Local Calling Guide

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

NXX: 346

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-346 A Plymouth NH MNCHNHAC9MD  321J HD CARRIER LLC 122      
603-346 0 Plymouth NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2016-01-26   
603-346 1 Plymouth NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2016-01-26   
603-346 2 Plymouth NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122   2018-06-23   
603-346 4 Plymouth NH MNCHNHCOX8Z  4017 LEVEL 3 COMMUNICATIONS, LLC - NH 122      
603-346 8 Plymouth NH MNCHNHCO23Z  073H TELNYX LLC 122   2024-07-04   
603-346 9 Plymouth NH MNCHNHAC9MD  321J HD CARRIER LLC 122   2022-04-01   

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

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