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: 857

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-857 A Suncook NH   616J LEAP TELECOM, LLC 122      
603-857 0 Suncook NH   6386 BELL ATLANTIC MOBILE, INC 122   2022-06-05   
603-857 1 Suncook NH   073H TELNYX LLC 122   2023-10-16   
603-857 2 Suncook NH   6386 BELL ATLANTIC MOBILE, INC 122   2026-01-15   
603-857 7 Suncook NH   637E ONVOY, LLC - NH 122   2024-11-17   
603-857 8 Suncook NH   616J LEAP TELECOM, LLC 122   2025-05-04   
603-857 9 Suncook NH   6386 BELL ATLANTIC MOBILE, INC 122   2024-09-28   

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

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