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: DOVRNHTHXEX

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
603-368 A Portsmouth NH 8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-405 A Somersworth NH 8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-570 A Portsmouth NH 8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-602 A Rochester NH 8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-704 A Derry NH 8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-760 A Seabrook NH 8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      

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

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