Local Calling Guide

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

NXX: 373

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-373 A Portsmouth NH NASHNH08AMD  4053 CONVERSENT COMMUNICATIONS OF NEW HAMPSHIRE, LLC 122      
603-373 0 Portsmouth NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2001-01-01   
603-373 1 Portsmouth NH MNCHNHCOXMX  4206 PAETEC COMMUNICATIONS, INC. - NH 122   2004-11-01   
603-373 2 Portsmouth NH MNCHNHCO37Z  7421 AT&T - LOCAL 122   2001-07-01   
603-373 3 Portsmouth NH   145J TERRA NOVA TELECOM INC. 122   2021-05-27   
603-373 4 Portsmouth NH MNCHNHCOX1Y  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2004-04-18   
603-373 5 Portsmouth NH   4053 CONVERSENT COMMUNICATIONS OF NEW HAMPSHIRE, LLC 122      
603-373 6 Portsmouth NH NASHNH08AMD  4053 CONVERSENT COMMUNICATIONS OF NEW HAMPSHIRE, LLC 122      
603-373 7 Portsmouth NH NASHNH08AMD  4053 CONVERSENT COMMUNICATIONS OF NEW HAMPSHIRE, LLC 122   2005-08-05   
603-373 8 Portsmouth NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2003-02-04   
603-373 9 Portsmouth NH MNCHNHCOX9Y  2527 CHOICE ONE OF NEW HAMPSHIRE, INC. 122   2000-07-03   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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