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: 270

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-270 A Mount Airy MD   7421 AT&T - LOCAL 240   2025-03-08   
227-270 9 Mount Airy MD   7421 AT&T - LOCAL 240   2025-03-08   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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