Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 319 [Rate centres in NPA 319] [Dial plan for NPA 319]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-666 A Cedar Falls IA IWCYIA706MD  965H FRACTEL, LLC 635      
319-666 0 Cedar Falls IA   423H AIRUS, INC - IA 635   2019-05-23   
319-666 1 Cedar Falls IA   073H TELNYX LLC 635   2019-06-16   
319-666 2 Cedar Falls IA   6266 UNITED STATES CELLULAR - IA 635   2020-11-08   
319-666 3 Cedar Falls IA   221F ONVOY, LLC - IA 635   2019-09-19   
319-666 4 Cedar Falls IA   221F ONVOY, LLC - IA 635   2019-09-19   
319-666 5 Cedar Falls IA   221F ONVOY, LLC - IA 635   2024-02-04   
319-666 6 Cedar Falls IA   965H FRACTEL, LLC 635   2019-03-26   
319-666 7 Cedar Falls IA   221F ONVOY, LLC - IA 635   2021-03-14   
319-666 8 Cedar Falls IA   221F ONVOY, LLC - IA 635   2021-03-14   
319-666 9 Cedar Falls IA   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 635   2019-09-01   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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