Local Calling Guide

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

NXX: 383

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-383 A Jackson NH JCSNNHTHRS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-383 0 Jackson NH JCSNNHTHRS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-383 1 Jackson NH MNCHNHCO47Z  829J PAETEC ITEL, LLC 122   2000-05-24   
603-383 2 Jackson NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122   2015-05-01   
603-383 3 Jackson NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122   2012-10-02   
603-383 4 Jackson NH JCSNNHTHRS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-383 5 Jackson NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2004-09-04   
603-383 6 Jackson NH JCSNNHTHRS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-383 7 Jackson NH   145J TERRA NOVA TELECOM INC. 122   2023-11-16   
603-383 8 Jackson NH JCSNNHTHRS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-383 9 Jackson NH JCSNNHTHRS1  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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