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: 640

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
712-640 A Lake City IA RCCYIA100MD  482J WEBSTER-CALHOUN TELEPHONE ASSOCIATION - IA 630      
712-640 0 Lake City IA   221F ONVOY, LLC - IA 630   2021-10-04   
712-640 1 Lake City IA   624H ONVOY SPECTRUM, LLC 630   2024-03-17   
712-640 6 Lake City IA   482J WEBSTER-CALHOUN TELEPHONE ASSOCIATION - IA 630   2021-10-03   
712-640 7 Lake City IA   9877 LEVEL 3 COMMUNICATIONS, LLC - IA 630   2022-11-26   

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

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