Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 858 [Rate centres in NPA 858] [Dial plan for NPA 858]

NXX: 644

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-644 A San Diego: Mira Mesa DA CA SNDGCA0263Z  965H FRACTEL, LLC 732      
858-644 0 San Diego: Mira Mesa DA CA   073H TELNYX LLC 732   2021-11-28   
858-644 1 San Diego: Mira Mesa DA CA   624H ONVOY SPECTRUM, LLC 732   2021-11-26   
858-644 2 San Diego: Mira Mesa DA CA   624H ONVOY SPECTRUM, LLC 732   2021-11-26   
858-644 3 San Diego: Mira Mesa DA CA   624H ONVOY SPECTRUM, LLC 732   2021-11-26   
858-644 4 San Diego: Mira Mesa DA CA   965H FRACTEL, LLC 732   2021-11-25   
858-644 5 San Diego: Mira Mesa DA CA   624H ONVOY SPECTRUM, LLC 732   2021-11-26   
858-644 6 San Diego: Mira Mesa DA CA   624H ONVOY SPECTRUM, LLC 732   2021-11-26   
858-644 7 San Diego: Mira Mesa DA CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732   2022-10-11   
858-644 8 San Diego: Mira Mesa DA CA   649C ONVOY, LLC - CA 732   2022-12-15   
858-644 9 San Diego: Mira Mesa DA CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2022-06-28   

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

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