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: 404

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-404 A Derry NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122      
603-404 0 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2016-03-04   
603-404 1 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2016-12-10   
603-404 2 Derry NH   318J COMCAST IP PHONE, LLC 122   2016-06-15   
603-404 3 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2017-11-16   
603-404 4 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2017-07-07   
603-404 5 Derry NH   637E ONVOY, LLC - NH 122   2021-04-23   
603-404 6 Derry NH   318J COMCAST IP PHONE, LLC 122   2018-10-26   
603-404 7 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2024-04-23   
603-404 8 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2018-08-10   
603-404 9 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-07-30   

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

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