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: 607

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-607 A West Chesterfield NH DOVRNHTHXJX  478J NUSO, LLC 122      
603-607 1 West Chesterfield NH DOVRNHTHXJX  478J NUSO, LLC 122   2020-10-11   
603-607 2 West Chesterfield NH DOVRNHTHXEX  8299 TELEPORT COMMUNICATIONS AMERICA, LLC - NH 122   2023-11-13   
603-607 5 West Chesterfield NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2022-12-23   
603-607 6 West Chesterfield NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2021-05-23   
603-607 7 West Chesterfield NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2021-08-02   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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