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: 865

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-865 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-865 0 Denver CO   5562 METROPCS, INC. 656   2021-10-11   
303-865 1 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-865 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-865 3 Denver CO   026D ONVOY, LLC - CO 656   2005-07-30   
303-865 4 Denver CO   026D ONVOY, LLC - CO 656   2005-07-30   
303-865 5 Denver CO   026D ONVOY, LLC - CO 656   2005-07-30   
303-865 6 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-865 7 Denver CO   026D ONVOY, LLC - CO 656   2005-07-30   
303-865 8 Denver CO   026D ONVOY, LLC - CO 656   2005-07-30   
303-865 9 Denver CO   278F PEERLESS NETWORK OF COLORADO, LLC - CO 656   2021-09-30   

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

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