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: IRNGTXXFDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
214-277 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-621 A Irving EMS TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-915 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-916 A Irving EMS TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
972-929 A Irving TX 4344 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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