Local Calling Guide

Area code/prefix search

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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 251

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-251 A Charlestown NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-251 0 Charlestown NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-07-27   
603-251 1 Charlestown NH   829J PAETEC ITEL, LLC 122   2012-04-27   

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

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