Local Calling Guide

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NPA: 713 [Rate centres in NPA 713] [Dial plan for NPA 713]

NXX: 321

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
713-321 A Houston TX HSTNTXCLDS0  9533 SOUTHWESTERN BELL 560      
713-321 0 Houston TX HSTNTX01G04  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2014-05-04   
713-321 1 Houston TX HSTOTX42DS2  7074 LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 560   2013-08-11   
713-321 2 Houston TX HSTNTXGI0MD  004F BANDWIDTH.COM CLEC, LLC - TX 560   2014-05-12   
713-321 3 Houston TX HSTNTXCLDS0  9533 SOUTHWESTERN BELL 560      
713-321 4 Houston TX HSTNTXCLDS0  9533 SOUTHWESTERN BELL 560      
713-321 5 Houston TX HSTNTXCLDS0  9533 SOUTHWESTERN BELL 560      
713-321 6 Houston TX HSTNTXCLDS0  9533 SOUTHWESTERN BELL 560      
713-321 7 Houston TX HSTNTXCLDS0  9533 SOUTHWESTERN BELL 560      
713-321 8 Houston TX HSTNTX01G04  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2014-05-04   
713-321 9 Houston TX HSTNTX01G04  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2014-05-04   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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