Local Calling Guide

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

NXX: 319

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-319 A Portsmouth NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-319 0 Portsmouth NH   829J PAETEC ITEL, LLC 122      
603-319 1 Portsmouth NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-04-23   
603-319 2 Portsmouth NH   829J PAETEC ITEL, LLC 122      
603-319 3 Portsmouth NH   829J PAETEC ITEL, LLC 122      
603-319 4 Portsmouth NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-04-23   
603-319 5 Portsmouth NH   996E BANDWIDTH.COM CLEC, LLC - NH 122   2006-06-22   
603-319 6 Portsmouth NH   318J COMCAST IP PHONE, LLC 122   2013-10-03   
603-319 7 Portsmouth NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2011-03-02   
603-319 8 Portsmouth NH   318J COMCAST IP PHONE, LLC 122   2008-01-22   

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

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