Local Calling Guide

Area code/prefix search

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

NXX: 273

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-273 A Laconia NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      
603-273 0 Laconia NH   829J PAETEC ITEL, LLC 122   2000-05-24   
603-273 1 Laconia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2015-05-06   
603-273 2 Laconia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2013-02-01   
603-273 3 Laconia NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2026-02-10   
603-273 4 Laconia NH PTMONH073MD  9827 OTEL TELEKOM, INC. - NH 122   2002-09-19   
603-273 5 Laconia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2021-06-18   
603-273 6 Laconia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2013-12-28   
603-273 7 Laconia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2013-04-01   
603-273 8 Laconia NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2015-09-01   
603-273 9 Laconia NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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