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: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-604 A Rye Beach NH RYBHNHCEPS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-604 0 Rye Beach NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-07-04   
603-604 4 Rye Beach NH RYBHNHCEPS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122   2024-09-13   
603-604 6 Rye Beach NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2019-06-20   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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