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: 515

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-515 A Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656      
303-515 0 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2012-02-09   
303-515 1 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2012-02-09   
303-515 2 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2012-01-10   
303-515 3 Denver CO   026D ONVOY, LLC - CO 656   2012-01-27   
303-515 4 Denver CO   026D ONVOY, LLC - CO 656   2012-01-27   
303-515 5 Denver CO   026D ONVOY, LLC - CO 656   2012-01-27   
303-515 6 Denver CO   026D ONVOY, LLC - CO 656   2012-01-27   
303-515 7 Denver CO   026D ONVOY, LLC - CO 656   2012-01-09   
303-515 8 Denver CO   4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656   2012-02-17   
303-515 9 Denver CO   6529 T-MOBILE USA, INC. 656   2012-03-21   

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

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