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: 521

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
251-521 A Grand Bay AL MOBLALAZX6Z  604E ONVOY, LLC - AL 480      
251-521 0 Grand Bay AL   939H COMMIO, LLC 480   2022-05-20   
251-521 1 Grand Bay AL   072F BANDWIDTH.COM CLEC, LLC - AL 480   2022-10-22   
251-521 2 Grand Bay AL   604E ONVOY, LLC - AL 480   2021-11-05   
251-521 3 Grand Bay AL   604E ONVOY, LLC - AL 480   2021-11-05   
251-521 4 Grand Bay AL   604E ONVOY, LLC - AL 480   2022-03-25   
251-521 5 Grand Bay AL   604E ONVOY, LLC - AL 480   2022-03-25   
251-521 6 Grand Bay AL   604E ONVOY, LLC - AL 480   2023-06-09   
251-521 7 Grand Bay AL   5255 LEVEL 3 COMMUNICATIONS, LLC - AL 480   2023-03-10   
251-521 8 Grand Bay AL   072F BANDWIDTH.COM CLEC, LLC - AL 480   2022-10-22   
251-521 9 Grand Bay AL   072F BANDWIDTH.COM CLEC, LLC - AL 480   2021-12-19   

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

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