Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 972 [Rate centres in NPA 972] [Dial plan for NPA 972]

NXX: 940

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
972-940 A Dallas TX DLLSTXNODS0  9533 SOUTHWESTERN BELL 552      
972-940 0 Dallas TX   6529 T-MOBILE USA, INC. 552   2017-04-07   
972-940 1 Dallas TX   6529 T-MOBILE USA, INC. 552   2017-04-07   
972-940 2 Dallas TX   6529 T-MOBILE USA, INC. 552   2017-04-07   
972-940 3 Dallas TX   6529 T-MOBILE USA, INC. 552   2017-07-25   
972-940 4 Dallas TX   6529 T-MOBILE USA, INC. 552   2017-04-07   
972-940 5 Dallas TX   6529 T-MOBILE USA, INC. 552   2017-07-25   
972-940 6 Dallas TX DLLSTXNODS0  9533 SOUTHWESTERN BELL 552   2017-02-23   
972-940 7 Dallas TX DLLSTXNODS0  9533 SOUTHWESTERN BELL 552   2017-02-23   
972-940 8 Dallas TX FTWOTXEDX1Z  7148 TELEPORT COMMUNICATIONS AMERICA, LLC - TX 552   2017-09-08   
972-940 9 Dallas TX FTWOTXEDX1Z  7148 TELEPORT COMMUNICATIONS AMERICA, LLC - TX 552   2017-09-08   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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