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: 975

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-975 A Boscawen NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122      
603-975 0 Boscawen NH MNCHNHIE6MD  318J COMCAST IP PHONE, LLC 122   2010-01-25   
603-975 7 Boscawen NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2025-12-12   

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

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