Local Calling Guide

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

NXX: 287

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-287 A Claremont NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-287 1 Claremont NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-09-10   
603-287 2 Claremont NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2025-06-02   
603-287 3 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2020-08-10   
603-287 4 Claremont NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-287 5 Claremont NH   829J PAETEC ITEL, LLC 122   2010-02-26   
603-287 7 Claremont NH   318J COMCAST IP PHONE, LLC 122   2015-09-14   
603-287 8 Claremont NH   318J COMCAST IP PHONE, LLC 122   2011-07-18   
603-287 9 Claremont NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-05-17   

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

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