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: 670

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-670 A Merrimack NH   829J PAETEC ITEL, LLC 122   2025-04-30   
603-670 0 Merrimack NH   829J PAETEC ITEL, LLC 122      
603-670 1 Merrimack NH   829J PAETEC ITEL, LLC 122      
603-670 2 Merrimack NH   829J PAETEC ITEL, LLC 122      
603-670 3 Merrimack NH MNCHNHCOCM1  5562 METROPCS, INC. 122   2003-10-12   
603-670 4 Merrimack NH MNCHNHCOCM1  5562 METROPCS, INC. 122   2003-10-12   
603-670 5 Merrimack NH MNCHNHCOCM1  5562 METROPCS, INC. 122   2003-12-29   
603-670 6 Merrimack NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2018-09-20   
603-670 7 Merrimack NH   829J PAETEC ITEL, LLC 122      
603-670 8 Merrimack NH MNCHNHCOCM1  5562 METROPCS, INC. 122   2004-01-10   
603-670 9 Merrimack NH   829J PAETEC ITEL, LLC 122      

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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