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: 571

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-571 A Derry NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2024-01-05   
603-571 0 Derry NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122      
603-571 1 Derry NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122      
603-571 2 Derry NH   145J TERRA NOVA TELECOM INC. 122   2024-02-02   
603-571 3 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2025-09-06   
603-571 4 Derry NH   073H TELNYX LLC 122   2024-01-15   
603-571 5 Derry NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122      
603-571 6 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2025-12-26   
603-571 7 Derry NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122      
603-571 8 Derry NH   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122      
603-571 9 Derry NH   6386 BELL ATLANTIC MOBILE, INC 122   2025-04-23   

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

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