Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 831 [Rate centres in NPA 831] [Dial plan for NPA 831]

NXX: 401

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-401 A Ben Lomond CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722      
831-401 2 Ben Lomond CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722      
831-401 3 Ben Lomond CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722      
831-401 4 Ben Lomond CA   649C ONVOY, LLC - CA 722   2022-02-26   
831-401 5 Ben Lomond CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2019-03-23   
831-401 6 Ben Lomond CA   624H ONVOY SPECTRUM, LLC 722   2021-11-07   
831-401 7 Ben Lomond CA   624H ONVOY SPECTRUM, LLC 722   2021-11-07   
831-401 8 Ben Lomond CA   553J WHITESKY COMMUNICATIONS, LLC 722   2021-09-16   
831-401 9 Ben Lomond CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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