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: 621

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
712-621 A Red Oak IA CRRLIAAF0MD  6266 UNITED STATES CELLULAR - IA 644      
712-621 0 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 1 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 2 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 3 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 4 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 5 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 6 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 7 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 8 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      
712-621 9 Red Oak IA   6266 UNITED STATES CELLULAR - IA 644      

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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