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: 581

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-581 A Laconia NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-581 0 Laconia NH   829J PAETEC ITEL, LLC 122      
603-581 1 Laconia NH   829J PAETEC ITEL, LLC 122   2004-11-28   
603-581 2 Laconia NH   829J PAETEC ITEL, LLC 122   2000-08-08   
603-581 3 Laconia NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2015-05-13   
603-581 4 Laconia NH   6386 BELL ATLANTIC MOBILE, INC 122   2007-12-14   
603-581 5 Laconia NH   6386 BELL ATLANTIC MOBILE, INC 122   2008-01-14   
603-581 6 Laconia NH   6386 BELL ATLANTIC MOBILE, INC 122   2008-03-03   
603-581 7 Laconia NH   829J PAETEC ITEL, LLC 122      
603-581 8 Laconia NH   6386 BELL ATLANTIC MOBILE, INC 122   2007-08-02   
603-581 9 Laconia NH   6386 BELL ATLANTIC MOBILE, INC 122   2007-08-02   

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

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