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: 242

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-242 A Denver CO DNVRCOSEDS0  9636 QWEST CORPORATION 656      
720-242 0 Denver CO   598J FIVE9, INC. 656   2023-06-16   
720-242 1 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2023-06-24   
720-242 2 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2023-06-24   
720-242 3 Denver CO   9636 QWEST CORPORATION 656   2008-12-15   
720-242 4 Denver CO   9636 QWEST CORPORATION 656   2008-12-15   
720-242 5 Denver CO   026D ONVOY, LLC - CO 656   2008-12-18   
720-242 6 Denver CO   318J COMCAST IP PHONE, LLC 656   2009-01-28   
720-242 7 Denver CO   318J COMCAST IP PHONE, LLC 656   2009-01-28   
720-242 8 Denver CO   318J COMCAST IP PHONE, LLC 656   2009-01-28   
720-242 9 Denver CO   318J COMCAST IP PHONE, LLC 656   2009-01-28   

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

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