CAMBRIDGE prefixes in area code 857
NANPA records 28 assigned NXX blocks to rate center CAMBRIDGE in area code 857, 7.8% of the 361 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 17 holders hold those blocks, the largest being CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA (5), OMNIPOINT MIAMI E LICENSE, LLC (3), ONVOY, LLC - MA (3). The earliest assignment on record here is 2001-04-23 and the most recent 2026-05-04. 27 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots. The same rate center name also appears in area codes 208, 308, 309, 410 – overlay codes cover the same geography, so a rate center is served by all of them.
Prefixes assigned here
| Prefix | Holder of record | Assigned | Pooled | In service |
|---|---|---|---|---|
| 857-209 | Lumen LEVEL 3 COMMUNICATIONS, LLC - MA | 2001-10-11 | yes | yes |
| 857-235 | Verizon VERIZON NEW ENGLAND INC. | 2008-11-18 | yes | yes |
| 857-242 | TPx U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | 2011-09-08 | yes | yes |
| 857-253 | Windstream PAETEC ITEL, LLC | 2001-04-23 | yes | yes |
| 857-259 | AT&T NEW CINGULAR WIRELESS PCS, LLC - DC | 2011-05-24 | yes | yes |
| 857-270 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | 2014-09-30 | yes | yes |
| 857-285 | Windstream PAETEC ITEL, LLC | 2012-08-16 | yes | yes |
| 857-298 | Charter ONVOY SPECTRUM, LLC | 2017-09-22 | yes | yes |
| 857-320 | T-Mobile OMNIPOINT MIAMI E LICENSE, LLC | 2014-10-14 | yes | yes |
| 857-331 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | 2015-07-22 | yes | yes |
| 857-357 | MEGAPHONE, INC. | 2019-12-24 | yes | yes |
| 857-412 | Onvoy ONVOY, LLC - MA | – | yes | yes |
| 857-420 | Onvoy ONVOY, LLC - MA | 2022-11-23 | yes | yes |
| 857-434 | SHELCOMM | 2026-05-04 | no | yes |
| 857-500 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | 2011-04-17 | yes | yes |
| 857-529 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | 2015-02-03 | yes | yes |
| 857-600 | Bandwidth BANDWIDTH.COM CLEC, LLC - MA | 2011-04-06 | yes | yes |
| 857-639 | TON80 COMMUNICATIONS, LLC | 2022-02-15 | yes | yes |
| 857-706 | Lumen LEVEL 3 COMMUNICATIONS, LLC - MA | – | yes | yes |
| 857-756 | METROPOLITAN TELECOMMUNICATIONS OF MASS DBA METTEL | 2005-07-26 | yes | yes |
| 857-757 | THE VOICE APPLICATION NETWORK, LLC | 2015-03-09 | yes | yes |
| 857-777 | Peerless PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA | 2012-03-05 | yes | yes |
| 857-799 | HD CARRIER LLC | 2018-11-06 | yes | yes |
| 857-829 | T-Mobile OMNIPOINT MIAMI E LICENSE, LLC | 2002-08-13 | yes | yes |
| 857-856 | Onvoy ONVOY, LLC - MA | 2015-03-18 | yes | yes |
| 857-928 | T-Mobile OMNIPOINT MIAMI E LICENSE, LLC | 2001-08-03 | yes | yes |
| 857-998 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | 2001-05-03 | yes | yes |
| 857-999 | Peerless PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA | 2012-05-23 | yes | yes |
The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.
Who holds the blocks
| Holder | Brand | Blocks | Share here |
|---|---|---|---|
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA | Verizon | 5 | 17.9% |
| OMNIPOINT MIAMI E LICENSE, LLC | T-Mobile | 3 | 10.7% |
| ONVOY, LLC - MA | Onvoy | 3 | 10.7% |
| LEVEL 3 COMMUNICATIONS, LLC - MA | Lumen | 2 | 7.1% |
| PAETEC ITEL, LLC | Windstream | 2 | 7.1% |
| PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA | Peerless | 2 | 7.1% |
| VERIZON NEW ENGLAND INC. | Verizon | 1 | 3.6% |
| U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS | TPx | 1 | 3.6% |
| NEW CINGULAR WIRELESS PCS, LLC - DC | AT&T | 1 | 3.6% |
| ONVOY SPECTRUM, LLC | Charter | 1 | 3.6% |
| MEGAPHONE, INC. | – | 1 | 3.6% |
| SHELCOMM | – | 1 | 3.6% |
| BANDWIDTH.COM CLEC, LLC - MA | Bandwidth | 1 | 3.6% |
| TON80 COMMUNICATIONS, LLC | – | 1 | 3.6% |
| METROPOLITAN TELECOMMUNICATIONS OF MASS DBA METTEL | – | 1 | 3.6% |
| THE VOICE APPLICATION NETWORK, LLC | – | 1 | 3.6% |
| HD CARRIER LLC | – | 1 | 3.6% |
Same rate center in other codes
Overlay codes cover the same geography, so one rate center is served by all of them.
Frequently asked
Which prefixes belong to CAMBRIDGE in area code 857?
28 blocks: 209, 235, 242, 253, 259, 270, 285, 298, 320, 331, 357, 412 and 16 more, all listed in the table above.
Which carriers have numbers in CAMBRIDGE?
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA (5 blocks), OMNIPOINT MIAMI E LICENSE, LLC (3 blocks), ONVOY, LLC - MA (3 blocks), LEVEL 3 COMMUNICATIONS, LLC - MA (2 blocks), PAETEC ITEL, LLC (2 blocks), PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA (2 blocks). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.
Is CAMBRIDGE a city?
It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.