Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 424 [Rate centres in NPA 424] [Dial plan for NPA 424]

NXX: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
424-437 A Hawthorne CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730      
424-437 0 Hawthorne CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2019-10-23   
424-437 1 Hawthorne CA   073H TELNYX LLC 730   2020-11-23   
424-437 2 Hawthorne CA   649C ONVOY, LLC - CA 730   2021-07-12   
424-437 3 Hawthorne CA   197D VONAGE AMERICA LLC 730   2020-06-12   
424-437 4 Hawthorne CA   649C ONVOY, LLC - CA 730   2021-07-12   
424-437 5 Hawthorne CA   197D VONAGE AMERICA LLC 730   2020-06-12   
424-437 6 Hawthorne CA   649C ONVOY, LLC - CA 730   2021-07-12   
424-437 7 Hawthorne CA   6529 T-MOBILE USA, INC. 730   2025-09-24   
424-437 8 Hawthorne CA   649C ONVOY, LLC - CA 730   2021-07-12   
424-437 9 Hawthorne CA   6529 T-MOBILE USA, INC. 730   2019-10-04   

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

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