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: 536

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-536 A Denver CO DNVRCODCDS0  9636 QWEST CORPORATION 656      
720-536 0 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2008-08-01   
720-536 1 Denver CO DNVRCODCDS0  9636 QWEST CORPORATION 656      
720-536 2 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2007-05-20   
720-536 3 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2007-05-20   
720-536 4 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2007-05-20   
720-536 5 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2007-09-21   
720-536 6 Denver CO DNVRCOCWDS0  9636 QWEST CORPORATION 656      
720-536 7 Denver CO DNVRCOCWDS0  9636 QWEST CORPORATION 656      
720-536 8 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2007-09-21   
720-536 9 Denver CO DNVRCODCDS0  9636 QWEST CORPORATION 656      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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