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: 221

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-221 A San Ardo CA   515J IP HORIZON LLC 736      
831-221 0 San Ardo CA   981E BANDWIDTH.COM CLEC, LLC - CA 736   2010-08-30   
831-221 1 San Ardo CA   515J IP HORIZON LLC 736      
831-221 2 San Ardo CA   515J IP HORIZON LLC 736      
831-221 3 San Ardo CA   073H TELNYX LLC 736   2018-07-03   
831-221 4 San Ardo CA   515J IP HORIZON LLC 736   2022-10-20   
831-221 5 San Ardo CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 736   2005-07-31   
831-221 6 San Ardo CA   981E BANDWIDTH.COM CLEC, LLC - CA 736   2015-10-15   
831-221 7 San Ardo CA   515J IP HORIZON LLC 736   2022-10-20   
831-221 8 San Ardo CA   981E BANDWIDTH.COM CLEC, LLC - CA 736   2014-03-28   
831-221 9 San Ardo CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 736   2016-03-05   

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

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