Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-320 A Grafton NE LNCLNEXLXFX  549E ONVOY, LLC - NE 958      
531-320 0 Grafton NE LNCLNEXLXFX  549E ONVOY, LLC - NE 958   2023-07-22   
531-320 1 Grafton NE LNCLNEXLX2Y  624H ONVOY SPECTRUM, LLC 958   2024-03-09   
531-320 4 Grafton NE LNCLNEXLXFX  549E ONVOY, LLC - NE 958   2023-06-15   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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