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: 874

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-874 A Monroe NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-874 1 Monroe NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2005-09-15   
603-874 4 Monroe NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      

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

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