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: 635

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
972-635 A Royse City TX RYCYTXNERS0  9533 SOUTHWESTERN BELL 552      
972-635 0 Royse City TX   177F PEERLESS NETWORK OF TEXAS, LLC - TX 552   2013-04-22   
972-635 1 Royse City TX   9533 SOUTHWESTERN BELL 552      
972-635 2 Royse City TX   9533 SOUTHWESTERN BELL 552      
972-635 3 Royse City TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2005-10-09   
972-635 4 Royse City TX   903C ONVOY, LLC - TX 552   2012-07-06   
972-635 5 Royse City TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2004-03-15   
972-635 6 Royse City TX   9533 SOUTHWESTERN BELL 552      
972-635 7 Royse City TX   9533 SOUTHWESTERN BELL 552      
972-635 8 Royse City TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2006-04-09   
972-635 9 Royse City TX   9533 SOUTHWESTERN BELL 552      

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

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