Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 972 [Rate centres in NPA 972] [Dial plan for NPA 972]

NXX: 528

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
972-528 A Dallas TX DLLSTXRNDS0  9533 SOUTHWESTERN BELL 552      
972-528 0 Dallas TX   004F BANDWIDTH.COM CLEC, LLC - TX 552   2010-06-17   
972-528 1 Dallas TX   9533 SOUTHWESTERN BELL 552      
972-528 2 Dallas TX   9533 SOUTHWESTERN BELL 552      
972-528 3 Dallas TX   9533 SOUTHWESTERN BELL 552      
972-528 4 Dallas TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2011-06-19   
972-528 5 Dallas TX   903C ONVOY, LLC - TX 552   2011-04-22   
972-528 6 Dallas TX   903C ONVOY, LLC - TX 552   2010-04-10   
972-528 7 Dallas TX   177F PEERLESS NETWORK OF TEXAS, LLC - TX 552   2012-04-06   
972-528 8 Dallas TX   004F BANDWIDTH.COM CLEC, LLC - TX 552   2010-06-17   
972-528 9 Dallas TX   004F BANDWIDTH.COM CLEC, LLC - TX 552   2010-06-17   

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

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