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: 225

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-225 A Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 0 Denver CO   026D ONVOY, LLC - CO 656   2003-04-06   
303-225 1 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 3 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 4 Denver CO   026D ONVOY, LLC - CO 656   2003-04-06   
303-225 5 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 6 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 7 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-225 8 Denver CO   026D ONVOY, LLC - CO 656   2003-04-06   
303-225 9 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      

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

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