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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
442-421 A Lake Isabella CA VTVLCAXAX0Y  624H ONVOY SPECTRUM, LLC 730      
442-421 4 Lake Isabella CA   624H ONVOY SPECTRUM, LLC 730   2023-06-15   
442-421 5 Lake Isabella CA   624H ONVOY SPECTRUM, LLC 730   2023-06-15   

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

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