Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 251 [Rate centres in NPA 251] [Dial plan for NPA 251]

NXX: 523

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
251-523 A Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480      
251-523 0 Mount Vernon AL MOBLALAZ13Z  624H ONVOY SPECTRUM, LLC 480   2023-04-29   
251-523 1 Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480   2023-09-23   
251-523 2 Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480   2021-11-05   
251-523 3 Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480   2021-11-05   
251-523 4 Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480   2022-03-25   
251-523 5 Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480   2022-03-25   
251-523 6 Mount Vernon AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480   2023-06-09   
251-523 7 Mount Vernon AL MOBLALAZ13Z  624H ONVOY SPECTRUM, LLC 480   2023-10-27   
251-523 8 Mount Vernon AL MOBLALAZ13Z  624H ONVOY SPECTRUM, LLC 480   2023-10-27   
251-523 9 Mount Vernon AL MOBLALAZ13Z  624H ONVOY SPECTRUM, LLC 480   2023-10-27   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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