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

WESTPORT prefixes in area code 203

NANPA records 16 assigned NXX blocks to rate center WESTPORT in area code 203, 2.0% of the 784 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 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT (7), NEW CINGULAR WIRELESS PCS, LLC - DC (2), MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT (2). 9 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 475, 503, 508, 518 – overlay codes cover the same geography, so a rate center is served by all of them.

16 assigned blocks – 2% of 203
8 holders of record
9 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
203-216 AT&T NEW CINGULAR WIRELESS PCS, LLC - DC – yes yes
203-221 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – no yes
203-222 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – no yes
203-226 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – no yes
203-227 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – no yes
203-291 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – yes yes
203-293 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT – yes yes
203-341 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – no yes
203-349 AT&T TELEPORT COMMUNICATIONS AMERICA, LLC - CT – yes yes
203-429 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT – yes yes
203-451 AT&T NEW CINGULAR WIRELESS PCS, LLC - DC – no yes
203-454 AT&T SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT – no yes
203-557 Altice CABLEVISION LIGHTPATH, INC. - CT – yes yes
203-571 AT&T AT&T - LOCAL – yes yes
203-635 Lumen LEVEL 3 COMMUNICATIONS, LLC - CT – yes yes
203-682 Windstream PAETEC ITEL, LLC – 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
SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT AT&T 7 43.8%
NEW CINGULAR WIRELESS PCS, LLC - DC AT&T 2 12.5%
MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT Verizon 2 12.5%
TELEPORT COMMUNICATIONS AMERICA, LLC - CT AT&T 1 6.2%
CABLEVISION LIGHTPATH, INC. - CT Altice 1 6.2%
AT&T - LOCAL AT&T 1 6.2%
LEVEL 3 COMMUNICATIONS, LLC - CT Lumen 1 6.2%
PAETEC ITEL, LLC Windstream 1 6.2%

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 WESTPORT in area code 203?

16 blocks: 216, 221, 222, 226, 227, 291, 293, 341, 349, 429, 451, 454 and 4 more, all listed in the table above.

Which carriers have numbers in WESTPORT?

SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT (7 blocks), NEW CINGULAR WIRELESS PCS, LLC - DC (2 blocks), MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT (2 blocks), TELEPORT COMMUNICATIONS AMERICA, LLC - CT (1 block), CABLEVISION LIGHTPATH, INC. - CT (1 block), AT&T - LOCAL (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is WESTPORT 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 203

All 784 prefixes in 203