Local Calling Guide

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

NXX: 461

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-461 A Merrimack NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-461 0 Merrimack NH   5562 METROPCS, INC. 122   2017-01-21   
603-461 1 Merrimack NH   5562 METROPCS, INC. 122   2008-12-15   
603-461 2 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      
603-461 3 Merrimack NH   637E ONVOY, LLC - NH 122   2023-07-10   
603-461 4 Merrimack NH   5562 METROPCS, INC. 122   2014-12-18   
603-461 5 Merrimack NH   637E ONVOY, LLC - NH 122   2023-05-08   
603-461 6 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      
603-461 8 Merrimack NH   637E ONVOY, LLC - NH 122   2023-08-20   
603-461 9 Merrimack NH   6386 BELL ATLANTIC MOBILE, INC 122   2023-12-08   

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

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