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: 817

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
346-817 A Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 0 Houston TX   903C ONVOY, LLC - TX 560   2026-09-16   
346-817 1 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 2 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 3 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 4 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 5 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 6 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 7 Houston TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 560   2026-09-15   
346-817 8 Houston TX   903C ONVOY, LLC - TX 560   2026-09-16   
346-817 9 Houston TX   903C ONVOY, LLC - TX 560   2026-09-16   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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