Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 499

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-499 A Keene NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-499 0 Keene NH   6290 UNITED STATES CELLULAR - NH 122   2003-12-30   
603-499 1 Keene NH   6290 UNITED STATES CELLULAR - NH 122   2003-12-30   
603-499 2 Keene NH   6290 UNITED STATES CELLULAR - NH 122   2003-12-30   
603-499 3 Keene NH   6290 UNITED STATES CELLULAR - NH 122   2003-12-30   
603-499 4 Keene NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-499 5 Keene NH   6290 UNITED STATES CELLULAR - NH 122   2003-12-30   
603-499 6 Keene NH   6290 UNITED STATES CELLULAR - NH 122   2003-12-30   
603-499 7 Keene NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-07-15   
603-499 8 Keene NH   793K TWC IP ENABLED SERVICES, LLC 122   2014-11-05   
603-499 9 Keene NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2023-02-10   

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

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