Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 442 [Rate centres in NPA 442] [Dial plan for NPA 442]

NXX: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
442-423 A Lake Isabella CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730      
442-423 0 Lake Isabella CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2020-12-12   
442-423 1 Lake Isabella CA   649C ONVOY, LLC - CA 730   2021-08-09   
442-423 3 Lake Isabella CA   857F MCC TELEPHONY OF THE WEST, LLC - CA 730   2021-01-11   
442-423 5 Lake Isabella CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2023-03-23   
442-423 7 Lake Isabella CA   939H COMMIO, LLC 730   2022-10-16   
442-423 8 Lake Isabella CA   6529 T-MOBILE USA, INC. 730   2022-04-17   
442-423 9 Lake Isabella CA   6529 T-MOBILE USA, INC. 730   2021-03-06   

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

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