Local Calling Guide

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

NXX: 261

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-261 A Merrimack NH MNCHNHCOX4Z  6290 UNITED STATES CELLULAR - NH 122      
603-261 0 Merrimack NH   5562 METROPCS, INC. 122   2008-12-15   
603-261 1 Merrimack NH   5562 METROPCS, INC. 122   2008-12-15   
603-261 2 Merrimack NH   4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122   2010-09-27   
603-261 3 Merrimack NH   318J COMCAST IP PHONE, LLC 122   2013-11-20   
603-261 4 Merrimack NH   5562 METROPCS, INC. 122   2014-11-06   
603-261 5 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      
603-261 6 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      
603-261 7 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      
603-261 8 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      
603-261 9 Merrimack NH   6290 UNITED STATES CELLULAR - NH 122      

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

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