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: 720

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-720 A Troy NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122      
603-720 1 Troy NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122   2023-05-21   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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