Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 712 [Rate centres in NPA 712] [Dial plan for NPA 712]

NXX: 397

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
712-397 A Whiting IA SXCYIADT9MD  221F ONVOY, LLC - IA 630      
712-397 0 Whiting IA   515J IP HORIZON LLC 630   2025-10-17   
712-397 1 Whiting IA SXCYIADT9MD  221F ONVOY, LLC - IA 630   2021-02-20   
712-397 2 Whiting IA SXCYIADT9MD  221F ONVOY, LLC - IA 630   2021-02-20   
712-397 7 Whiting IA SXCYIA78X1X  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 630   2023-01-08   

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

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