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 MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2022-06-05   
603-857 1 Suncook NH MNCHNHCO23Z  073H TELNYX LLC 122   2023-10-16   
603-857 7 Suncook NH MNCHNHCOX9Z  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 MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122   2024-09-28   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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