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: 591

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
346-591 A Porter Heights TX HSTNTXMOX7X  318J COMCAST IP PHONE, LLC 560      
346-591 0 Porter Heights TX HSTNTXYADS5  903C ONVOY, LLC - TX 560   2023-08-07   
346-591 1 Porter Heights TX HSTNTXMOX7X  318J COMCAST IP PHONE, LLC 560   2022-11-08   
346-591 2 Porter Heights TX   903C ONVOY, LLC - TX 560   2025-07-19   
346-591 3 Porter Heights TX   903C ONVOY, LLC - TX 560   2025-09-27   
346-591 8 Porter Heights TX HSTNTXYADS5  903C ONVOY, LLC - TX 560   2023-10-14   
346-591 9 Porter Heights TX   903C ONVOY, LLC - TX 560   2025-04-12   

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

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