Local Calling Guide

Area code/prefix search

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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 770

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-770 A Danbury CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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