Local Calling Guide

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

NXX: 370

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-370 A Candia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122      
603-370 0 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-370 1 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-370 2 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122   2006-12-02   
603-370 3 Candia NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2010-10-02   
603-370 4 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122   2018-09-20   
603-370 5 Candia NH   9827 OTEL TELEKOM, INC. - NH 122   2011-03-07   
603-370 6 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122   2019-01-04   
603-370 7 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-370 8 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-370 9 Candia NH   6386 BELL ATLANTIC MOBILE, INC 122      

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

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