Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 956 [Rate centres in NPA 956] [Dial plan for NPA 956]

NXX: 577

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-577 A Harlingen TX HRLNTXHGDS0  9533 SOUTHWESTERN BELL 568      
956-577 0 Harlingen TX HRLNTXHGDS0  9533 SOUTHWESTERN BELL 568   2016-03-18   
956-577 1 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2008-05-18   
956-577 2 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2008-05-18   
956-577 3 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2008-05-18   
956-577 4 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2008-05-18   
956-577 5 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2008-05-18   
956-577 6 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2008-05-18   
956-577 7 Harlingen TX HRLNTXHGX7X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 568   2007-01-09   
956-577 8 Harlingen TX   145J TERRA NOVA TELECOM INC. 568   2024-05-10   
956-577 9 Harlingen TX HRLNTXDU7MD  145J TERRA NOVA TELECOM INC. 568   2023-01-14   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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