Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 346 [Rate centres in NPA 346] [Dial plan for NPA 346]

NXX: 356

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
346-356 A Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560      
346-356 0 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 1 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 2 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 3 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 4 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 5 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 6 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 7 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 8 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   
346-356 9 Houston TX HSTQTX02DS4  6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2018-09-13   

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

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