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: 418

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-418 A Exeter NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-418 0 Exeter NH   829J PAETEC ITEL, LLC 122   2000-05-24   
603-418 1 Exeter NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2024-11-17   
603-418 2 Exeter NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2004-02-24   
603-418 3 Exeter NH   829J PAETEC ITEL, LLC 122   2006-06-26   
603-418 4 Exeter NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2009-01-05   
603-418 5 Exeter NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2009-08-21   
603-418 6 Exeter NH   829J PAETEC ITEL, LLC 122      
603-418 7 Exeter NH   318J COMCAST IP PHONE, LLC 122   2014-09-16   
603-418 8 Exeter NH   829J PAETEC ITEL, LLC 122   2000-05-30   
603-418 9 Exeter NH   829J PAETEC ITEL, LLC 122   2000-07-03   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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