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: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-231 A Derry NH MNCHNHCOCM1  6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 0 Derry NH   5562 METROPCS, INC. 122      
603-231 1 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 2 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 3 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 4 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 5 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 6 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 7 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 8 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      
603-231 9 Derry NH   6889 OMNIPOINT MIAMI E LICENSE, LLC 122      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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