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-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
720-996 A Denver CO 939H COMMIO LLC 656      
970-806 A Johnstown-Milliken CO 939H COMMIO LLC 656   2021-12-02   
970-843 A Allison CO 939H COMMIO LLC 656   2022-01-03   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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