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: 312

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-312 A Tamora NE LNCLNEXLXKX  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 958      
531-312 0 Tamora NE   549E ONVOY, LLC - NE 958   2023-07-22   
531-312 1 Tamora NE   624H ONVOY SPECTRUM, LLC 958   2024-03-16   
531-312 9 Tamora NE   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 958   2022-11-07   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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