Local Calling Guide

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

NXX: 453

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-453 A Hampstead NH MNCHNHCO37Z  7421 AT&T - LOCAL 122      
603-453 0 Hampstead NH   6386 BELL ATLANTIC MOBILE, INC 122   2020-11-26   
603-453 1 Hampstead NH   073H TELNYX LLC 122   2022-12-02   
603-453 2 Hampstead NH   6386 BELL ATLANTIC MOBILE, INC 122   2023-05-28   
603-453 3 Hampstead NH   6386 BELL ATLANTIC MOBILE, INC 122   2024-03-08   
603-453 4 Hampstead NH   6386 BELL ATLANTIC MOBILE, INC 122   2024-10-08   
603-453 5 Hampstead NH   6386 BELL ATLANTIC MOBILE, INC 122   2025-02-20   
603-453 6 Hampstead NH   8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2021-07-07   
603-453 8 Hampstead NH   6386 BELL ATLANTIC MOBILE, INC 122   2023-12-04   
603-453 9 Hampstead NH   7421 AT&T - LOCAL 122   2021-07-07   

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

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