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: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-604 A Denver CO DNVRCOMAXGZ  078F BANDWIDTH.COM CLEC, LLC - CO 656      
720-604 0 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2023-02-19   
720-604 1 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2023-02-19   
720-604 2 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2023-02-19   
720-604 3 Denver CO   026D ONVOY, LLC - CO 656   2023-02-20   
720-604 4 Denver CO   026D ONVOY, LLC - CO 656   2023-02-20   
720-604 5 Denver CO   026D ONVOY, LLC - CO 656   2023-02-20   
720-604 6 Denver CO   624H ONVOY SPECTRUM, LLC 656   2023-08-01   
720-604 7 Denver CO   624H ONVOY SPECTRUM, LLC 656   2023-08-01   
720-604 8 Denver CO   624H ONVOY SPECTRUM, LLC 656   2023-08-01   
720-604 9 Denver CO   624H ONVOY SPECTRUM, LLC 656   2023-08-01   

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

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