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: 381

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-381 A Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-381 0 Denver CO   318J COMCAST IP PHONE, LLC 656   2005-09-24   
720-381 1 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2006-11-12   
720-381 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2006-11-12   
720-381 3 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2006-11-12   
720-381 4 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2006-11-12   
720-381 5 Denver CO   829J PAETEC ITEL, LLC 656   2009-01-01   
720-381 6 Denver CO   318J COMCAST IP PHONE, LLC 656   2006-12-29   
720-381 7 Denver CO   6529 T-MOBILE USA, INC. 656   2007-04-21   
720-381 8 Denver CO   6529 T-MOBILE USA, INC. 656   2007-04-21   
720-381 9 Denver CO   6529 T-MOBILE USA, INC. 656   2007-04-21   

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

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