Local Calling Guide

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NPA: 956 [Rate centres in NPA 956] [Dial plan for NPA 956]

NXX: 772

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-772 A Port Isabel TX PTISTXSPRS0  9533 SOUTHWESTERN BELL 568      
956-772 0 Port Isabel TX   7138 TELEPORT COMMUNICATIONS AMERICA, LLC - TX 568   2013-04-29   
956-772 1 Port Isabel TX   9533 SOUTHWESTERN BELL 568      
956-772 2 Port Isabel TX   4866 SMARTCOM TELEPHONE, LLC 568   2004-03-17   
956-772 3 Port Isabel TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 568   2007-01-12   
956-772 4 Port Isabel TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 568   2004-05-20   
956-772 5 Port Isabel TX   319D FOREMOST TELECOMMUNICATIONS CORPORATION - TX 568   2005-10-20   
956-772 7 Port Isabel TX   793K TWC IP ENABLED SERVICES, LLC 568   2016-01-25   
956-772 8 Port Isabel TX   516C AT&T CORP. 568   2012-12-07   
956-772 9 Port Isabel TX   9533 SOUTHWESTERN BELL 568      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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