NumberingData
Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

DORCHESTER prefixes in area code 857

NANPA records 13 assigned NXX blocks to rate center DORCHESTER in area code 857, 3.6% 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. 8 holders hold those blocks, the largest being ONVOY, LLC - MA (5), METROPCS, INC. (2), PAETEC ITEL, LLC (1). The earliest assignment on record here is 2001-03-20 and the most recent 2022-11-17. 13 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 402, 430, 531, 534 – overlay codes cover the same geography, so a rate center is served by all of them.

13 assigned blocks – 3.6% of 857
8 holders of record
13 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
857-212 T-Mobile METROPCS, INC. 2001-04-23 yes yes
857-217 T-Mobile METROPCS, INC. 2001-06-29 yes yes
857-220 Windstream PAETEC ITEL, LLC 2001-03-20 yes yes
857-271 Onvoy ONVOY, LLC - MA – yes yes
857-309 Onvoy ONVOY, LLC - MA 2014-12-16 yes yes
857-375 Onvoy ONVOY, LLC - MA 2021-06-14 yes yes
857-385 AT&T NEW CINGULAR WIRELESS PCS, LLC - DC 2016-06-01 yes yes
857-418 TPx U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 2022-11-17 yes yes
857-567 Onvoy ONVOY, LLC - MA 2020-05-15 yes yes
857-587 HD CARRIER LLC – yes yes
857-663 Onvoy ONVOY, LLC - MA – yes yes
857-688 FRACTEL, LLC 2021-10-26 yes yes
857-847 Charter ONVOY SPECTRUM, LLC 2021-03-17 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

HolderBrandBlocksShare here
ONVOY, LLC - MA Onvoy 5 38.5%
METROPCS, INC. T-Mobile 2 15.4%
PAETEC ITEL, LLC Windstream 1 7.7%
NEW CINGULAR WIRELESS PCS, LLC - DC AT&T 1 7.7%
U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS TPx 1 7.7%
HD CARRIER LLC – 1 7.7%
FRACTEL, LLC – 1 7.7%
ONVOY SPECTRUM, LLC Charter 1 7.7%

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 DORCHESTER in area code 857?

13 blocks: 212, 217, 220, 271, 309, 375, 385, 418, 567, 587, 663, 688 and 1 more, all listed in the table above.

Which carriers have numbers in DORCHESTER?

ONVOY, LLC - MA (5 blocks), METROPCS, INC. (2 blocks), PAETEC ITEL, LLC (1 block), NEW CINGULAR WIRELESS PCS, LLC - DC (1 block), U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS (1 block), HD CARRIER LLC (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is DORCHESTER 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.

Other rate centers in 857

All 361 prefixes in 857