Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 720 [Rate centres in NPA 720] [Dial plan for NPA 720]

NXX: 833

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-833 A Denver CO ENWDCOMADS0  9636 QWEST CORPORATION 656      
720-833 0 Denver CO   9636 QWEST CORPORATION 656      
720-833 1 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2008-12-09   
720-833 2 Denver CO   9636 QWEST CORPORATION 656      
720-833 3 Denver CO   829J PAETEC ITEL, LLC 656   2008-02-04   
720-833 4 Denver CO   026D ONVOY, LLC - CO 656   2007-11-11   
720-833 5 Denver CO   026D ONVOY, LLC - CO 656   2007-11-11   
720-833 6 Denver CO   9636 QWEST CORPORATION 656      
720-833 7 Denver CO   026D ONVOY, LLC - CO 656   2008-04-11   
720-833 8 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2008-12-16   
720-833 9 Denver CO   9636 QWEST CORPORATION 656      

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

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