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: 531

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-531 A Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-531 0 Denver CO HLRNCOFP1MD  508J CENTURYLINK COMMUNICATIONS, LLC 656      
720-531 1 Denver CO HLRNCOFP1MD  508J CENTURYLINK COMMUNICATIONS, LLC 656      
720-531 2 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-531 3 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-531 4 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-531 5 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656      
720-531 6 Denver CO HLRNCOFP1MD  508J CENTURYLINK COMMUNICATIONS, LLC 656      
720-531 7 Denver CO HLRNCOFP1MD  508J CENTURYLINK COMMUNICATIONS, LLC 656      
720-531 8 Denver CO HLRNCOFP1MD  508J CENTURYLINK COMMUNICATIONS, LLC 656      
720-531 9 Denver CO HLRNCOFP1MD  508J CENTURYLINK COMMUNICATIONS, LLC 656      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.