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: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 242

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-242 A Denver CO DNVRCO37DS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
303-242 0 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656   2011-08-19   
303-242 1 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2006-08-21   
303-242 2 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2006-09-14   
303-242 3 Denver CO DNVRCO37DS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
303-242 4 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2006-09-14   
303-242 5 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2005-02-19   
303-242 6 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2006-09-21   
303-242 7 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2006-09-14   
303-242 8 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2005-02-02   
303-242 9 Denver CO AURRCO20AMD  6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2006-09-21   

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

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.