Local Calling Guide

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NPA: 972 [Rate centres in NPA 972] [Dial plan for NPA 972]

NXX: 621

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
972-621 A Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 0 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 1 Irving EMS TX DLLTTX01DMD  5562 METROPCS, INC. 552   2011-07-29   
972-621 2 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 3 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 4 Irving EMS TX IRNGTXXBPS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 5 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 6 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 7 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 8 Irving EMS TX IRNGTXXFDS0  4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 9 Irving EMS TX DLLTTX01DMD  5562 METROPCS, INC. 552   2011-07-29   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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