Local Calling Guide

Area code/prefix search

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

NXX: 872

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-872 A Gilmanton Iron Works NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122      
603-872 2 Gilmanton Iron Works NH   314C IDT AMERICA, CORP. - NH 122   2009-12-18   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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