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: 309

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-309 A Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 0 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2007-12-04   
303-309 1 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 3 Denver CO   026D ONVOY, LLC - CO 656   2001-07-25   
303-309 4 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 5 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 6 Denver CO   026D ONVOY, LLC - CO 656   2003-09-13   
303-309 7 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 8 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-309 9 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      

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

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