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: 721

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-721 A Denver CO DNVRCOMA37Z  507J THE VOICE APPLICATION NETWORK, LLC 656      
720-721 0 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-06-12   
720-721 1 Denver CO DNVRCOMA37Z  507J THE VOICE APPLICATION NETWORK, LLC 656   2016-06-12   
720-721 2 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-06-12   
720-721 3 Denver CO DNVRCOMAXGZ  078F BANDWIDTH.COM CLEC, LLC - CO 656   2016-08-15   
720-721 4 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-09-01   
720-721 5 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-09-01   
720-721 6 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-09-01   
720-721 7 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-06-12   
720-721 8 Denver CO DNVRCOMA32Z  321J HD CARRIER LLC 656   2016-09-01   
720-721 9 Denver CO   321J HD CARRIER LLC 656   2016-09-01   

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

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