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: 906

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-906 A Barnstead NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122      
603-906 2 Barnstead NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122   2009-12-18   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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