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: 287

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-287 A Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-287 0 Denver CO   318J COMCAST IP PHONE, LLC 656   2010-06-14   
720-287 1 Denver CO   318J COMCAST IP PHONE, LLC 656   2010-06-14   
720-287 2 Denver CO   318J COMCAST IP PHONE, LLC 656   2010-06-14   
720-287 3 Denver CO   318J COMCAST IP PHONE, LLC 656   2010-06-14   
720-287 4 Denver CO   318J COMCAST IP PHONE, LLC 656   2010-06-14   
720-287 5 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2010-06-16   
720-287 6 Denver CO   026D ONVOY, LLC - CO 656   2010-07-23   
720-287 7 Denver CO   026D ONVOY, LLC - CO 656   2010-07-23   
720-287 8 Denver CO   026D ONVOY, LLC - CO 656   2010-07-23   
720-287 9 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2011-03-18   

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

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