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: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 956

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-956 A Portsmouth NH MNCHNHCO18Z  197D VONAGE AMERICA LLC 122      
603-956 0 Portsmouth NH MNCHNHAC3MD  939H COMMIO, LLC 122      
603-956 1 Portsmouth NH MNCHNHCO23Z  073H TELNYX LLC 122      
603-956 2 Portsmouth NH MNCHNHCO18Z  197D VONAGE AMERICA LLC 122      
603-956 3 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122      
603-956 4 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122      
603-956 5 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122      
603-956 6 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122      
603-956 7 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122      
603-956 8 Portsmouth NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-956 9 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122      

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

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.