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: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
820-400 A Parkfield CA SNLOCA01XLY  506J TWILIO INTERNATIONAL, INC. 740      
820-400 0 Parkfield CA SNLOCA01XFX  649C ONVOY, LLC - CA 740   2019-03-01   
820-400 1 Parkfield CA SNLOCA01XFX  649C ONVOY, LLC - CA 740   2019-03-01   
820-400 2 Parkfield CA SNLOCA01XFX  649C ONVOY, LLC - CA 740   2021-03-04   
820-400 3 Parkfield CA SNLOCA01XFX  649C ONVOY, LLC - CA 740   2021-03-04   
820-400 4 Parkfield CA SNBBCAXFXIY  965H FRACTEL, LLC 740   2019-07-16   
820-400 5 Parkfield CA SNLOCA01XFX  649C ONVOY, LLC - CA 740   2021-07-30   
820-400 6 Parkfield CA SNLOCA01XFY  516J TON80 COMMUNICATIONS, LLC 740   2021-10-30   
820-400 8 Parkfield CA SNBBCAXFXFY  624H ONVOY SPECTRUM, LLC 740   2025-01-30   
820-400 9 Parkfield CA SNLOCA01XLY  506J TWILIO INTERNATIONAL, INC. 740   2022-06-17   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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