omnipoint Miami E License |
| 857-399 | Suffolk | Roxbury, MA | Bandwidth.com Clec |
| 857-400 | Suffolk | Boston, MA | Bandwidth.com Clec |
| 857-401 | Suffolk | S Boston, MA | Broadview Networks |
| 857-403 | Norfolk | Quincy, MA | Paetec Communications |
| 857-404 | Middlesex | Newton, MA | Comcast Phone Of Massachusetts |
| 857-413 | Suffolk | Boston, MA | Broadwing Communications |
| 857-415 | Suffolk | Boston, MA | Vonage Network Inc. |
| 857-417 | Suffolk | Boston, MA | Metro PCS |
| 857-444 | Suffolk | Boston, MA | Peerless Network Of Massachusetts |
| 857-445 | Suffolk | Boston, MA | New Cingular Wireless PCS - DC |
| 857-449 | Suffolk | Boston, MA | Comcast Phone Of Massachusetts |
| 857-452 | Suffolk | Charlestown, MA | Sprint Spectrum L.p. |
| 857-453 | Suffolk | Boston, MA | Broadwing Communications |
| 857-472 | Suffolk | Boston, MA | New Cingular Wireless PCS - DC |
| 857-488 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-492 | Suffolk | Roxbury, MA | Sprint Spectrum L.p. |
| 857-496 | Suffolk | S Boston, MA | Comcast Phone Of Massachusetts |
There are 164 prefixes, In the code area, the major cities are Belmont, MA;Boston, MA;Brookline, MA;Cambridge, MA. The major city is Boston.