Local Calling Guide

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

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-257 A Plaistow NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-257 0 Plaistow NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2016-11-16   
603-257 1 Plaistow NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122      
603-257 2 Plaistow NH MNCHNHCO23Z  073H TELNYX LLC 122   2023-03-20   
603-257 5 Plaistow NH   829J PAETEC ITEL, LLC 122   2010-08-10   
603-257 6 Plaistow NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-05-16   
603-257 7 Plaistow NH   829J PAETEC ITEL, LLC 122   2007-05-04   
603-257 9 Plaistow NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122      

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

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