Local Calling Guide

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

NXX: 316

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-316 A Milford NH MNCHNHACAMD  6386 BELL ATLANTIC MOBILE, INC 122      
603-316 0 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2017-11-30   
603-316 1 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2018-01-04   
603-316 2 Milford NH   637E ONVOY, LLC - NH 122   2021-08-02   
603-316 3 Milford NH   637E ONVOY, LLC - NH 122   2021-05-07   
603-316 4 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2018-10-05   
603-316 5 Milford NH   637E ONVOY, LLC - NH 122   2022-01-15   
603-316 6 Milford NH   637E ONVOY, LLC - NH 122   2021-08-02   
603-316 7 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2020-12-25   
603-316 8 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2019-05-18   
603-316 9 Milford NH   6386 BELL ATLANTIC MOBILE, INC 122   2021-08-24   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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