Local Calling Guide

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

NXX: 631

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-631 A Lancaster NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-631 0 Lancaster NH   6290 UNITED STATES CELLULAR - NH 122      
603-631 1 Lancaster NH   6290 UNITED STATES CELLULAR - NH 122      
603-631 2 Lancaster NH   6290 UNITED STATES CELLULAR - NH 122      
603-631 3 Lancaster NH   6290 UNITED STATES CELLULAR - NH 122      
603-631 4 Lancaster NH   6386 BELL ATLANTIC MOBILE, INC 122   2011-04-01   
603-631 5 Lancaster NH   6386 BELL ATLANTIC MOBILE, INC 122   2009-03-16   
603-631 6 Lancaster NH   6386 BELL ATLANTIC MOBILE, INC 122   2012-07-15   
603-631 7 Lancaster NH   6386 BELL ATLANTIC MOBILE, INC 122   2014-08-01   
603-631 9 Lancaster NH   6290 UNITED STATES CELLULAR - NH 122      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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