Local Calling Guide

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

NXX: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-237 A Colebrook NH CLBKNHMARS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-237 1 Colebrook NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-09-10   
603-237 2 Colebrook NH   6386 BELL ATLANTIC MOBILE, INC 122   2018-03-09   
603-237 4 Colebrook NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-237 5 Colebrook NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-237 7 Colebrook NH   829J PAETEC ITEL, LLC 122   2007-07-10   
603-237 8 Colebrook NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-237 9 Colebrook NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      

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

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