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: 550

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
350-550 A Moccasin CA SKTNCA01XKZ  624H ONVOY SPECTRUM, LLC 738   2024-01-15   
350-550 0 Moccasin CA SKTNCA01XKZ  624H ONVOY SPECTRUM, LLC 738   2024-01-15   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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