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: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-231 A Clay Center NE LNCLNEXLXFX  549E ONVOY, LLC - NE 958      
531-231 0 Clay Center NE   995E BANDWIDTH.COM CLEC, LLC - NE 958   2022-02-27   
531-231 2 Clay Center NE   549E ONVOY, LLC - NE 958   2019-05-04   
531-231 3 Clay Center NE   549E ONVOY, LLC - NE 958   2020-10-10   
531-231 4 Clay Center NE   549E ONVOY, LLC - NE 958   2020-10-10   
531-231 5 Clay Center NE   549E ONVOY, LLC - NE 958   2021-03-19   
531-231 6 Clay Center NE   549E ONVOY, LLC - NE 958   2021-03-19   
531-231 7 Clay Center NE   5807 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NE 958   2025-09-01   
531-231 8 Clay Center NE   885E GLENWOOD TELECOMMUNICATIONS, INC. - NE 958   2020-02-17   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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