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: 612

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-612 A Plaistow NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-612 0 Plaistow NH   829J PAETEC ITEL, LLC 122   2000-05-24   
603-612 1 Plaistow NH   829J PAETEC ITEL, LLC 122   2002-07-24   
603-612 4 Plaistow NH PTMONH073MD  9827 OTEL TELEKOM, INC. - NH 122   2002-09-20   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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