Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 227 [Rate centres in NPA 227] [Dial plan for NPA 227]

NXX: 324

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-324 A Gaithersburg MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-11-27   
227-324 9 Gaithersburg MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-11-27   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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