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: 738

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-738 A Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656      
720-738 0 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2019-06-08   
720-738 1 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2019-06-08   
720-738 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2019-06-20   
720-738 3 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2019-07-07   
720-738 4 Denver CO   026D ONVOY, LLC - CO 656   2019-05-29   
720-738 5 Denver CO   026D ONVOY, LLC - CO 656   2019-05-29   
720-738 6 Denver CO   026D ONVOY, LLC - CO 656   2019-05-29   
720-738 7 Denver CO   026D ONVOY, LLC - CO 656   2019-05-29   
720-738 8 Denver CO   026D ONVOY, LLC - CO 656   2019-05-29   
720-738 9 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2019-06-08   

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

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