Local Calling Guide

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

NXX: 389

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-389 A Durham NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-389 0 Durham NH   829J PAETEC ITEL, LLC 122   2001-03-26   
603-389 1 Durham NH   829J PAETEC ITEL, LLC 122   2005-02-18   
603-389 2 Durham NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122   2007-07-23   
603-389 3 Durham NH PTMONH073MD  9827 OTEL TELEKOM, INC. - NH 122   2006-08-22   
603-389 4 Durham NH   829J PAETEC ITEL, LLC 122      
603-389 5 Durham NH   829J PAETEC ITEL, LLC 122      
603-389 6 Durham NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2010-09-27   
603-389 7 Durham NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2015-11-15   
603-389 8 Durham NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122   2008-04-18   
603-389 9 Durham NH   829J PAETEC ITEL, LLC 122   2000-09-01   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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