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: 586

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-586 A Jefferson NH JFSNNHYARS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-586 0 Jefferson NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-09-15   
603-586 4 Jefferson NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-586 5 Jefferson NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2003-03-23   
603-586 6 Jefferson NH   793K TWC IP ENABLED SERVICES, LLC 122   2012-10-02   
603-586 7 Jefferson NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-586 9 Jefferson NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122   2014-06-20   

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

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