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: 687

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-687 A Aptos CA APTSCA12DS0  9740 PACIFIC BELL 722      
831-687 0 Aptos CA   9740 PACIFIC BELL 722      
831-687 1 Aptos CA   9740 PACIFIC BELL 722      
831-687 2 Aptos CA   9262 UTILITY TELECOM GROUP, LLC - CA 722   2006-06-14   
831-687 4 Aptos CA   649C ONVOY, LLC - CA 722   2016-01-06   
831-687 5 Aptos CA   9740 PACIFIC BELL 722      
831-687 7 Aptos CA   433E SONIC TELECOM, LLC - CA 722   2012-12-22   
831-687 8 Aptos CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2011-07-29   
831-687 9 Aptos CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2011-07-29   

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

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