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: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-257 A Valentine NE OMAHNE16X9X  710A ALLO COMMUNICATIONS, LLC - NE 644      
531-257 0 Valentine NE   6263 UNITED STATES CELLULAR - NE 644   2021-05-13   
531-257 1 Valentine NE   073H TELNYX LLC 644   2021-06-04   
531-257 2 Valentine NE   995E BANDWIDTH.COM CLEC, LLC - NE 644   2022-07-15   
531-257 3 Valentine NE   939H COMMIO, LLC 644   2024-02-12   
531-257 4 Valentine NE   6701 AERIAL COMMUNICATIONS, INC. 644   2023-11-10   
531-257 5 Valentine NE   710A ALLO COMMUNICATIONS, LLC - NE 644   2021-04-29   
531-257 6 Valentine NE   549E ONVOY, LLC - NE 644   2021-04-30   
531-257 7 Valentine NE   549E ONVOY, LLC - NE 644   2021-06-03   
531-257 8 Valentine NE   939H COMMIO, LLC 644   2021-11-18   
531-257 9 Valentine NE   939H COMMIO, LLC 644   2021-11-18   

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

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