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: 601

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-601 A Hampton NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-601 0 Hampton NH   829J PAETEC ITEL, LLC 122   2001-04-09   
603-601 1 Hampton NH   829J PAETEC ITEL, LLC 122   2004-02-21   
603-601 2 Hampton NH   318J COMCAST IP PHONE, LLC 122   2002-08-05   
603-601 3 Hampton NH   829J PAETEC ITEL, LLC 122   2011-02-23   
603-601 4 Hampton NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-09-05   
603-601 5 Hampton NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2013-01-14   
603-601 6 Hampton NH   318J COMCAST IP PHONE, LLC 122   2006-09-09   
603-601 7 Hampton NH   318J COMCAST IP PHONE, LLC 122   2011-06-03   
603-601 8 Hampton NH   318J COMCAST IP PHONE, LLC 122   2013-07-08   
603-601 9 Hampton NH   073H TELNYX LLC 122   2022-10-23   

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

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