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: 501

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
442-501 A Imperial CA   649C ONVOY, LLC - CA 732   2026-05-30   
442-501 0 Imperial CA   649C ONVOY, LLC - CA 732   2026-05-30   
442-501 1 Imperial CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 732   2026-07-06   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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