Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 341 [Rate centres in NPA 341] [Dial plan for NPA 341]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
341-257 A Fremont-Newark: Main DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2024-12-01   
341-257 0 Fremont-Newark: Main DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2024-12-01   
341-257 1 Fremont-Newark: Main DA CA   624H ONVOY SPECTRUM, LLC 722   2025-01-30   
341-257 2 Fremont-Newark: Main DA CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2025-07-14   
341-257 3 Fremont-Newark: Main DA CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2025-08-14   
341-257 4 Fremont-Newark: Main DA CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2025-09-10   
341-257 8 Fremont-Newark: Main DA CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2025-03-23   
341-257 9 Fremont-Newark: Main DA CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 722   2025-05-11   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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