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: 280

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-280 A Barrington NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-280 0 Barrington NH MNCHNHAC7MD  145J TERRA NOVA TELECOM INC. 122   2024-06-26   
603-280 1 Barrington NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-06-30   
603-280 4 Barrington NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-280 6 Barrington NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2020-04-27   

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

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