Local Calling Guide

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

NXX: 518

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-518 A Manchester NH MNCHNHCO37Z  7421 AT&T - LOCAL 122      
603-518 0 Manchester NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2020-02-09   
603-518 1 Manchester NH   829J PAETEC ITEL, LLC 122   2001-05-01   
603-518 2 Manchester NH   829J PAETEC ITEL, LLC 122   2002-06-15   
603-518 3 Manchester NH   829J PAETEC ITEL, LLC 122   2006-05-03   
603-518 4 Manchester NH   829J PAETEC ITEL, LLC 122   2006-10-26   
603-518 5 Manchester NH   318J COMCAST IP PHONE, LLC 122   2008-10-16   
603-518 6 Manchester NH   637E ONVOY, LLC - NH 122   2021-04-01   
603-518 7 Manchester NH   318J COMCAST IP PHONE, LLC 122   2012-05-24   
603-518 8 Manchester NH   318J COMCAST IP PHONE, LLC 122   2013-02-09   
603-518 9 Manchester NH   7421 AT&T - LOCAL 122      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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