Local Calling Guide

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

NXX: 238

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-238 A Plymouth NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-238 0 Plymouth NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122   2008-04-18   
603-238 2 Plymouth NH   829J PAETEC ITEL, LLC 122      
603-238 3 Plymouth NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2006-10-30   
603-238 4 Plymouth NH PTMONH073MD  9827 OTEL TELEKOM, INC. - NH 122   2002-09-19   
603-238 5 Plymouth NH PTMONH073MD  9827 OTEL TELEKOM, INC. - NH 122   2004-10-09   
603-238 6 Plymouth NH   829J PAETEC ITEL, LLC 122      
603-238 7 Plymouth NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2009-01-05   
603-238 8 Plymouth NH MNCHNHCOCM1  5562 METROPCS, INC. 122   2005-07-16   
603-238 9 Plymouth NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122   2012-10-02   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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