Local Calling Guide

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

NXX: 450

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-450 A Concord NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-450 0 Concord NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-06-05   
603-450 1 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 2 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 3 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 4 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 5 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 6 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 7 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 8 Concord NH   197D VONAGE AMERICA LLC 122   2018-12-06   
603-450 9 Concord NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2018-11-11   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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