Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 339

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-339 A Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656      
303-339 0 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656   2005-07-18   
303-339 1 Denver CO   026D ONVOY, LLC - CO 656   2004-08-28   
303-339 2 Denver CO   026D ONVOY, LLC - CO 656   2004-08-28   
303-339 3 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2007-08-23   
303-339 4 Denver CO   026D ONVOY, LLC - CO 656   2004-04-12   
303-339 5 Denver CO   026D ONVOY, LLC - CO 656   2004-04-12   
303-339 6 Denver CO   026D ONVOY, LLC - CO 656   2004-07-10   
303-339 7 Denver CO   026D ONVOY, LLC - CO 656   2004-07-10   
303-339 8 Denver CO   026D ONVOY, LLC - CO 656   2004-07-10   
303-339 9 Denver CO   026D ONVOY, LLC - CO 656   2004-08-28   

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

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