Local Calling Guide

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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-331 A Colebrook NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-331 0 Colebrook NH   9827 OTEL TELEKOM, INC. - NH 122   2010-08-05   
603-331 1 Colebrook NH   6386 BELL ATLANTIC MOBILE, INC 122   2009-03-16   
603-331 2 Colebrook NH   6386 BELL ATLANTIC MOBILE, INC 122   2010-09-02   
603-331 3 Colebrook NH   6386 BELL ATLANTIC MOBILE, INC 122   2014-05-14   
603-331 4 Colebrook NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-331 5 Colebrook NH   6386 BELL ATLANTIC MOBILE, INC 122   2012-10-12   
603-331 6 Colebrook NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2020-10-26   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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