Local Calling Guide

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NPA: 603 [Rate centres in NPA 603] [Dial plan for NPA 603]

NXX: 256

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-256 A West Chesterfield NH BRBOVTMADS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-256 1 West Chesterfield NH MNCHNHCO42Z  793K TWC IP ENABLED SERVICES, LLC 122   2024-01-07   
603-256 2 West Chesterfield NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2023-03-30   
603-256 3 West Chesterfield NH BRBOVTMADS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-256 4 West Chesterfield NH BRBOVTMADS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-256 5 West Chesterfield NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2022-01-15   
603-256 6 West Chesterfield NH BRBOVTMADS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-256 7 West Chesterfield NH PTMONH073MD  8468 FREEDOM RING COMMUNICATIONS, LLC 122   2001-02-06   
603-256 8 West Chesterfield NH BRBOVTMADS0  5113 CONSOLIDATED COMM OF NO. NEW ENGLAND-NH 122      
603-256 9 West Chesterfield NH MNCHNHCOX9Z  637E ONVOY, LLC - NH 122   2023-09-28   

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

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