Local Calling Guide

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

NXX: 368

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-368 A Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-368 0 Portsmouth NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2021-09-24   
603-368 1 Portsmouth NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2021-09-24   
603-368 2 Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2018-02-26   
603-368 3 Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2018-02-26   
603-368 4 Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2018-02-26   
603-368 5 Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2018-02-26   
603-368 6 Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-06-21   
603-368 7 Portsmouth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-01-31   
603-368 8 Portsmouth NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122   2019-08-30   
603-368 9 Portsmouth NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2021-08-02   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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