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: 614

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-614 A West Chesterfield NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-614 2 West Chesterfield NH   145J TERRA NOVA TELECOM INC. 122   2023-08-09   
603-614 3 West Chesterfield NH   829J PAETEC ITEL, LLC 122   2006-08-21   
603-614 4 West Chesterfield NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-614 5 West Chesterfield NH   637E ONVOY, LLC - NH 122   2023-07-06   
603-614 6 West Chesterfield NH   7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122   2018-08-12   
603-614 8 West Chesterfield NH   318J COMCAST IP PHONE, LLC 122   2007-01-12   

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

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