| District of Massachusetts area codes: 857 | |
|---|---|
| Country | United States |
| State/Province | Massachusetts |
| Major City | Boston |
| Time Zone | Eastern |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 857-200 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-201 | Suffolk | Winthrop, MA | Sprint Spectrum L.p. |
| 857-202 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-203 | Suffolk | Jamaica Plain, MA | Verizon New England Inc. |
| 857-204 | Suffolk | Boston, MA | Omnipoint Miami E License |
| 857-205 | Suffolk | Boston, MA | New Cingular Wireless PCS - DC |
| 857-206 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-207 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-208 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-209 | Middlesex | Cambridge, MA | Broadwing Communications |
| 857-210 | Suffolk | Boston, MA | Sprint Spectrum L.p. |
| 857-212 | Suffolk | Boston, MA | Sprint Spectrum L.p. |
| 857-213 | Suffolk | Boston, MA | Paetec Communications |
| 857-214 | Suffolk | Boston, MA | Cellco Partnership DBA Verizon Wireless |
| 857-215 | Norfolk | Brookline, MA | Verizon New England Inc. |
| 857-216 | Middlesex | Cambridge, MA | Ymax Communications Corp. |
| 857-217 | Suffolk | Dorchester, MA | Sprint Spectrum L.p. |
| 857-218 | Norfolk | Brookline, MA | Verizon New England Inc. |
| 857-219 | Suffolk | Boston, MA | Neutral Tandem-massachusetts |
| 857-220 | Suffolk | Dorchester, MA | Broadview Networks |
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.