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: 406

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-406 A Denver IA CDRRIAAB4MD  7421 AT&T - LOCAL 635      
319-406 0 Denver IA   593K MCC TELEPHONY LLC 635   2010-05-09   
319-406 1 Denver IA   7421 AT&T - LOCAL 635      
319-406 2 Denver IA   985E BANDWIDTH.COM CLEC, LLC - IA 635   2015-05-08   
319-406 3 Denver IA   221F ONVOY, LLC - IA 635   2018-04-13   
319-406 4 Denver IA   073H TELNYX LLC 635   2018-06-27   
319-406 5 Denver IA   221F ONVOY, LLC - IA 635   2021-03-14   
319-406 6 Denver IA   221F ONVOY, LLC - IA 635   2019-09-19   
319-406 7 Denver IA   221F ONVOY, LLC - IA 635   2008-09-04   
319-406 8 Denver IA   544H INTEGRATED PATH COMMUNCATIONS, LLC - IA 635   2018-05-11   
319-406 9 Denver IA   221F ONVOY, LLC - IA 635   2021-04-24   

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

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