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: 338

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-338 A Keene NH MNCHNHACDS0  7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      
603-338 0 Keene NH   793K TWC IP ENABLED SERVICES, LLC 122   2015-09-14   
603-338 1 Keene NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2021-09-30   
603-338 2 Keene NH   073H TELNYX LLC 122   2022-10-08   
603-338 3 Keene NH   637E ONVOY, LLC - NH 122   2023-04-06   
603-338 4 Keene NH   9827 OTEL TELEKOM, INC. - NH 122   2002-09-19   
603-338 5 Keene NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2004-02-10   
603-338 6 Keene NH   637E ONVOY, LLC - NH 122   2022-11-26   
603-338 7 Keene NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2016-04-24   
603-338 8 Keene NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2015-02-28   
603-338 9 Keene NH   7778 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NH 122      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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