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: 502

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
603-502 A Portsmouth NH DRRYNHBC1MD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 122      

Last updated: Sat, 02 May 2026 12:20:53 UTC

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