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: 500

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-500 A Gaithersburg MD   824J OPENTACT INC. 236   2026-05-09   
227-500 0 Gaithersburg MD   824J OPENTACT INC. 236   2026-05-09   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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