Local Calling Guide

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Royse City EMS, TX

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
972-636 A RYCYTXNERS0  9533 SOUTHWESTERN BELL 552      
972-636 0   9533 SOUTHWESTERN BELL 552      
972-636 1   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2006-06-24   
972-636 2   9533 SOUTHWESTERN BELL 552      
972-636 3   9533 SOUTHWESTERN BELL 552      
972-636 4   177F PEERLESS NETWORK OF TEXAS, LLC - TX 552   2013-04-22   
972-636 5   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2006-05-08   
972-636 6   903C ONVOY, LLC - TX 552   2024-01-07   
972-636 7   9533 SOUTHWESTERN BELL 552      
972-636 8   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 552   2006-05-08   
972-636 9   9533 SOUTHWESTERN BELL 552      

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

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