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: 420

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-420 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-420 0 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2010-09-19   
720-420 1 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2010-07-17   
720-420 2 Denver CO DNVTCOUZAMD  4788 MCLEODUSA TELECOMMUNICATION SERVICES, INC. - CO 656   2010-08-04   
720-420 3 Denver CO DNVRCO03DS1  5972 INTERLINK ADV SVC DBA FORETHOUGHT.NET - CO 656   2010-07-29   
720-420 4 Denver CO DNVRCO03DS1  5972 INTERLINK ADV SVC DBA FORETHOUGHT.NET - CO 656   2010-07-29   
720-420 5 Denver CO DNVRCO03DS1  5972 INTERLINK ADV SVC DBA FORETHOUGHT.NET - CO 656   2010-07-29   
720-420 6 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2010-08-14   
720-420 7 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2010-08-14   
720-420 8 Denver CO DNVTCOUZAMD  4788 MCLEODUSA TELECOMMUNICATION SERVICES, INC. - CO 656   2010-08-04   
720-420 9 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2010-09-19   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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