Local Calling Guide

Area code/prefix search

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

NXX: 850

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
972-850 A Dallas TX DLLATX37DS6  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552      
972-850 0 Dallas TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552      
972-850 1 Dallas TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552      
972-850 2 Dallas TX   903C ONVOY, LLC - TX 552      
972-850 3 Dallas TX   903C ONVOY, LLC - TX 552      
972-850 4 Dallas TX   9533 SOUTHWESTERN BELL 552      
972-850 5 Dallas TX   829J PAETEC ITEL, LLC 552   2011-07-22   
972-850 6 Dallas TX   004F BANDWIDTH.COM CLEC, LLC - TX 552   2010-11-21   
972-850 7 Dallas TX   903C ONVOY, LLC - TX 552   2009-10-12   
972-850 8 Dallas TX   004F BANDWIDTH.COM CLEC, LLC - TX 552   2010-11-21   
972-850 9 Dallas TX   516C AT&T CORP. 552   2011-03-21   

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

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