Local Calling Guide

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

NXX: 558

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-558 A Claremont NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122      
603-558 0 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 1 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 2 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 3 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 4 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 5 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 6 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2023-07-27   
603-558 7 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2018-10-13   
603-558 8 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-558 9 Claremont NH   6386 BELL ATLANTIC MOBILE, INC 122   2014-01-06   

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

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