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: 375

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-375 A Ashland NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122      
603-375 0 Ashland NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-07-22   
603-375 3 Ashland NH   637E ONVOY, LLC - NH 122   2025-02-02   
603-375 4 Ashland NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122   2012-10-02   

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

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