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: 491

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
712-491 A Sioux City IA   221F ONVOY, LLC - IA 630   2026-09-18   
712-491 0 Sioux City IA   221F ONVOY, LLC - IA 630   2026-09-18   
712-491 1 Sioux City IA   221F ONVOY, LLC - IA 630   2026-09-18   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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