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: 407

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-407 A Belmont NH MNCHNHCOXAZ  4206 PAETEC COMMUNICATIONS, INC. - NH 122      
603-407 0 Belmont NH MNCHNHAC3MD  939H COMMIO, LLC 122   2022-11-05   
603-407 1 Belmont NH MNCHNHCOXAZ  4206 PAETEC COMMUNICATIONS, INC. - NH 122   2015-07-04   
603-407 8 Belmont NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-06-30   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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