Local Calling Guide

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

NXX: 508

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-508 A Pelham NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122      
603-508 0 Pelham NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-508 1 Pelham NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-508 2 Pelham NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122   2003-03-11   
603-508 3 Pelham NH   829J PAETEC ITEL, LLC 122   2003-06-04   
603-508 4 Pelham NH   6386 BELL ATLANTIC MOBILE, INC 122   2016-03-27   
603-508 5 Pelham NH   5562 METROPCS, INC. 122   2011-10-27   
603-508 6 Pelham NH   318J COMCAST IP PHONE, LLC 122   2006-10-31   
603-508 7 Pelham NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-508 8 Pelham NH   6386 BELL ATLANTIC MOBILE, INC 122      
603-508 9 Pelham NH   6386 BELL ATLANTIC MOBILE, INC 122      

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

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