Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 820

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-820 A Merrimack NH MNCHNHCOCM1  5562 METROPCS, INC. 122      
603-820 0 Merrimack NH   5562 METROPCS, INC. 122   2008-05-12   
603-820 1 Merrimack NH   5562 METROPCS, INC. 122   2010-02-28   
603-820 2 Merrimack NH   5562 METROPCS, INC. 122   2010-02-28   
603-820 3 Merrimack NH   5562 METROPCS, INC. 122   2010-02-28   
603-820 4 Merrimack NH   5562 METROPCS, INC. 122   2010-10-23   
603-820 5 Merrimack NH   5562 METROPCS, INC. 122   2010-10-23   
603-820 6 Merrimack NH   5562 METROPCS, INC. 122   2010-10-23   
603-820 7 Merrimack NH   5562 METROPCS, INC. 122   2012-01-21   
603-820 8 Merrimack NH   8468 FREEDOM RING COMMUNICATIONS, LLC 122   2008-09-10   
603-820 9 Merrimack NH   5562 METROPCS, INC. 122   2014-11-06   

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

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