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: 780

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-780 A Canaan NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-780 4 Canaan NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      

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

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