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: 405

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-405 A Somersworth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122      
603-405 0 Somersworth NH ROCHNHWE4MD  314C IDT AMERICA, CORP. - NH 122   2020-12-24   
603-405 1 Somersworth NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-07-04   
603-405 2 Somersworth NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122   2017-02-16   
603-405 6 Somersworth NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2016-06-17   
603-405 8 Somersworth NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2017-05-04   

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

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