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: 951

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-951 A Milan NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-951 0 Milan NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2022-07-01   
603-951 4 Milan NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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