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.

Switch: ROCHNHWE4MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
603-457 A Dover NH 314C IDT AMERICA, CORP. - NH 122      
603-701 A New Durham NH 314C IDT AMERICA, CORP. - NH 122      
603-813 A Center Barnstead NH 314C IDT AMERICA, CORP. - NH 122      
603-855 A Alton NH 314C IDT AMERICA, CORP. - NH 122      
603-872 A Gilmanton Iron Works NH 314C IDT AMERICA, CORP. - NH 122      
603-906 A Barnstead NH 314C IDT AMERICA, CORP. - NH 122      
603-948 A Rochester NH 314C IDT AMERICA, CORP. - NH 122      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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