Local Calling Guide

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

NXX: 554

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-554 A Milford NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-554 0 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2012-12-19   
603-554 1 Milford NH   318J COMCAST IP PHONE, LLC 122   2008-09-16   
603-554 2 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2011-05-17   
603-554 3 Milford NH   637E ONVOY, LLC - NH 122   2023-07-06   
603-554 4 Milford NH   6290 UNITED STATES CELLULAR - NH 122      
603-554 5 Milford NH   6290 UNITED STATES CELLULAR - NH 122      
603-554 6 Milford NH   6290 UNITED STATES CELLULAR - NH 122      
603-554 7 Milford NH   6290 UNITED STATES CELLULAR - NH 122      
603-554 8 Milford NH   318J COMCAST IP PHONE, LLC 122   2011-06-27   
603-554 9 Milford NH   829J PAETEC ITEL, LLC 122   2012-05-18   

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

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