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: 571 [Rate centres in NPA 571] [Dial plan for NPA 571]

NXX: 523

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-523 A Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
571-523 0 Herndon VA ARTNVAARX8X  551G NUSO, LLC 236      
571-523 1 Herndon VA ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
571-523 2 Herndon VA WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
571-523 3 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
571-523 4 Herndon VA MCLNVA23DS4  8825 LEVEL 3 COMMUNICATIONS, LLC - VA 236      
571-523 5 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
571-523 6 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
571-523 7 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
571-523 8 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
571-523 9 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      

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

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.