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: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-310 A Bedford NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-310 0 Bedford NH   9827 OTEL TELEKOM, INC. - NH 122   2004-10-09   
603-310 1 Bedford NH   073H TELNYX LLC 122   2022-10-27   
603-310 2 Bedford NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2002-11-15   
603-310 3 Bedford NH   829J PAETEC ITEL, LLC 122   2007-05-04   
603-310 4 Bedford NH   829J PAETEC ITEL, LLC 122   2002-09-10   
603-310 5 Bedford NH   829J PAETEC ITEL, LLC 122   2015-03-03   
603-310 6 Bedford NH   7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122   2020-03-24   
603-310 7 Bedford NH   318J COMCAST IP PHONE, LLC 122   2015-01-12   
603-310 8 Bedford NH   939H COMMIO, LLC 122   2022-11-05   
603-310 9 Bedford NH   829J PAETEC ITEL, LLC 122   2001-01-05   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.