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: 779

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-779 A Plymouth NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      
603-779 0 Plymouth NH   829J PAETEC ITEL, LLC 122   2001-06-06   
603-779 1 Plymouth NH   145J TERRA NOVA TELECOM INC. 122   2023-01-12   
603-779 3 Plymouth NH   145J TERRA NOVA TELECOM INC. 122   2023-08-06   
603-779 5 Plymouth NH   829J PAETEC ITEL, LLC 122   2004-08-23   
603-779 6 Plymouth NH   145J TERRA NOVA TELECOM INC. 122   2025-07-25   
603-779 9 Plymouth NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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