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: 327

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-327 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-327 0 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2022-05-19   
303-327 1 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-327 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-327 3 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-327 4 Denver CO   026D ONVOY, LLC - CO 656   2004-02-25   
303-327 5 Denver CO   026D ONVOY, LLC - CO 656   2004-02-25   
303-327 6 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-327 7 Denver CO   026D ONVOY, LLC - CO 656   2004-02-25   
303-327 8 Denver CO   026D ONVOY, LLC - CO 656   2005-01-01   
303-327 9 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      

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

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