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: 406

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-406 A Concord NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-406 0 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2020-08-14   
603-406 1 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2020-01-13   
603-406 2 Concord NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122   2019-12-26   
603-406 3 Concord NH MNCHNHCOCM1  5562 METROPCS, INC. 122   2019-08-07   
603-406 4 Concord NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2019-03-26   
603-406 5 Concord NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2019-11-02   
603-406 6 Concord NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-04-04   
603-406 7 Concord NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-05-18   
603-406 8 Concord NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-02-05   
603-406 9 Concord NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2019-02-23   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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