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: 704

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-704 A Derry NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-704 0 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2022-07-02   
603-704 1 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-11-01   
603-704 2 Derry NH   637E ONVOY, LLC - NH 122   2022-01-15   
603-704 3 Derry NH   637E ONVOY, LLC - NH 122   2021-08-02   
603-704 4 Derry NH   637E ONVOY, LLC - NH 122   2021-08-02   
603-704 5 Derry NH   637E ONVOY, LLC - NH 122   2021-11-13   
603-704 6 Derry NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-04-25   
603-704 7 Derry NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-04-25   
603-704 8 Derry NH   637E ONVOY, LLC - NH 122   2022-05-20   
603-704 9 Derry NH   637E ONVOY, LLC - NH 122   2022-05-20   

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

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