Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 657 [Rate centres in NPA 657] [Dial plan for NPA 657]

NXX: 441

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-441 A Westminster CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730      
657-441 0 Westminster CA   649C ONVOY, LLC - CA 730   2018-01-06   
657-441 1 Westminster CA   649C ONVOY, LLC - CA 730   2018-01-06   
657-441 2 Westminster CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2018-09-01   
657-441 3 Westminster CA   7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730   2018-09-04   
657-441 4 Westminster CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2018-09-01   
657-441 5 Westminster CA   707H INTEGRATED PATH COMMUNICATIONS, LLC - CA 730   2018-05-08   
657-441 6 Westminster CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2018-09-11   
657-441 7 Westminster CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2018-09-11   
657-441 8 Westminster CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2018-10-01   
657-441 9 Westminster CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2018-10-01   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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