Local Calling Guide

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

NXX: 523

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-523 A Canaan NH CANNNHYARS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-523 2 Canaan NH   318J COMCAST IP PHONE, LLC 122   2007-01-30   
603-523 3 Canaan NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-523 4 Canaan NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-523 5 Canaan NH   145J TERRA NOVA TELECOM INC. 122   2022-10-06   
603-523 7 Canaan NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-523 8 Canaan NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-523 9 Canaan NH   5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      

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

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