Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 350 [Rate centres in NPA 350] [Dial plan for NPA 350]

NXX: 750

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
350-750 A Sonora: Main DA CA SKTNCA01XKZ  624H ONVOY SPECTRUM, LLC 738   2024-01-19   
350-750 0 Sonora: Main DA CA   624H ONVOY SPECTRUM, LLC 738   2024-01-19   
350-750 1 Sonora: Main DA CA   073H TELNYX LLC 738   2024-01-20   
350-750 2 Sonora: Main DA CA   6529 T-MOBILE USA, INC. 738   2025-01-20   
350-750 3 Sonora: Main DA CA   649C ONVOY, LLC - CA 738   2025-12-14   
350-750 4 Sonora: Main DA CA   649C ONVOY, LLC - CA 738   2025-05-10   
350-750 7 Sonora: Main DA CA   6529 T-MOBILE USA, INC. 738   2024-09-27   
350-750 8 Sonora: Main DA CA   649C ONVOY, LLC - CA 738   2024-07-15   
350-750 9 Sonora: Main DA CA   649C ONVOY, LLC - CA 738   2024-06-07   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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