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: FTWOTXJERP0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
817-413 A Fort Worth TX 9533 SOUTHWESTERN BELL 552      
817-531 A Fort Worth TX 9533 SOUTHWESTERN BELL 552      
817-534 A Fort Worth TX 9533 SOUTHWESTERN BELL 552      
817-535 A Fort Worth TX 9533 SOUTHWESTERN BELL 552      
817-536 A Fort Worth TX 9533 SOUTHWESTERN BELL 552      

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

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