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

NORWALK prefixes in area code 475

NANPA records 22 assigned NXX blocks to rate center NORWALK in area code 475, 7.5% of the 292 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. 10 holders hold those blocks, the largest being CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT (10), OMNIPOINT COMMUNICATIONS, INC. - CT (3), LEVEL 3 COMMUNICATIONS, LLC - CT (2). The earliest assignment on record here is 2014-10-03 and the most recent 2025-10-14. 22 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 203, 419, 562, 567 – overlay codes cover the same geography, so a rate center is served by all of them.

22 assigned blocks – 7.5% of 475
10 holders of record
22 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
475-208 Lumen LEVEL 3 COMMUNICATIONS, LLC - CT 2014-12-08 yes yes
475-245 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2016-02-08 yes yes
475-250 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2018-07-23 yes yes
475-257 CSC WIRELESS, LLC 2019-03-28 yes yes
475-258 T-Mobile OMNIPOINT COMMUNICATIONS, INC. - CT 2019-09-12 yes yes
475-266 AT&T NEW CINGULAR WIRELESS PCS, LLC - DC 2015-06-10 yes yes
475-283 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2016-01-05 yes yes
475-288 Lumen LEVEL 3 COMMUNICATIONS, LLC - CT 2014-10-03 yes yes
475-291 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2021-09-27 yes yes
475-322 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2016-04-25 yes yes
475-393 T-Mobile OMNIPOINT COMMUNICATIONS, INC. - CT 2017-07-12 yes yes
475-395 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2015-09-17 yes yes
475-397 Altice CABLEVISION LIGHTPATH, INC. - CT 2025-10-14 yes yes
475-459 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2018-04-20 yes yes
475-470 Onvoy ONVOY, LLC - CT 2016-02-11 yes yes
475-489 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2015-11-17 yes yes
475-544 T-Mobile OMNIPOINT COMMUNICATIONS, INC. - CT 2022-01-14 yes yes
475-673 TON80 COMMUNICATIONS, LLC 2022-01-10 yes yes
475-747 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2015-06-04 yes yes
475-755 FRACTEL, LLC 2020-07-22 yes yes
475-850 BARR TEL USA, INC. - CT 2022-03-02 yes yes
475-889 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 2018-02-09 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
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT Verizon 10 45.5%
OMNIPOINT COMMUNICATIONS, INC. - CT T-Mobile 3 13.6%
LEVEL 3 COMMUNICATIONS, LLC - CT Lumen 2 9.1%
CSC WIRELESS, LLC – 1 4.5%
NEW CINGULAR WIRELESS PCS, LLC - DC AT&T 1 4.5%
CABLEVISION LIGHTPATH, INC. - CT Altice 1 4.5%
ONVOY, LLC - CT Onvoy 1 4.5%
TON80 COMMUNICATIONS, LLC – 1 4.5%
FRACTEL, LLC – 1 4.5%
BARR TEL USA, INC. - CT – 1 4.5%

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 NORWALK in area code 475?

22 blocks: 208, 245, 250, 257, 258, 266, 283, 288, 291, 322, 393, 395 and 10 more, all listed in the table above.

Which carriers have numbers in NORWALK?

CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT (10 blocks), OMNIPOINT COMMUNICATIONS, INC. - CT (3 blocks), LEVEL 3 COMMUNICATIONS, LLC - CT (2 blocks), CSC WIRELESS, LLC (1 block), NEW CINGULAR WIRELESS PCS, LLC - DC (1 block), CABLEVISION LIGHTPATH, INC. - CT (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is NORWALK 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 475

All 292 prefixes in 475