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: 590

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-590 A Durham NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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