Local Calling Guide

Area code/prefix search

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NPA: 831 [Rate centres in NPA 831] [Dial plan for NPA 831]

NXX: 531

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-531 A Aptos CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722      
831-531 0 Aptos CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722      
831-531 1 Aptos CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722      
831-531 2 Aptos CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722   2005-05-16   
831-531 3 Aptos CA SNJUCACLDS1  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2013-03-29   
831-531 4 Aptos CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722   2004-01-13   
831-531 5 Aptos CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2015-12-30   
831-531 6 Aptos CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2015-12-30   
831-531 7 Aptos CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2010-02-26   
831-531 8 Aptos CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2010-08-28   
831-531 9 Aptos CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2016-01-06   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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