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: 344

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-344 A Suncook NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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