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: 861

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-861 A Tamworth NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      
603-861 0 Tamworth NH MNCHNHAC7MD  145J TERRA NOVA TELECOM INC. 122   2024-06-27   
603-861 6 Tamworth NH   145J TERRA NOVA TELECOM INC. 122   2025-02-13   
603-861 9 Tamworth NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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