Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 720 [Rate centres in NPA 720] [Dial plan for NPA 720]

NXX: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-255 A Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 0 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2008-10-09   
720-255 1 Denver CO DNVRCOMAXGZ  078F BANDWIDTH.COM CLEC, LLC - CO 656   2008-11-20   
720-255 2 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2007-03-17   
720-255 3 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 4 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 5 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 6 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 7 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 8 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-255 9 Denver CO DNVRCOII0MD  6529 T-MOBILE USA, INC. 656      

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

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.