Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 820 [Rate centres in NPA 820] [Dial plan for NPA 820]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
820-666 A San Luis Obispo CA SNBBCAXFXIY  965H FRACTEL, LLC 740      
820-666 0 San Luis Obispo CA   649C ONVOY, LLC - CA 740   2025-04-06   
820-666 2 San Luis Obispo CA SNBBCAXFXFY  624H ONVOY SPECTRUM, LLC 740   2020-06-29   
820-666 3 San Luis Obispo CA SNBBCAXFXFY  624H ONVOY SPECTRUM, LLC 740   2020-06-29   
820-666 4 San Luis Obispo CA SNBBCAXFXFY  624H ONVOY SPECTRUM, LLC 740   2020-06-29   
820-666 6 San Luis Obispo CA SNBBCAXFXIY  965H FRACTEL, LLC 740   2019-03-23   
820-666 8 San Luis Obispo CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 740   2025-02-13   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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