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: 992

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-992 A Danbury NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-992 2 Danbury NH   145J TERRA NOVA TELECOM INC. 122   2025-04-09   
603-992 4 Danbury NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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