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: 240

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-240 A Herndon VA BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
571-240 0 Herndon VA VINNVACBDS0  138E ONVOY, LLC - VA 236   2024-01-18   
571-240 1 Herndon VA WASHDC127MD  073H TELNYX LLC 236   2024-01-26   
571-240 2 Herndon VA   138E ONVOY, LLC - VA 236   2024-04-11   
571-240 3 Herndon VA   073H TELNYX LLC 236   2024-04-19   
571-240 4 Herndon VA   138E ONVOY, LLC - VA 236   2024-04-15   
571-240 5 Herndon VA   138E ONVOY, LLC - VA 236   2024-04-15   
571-240 8 Herndon VA BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-11-16   
571-240 9 Herndon VA BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-11-16   

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

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.