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: 313

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-313 A Keene NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-313 0 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 1 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 2 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 3 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 4 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 5 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 6 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 7 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 8 Keene NH   6290 UNITED STATES CELLULAR - NH 122      
603-313 9 Keene NH   6290 UNITED STATES CELLULAR - NH 122      

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.