Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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NPA: 350 [Rate centres in NPA 350] [Dial plan for NPA 350]

NXX: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
350-237 A Patterson CA   624H ONVOY SPECTRUM, LLC 738   2025-02-27   
350-237 0 Patterson CA   624H ONVOY SPECTRUM, LLC 738   2025-02-27   
350-237 1 Patterson CA   649C ONVOY, LLC - CA 738   2025-05-27   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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