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: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-303 A Denver IA CDRRIAAXQMD  444G AUREON COMMUNICATIONS, LLC 635      
319-303 1 Denver IA CDRRIAAXQMD  444G AUREON COMMUNICATIONS, LLC 635   2021-12-18   
319-303 2 Denver IA CDRRIADTHMD  624H ONVOY SPECTRUM, LLC 635   2024-12-19   
319-303 7 Denver IA CDRRIADT1MD  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 635   2023-01-08   
319-303 8 Denver IA   515J IP HORIZON LLC 635   2025-08-14   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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