Local Calling Guide

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NPA: 817 [Rate centres in NPA 817] [Dial plan for NPA 817]

NXX: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
817-423 A Fort Worth TX FTWOTXAXDS0  9533 SOUTHWESTERN BELL 552      
817-423 0 Fort Worth TX   9533 SOUTHWESTERN BELL 552      
817-423 1 Fort Worth TX   9533 SOUTHWESTERN BELL 552      
817-423 2 Fort Worth TX   9533 SOUTHWESTERN BELL 552      
817-423 3 Fort Worth TX   6529 T-MOBILE USA, INC. 552   2025-02-24   
817-423 4 Fort Worth TX   9533 SOUTHWESTERN BELL 552      
817-423 5 Fort Worth TX   9533 SOUTHWESTERN BELL 552      
817-423 6 Fort Worth TX   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 552   2006-08-28   
817-423 7 Fort Worth TX   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 552   2006-08-28   
817-423 8 Fort Worth TX   9533 SOUTHWESTERN BELL 552      
817-423 9 Fort Worth TX   9533 SOUTHWESTERN BELL 552      

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

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