Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 856

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-856 A Concord NH MNCHNHCO47Z  829J PAETEC ITEL, LLC 122   2025-04-30   
603-856 0 Concord NH MNCHNHCO47Z  829J PAETEC ITEL, LLC 122      
603-856 1 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2008-07-03   
603-856 3 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2008-11-03   
603-856 4 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2010-11-01   
603-856 5 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2008-10-03   
603-856 6 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2008-05-02   
603-856 7 Concord NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2006-11-30   
603-856 8 Concord NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2006-11-30   
603-856 9 Concord NH MNCHNHCO47Z  829J PAETEC ITEL, LLC 122      

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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