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: 525

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
831-525 A King City CA SLNSCA01XXX  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 736      
831-525 0 King City CA   649C ONVOY, LLC - CA 736   2020-08-18   
831-525 1 King City CA   5562 METROPCS, INC. 736   2005-11-02   
831-525 2 King City CA   5562 METROPCS, INC. 736   2006-08-28   
831-525 3 King City CA   5562 METROPCS, INC. 736   2009-06-19   
831-525 4 King City CA   981E BANDWIDTH.COM CLEC, LLC - CA 736   2015-04-27   
831-525 5 King City CA   981E BANDWIDTH.COM CLEC, LLC - CA 736   2010-07-04   
831-525 6 King City CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 736   2012-03-10   
831-525 7 King City CA   073H TELNYX LLC 736   2018-07-03   
831-525 8 King City CA   516C AT&T CORP. 736   2011-09-26   
831-525 9 King City CA   649C ONVOY, LLC - CA 736   2017-04-27   

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

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