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: 606

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-606 A Manchester NH DOVRNHTHGMD  624H ONVOY SPECTRUM, LLC 122      
603-606 0 Manchester NH DOVRNHTHGMD  624H ONVOY SPECTRUM, LLC 122   2019-12-02   
603-606 1 Manchester NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2006-05-18   
603-606 2 Manchester NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2006-05-18   
603-606 3 Manchester NH   829J PAETEC ITEL, LLC 122   2006-03-27   
603-606 4 Manchester NH   829J PAETEC ITEL, LLC 122   2004-09-13   
603-606 5 Manchester NH   829J PAETEC ITEL, LLC 122      
603-606 6 Manchester NH   829J PAETEC ITEL, LLC 122      
603-606 7 Manchester NH   829J PAETEC ITEL, LLC 122   2003-05-13   
603-606 8 Manchester NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2017-05-26   
603-606 9 Manchester NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2019-12-02   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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