Local Calling Guide

Area code/prefix search

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Dallas, TX

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
972-997 4 DLLSTXRNDS0  9533 SOUTHWESTERN BELL 552      
972-997 5 DLLTTXID1MD  5562 METROPCS, INC. 552   2011-03-24   
972-997 6 DLLTTXID1MD  5562 METROPCS, INC. 552   2011-03-24   
972-997 7 DLLSTXRNDS0  9533 SOUTHWESTERN BELL 552      
972-997 8 DLLSTXRNDS0  9533 SOUTHWESTERN BELL 552      
972-997 9 DLLSTXRNDS0  9533 SOUTHWESTERN BELL 552      

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Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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