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: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
346-423 A Porter TX HSTNTXMOX7X  318J COMCAST IP PHONE, LLC 560      
346-423 0 Porter TX   318J COMCAST IP PHONE, LLC 560   2020-04-23   
346-423 1 Porter TX   903C ONVOY, LLC - TX 560   2021-02-18   
346-423 2 Porter TX   903C ONVOY, LLC - TX 560   2020-08-23   
346-423 3 Porter TX   903C ONVOY, LLC - TX 560   2020-08-23   
346-423 4 Porter TX   903C ONVOY, LLC - TX 560   2020-08-23   
346-423 5 Porter TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2024-12-20   
346-423 6 Porter TX   903C ONVOY, LLC - TX 560   2021-01-13   
346-423 7 Porter TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2020-04-24   
346-423 8 Porter TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2020-04-24   
346-423 9 Porter TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2020-04-24   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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