Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Switch: IRNGTXXADS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
972-252 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-255 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-256 A Irving EMS TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-257 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-258 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-261 A Irving EMS TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-413 A Irving EMS TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-570 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-594 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-607 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-659 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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