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: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
251-310 A Belle Fontaine AL MOBLALMTXYX  7421 AT&T - LOCAL 480      
251-310 0 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2021-02-17   
251-310 1 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2023-09-23   
251-310 2 Belle Fontaine AL   624H ONVOY SPECTRUM, LLC 480   2024-12-05   
251-310 3 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2020-11-19   
251-310 4 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2020-11-19   
251-310 5 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2021-06-20   
251-310 6 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2021-06-20   
251-310 7 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2021-09-13   
251-310 8 Belle Fontaine AL   604E ONVOY, LLC - AL 480   2021-02-17   
251-310 9 Belle Fontaine AL   7421 AT&T - LOCAL 480   2019-09-02   

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

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