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: 556

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
251-556 A Finchburg AL ATMRALXAXMD  604E ONVOY, LLC - AL 480      
251-556 4 Finchburg AL ATMRALXAXMD  604E ONVOY, LLC - AL 480   2023-07-21   
251-556 5 Finchburg AL ATMRALXAXMD  604E ONVOY, LLC - AL 480   2022-06-01   
251-556 6 Finchburg AL ATMRALXAXMD  604E ONVOY, LLC - AL 480   2022-06-01   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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