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: 600

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
346-600 A Humble TX HSTNTXYADS5  903C ONVOY, LLC - TX 560      
346-600 0 Humble TX   903C ONVOY, LLC - TX 560   2015-05-25   
346-600 1 Humble TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2015-05-26   
346-600 2 Humble TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2015-05-26   
346-600 3 Humble TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2015-05-26   
346-600 4 Humble TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2015-05-26   
346-600 5 Humble TX   5562 METROPCS, INC. 560   2015-06-23   
346-600 6 Humble TX   903C ONVOY, LLC - TX 560   2015-05-25   
346-600 7 Humble TX   508J CENTURYLINK COMMUNICATIONS, LLC 560   2015-05-26   
346-600 8 Humble TX   5562 METROPCS, INC. 560   2015-06-23   
346-600 9 Humble TX   903C ONVOY, LLC - TX 560   2015-05-25   

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

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