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: 900

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-900 A Washington Zone 15 MD   876D ONVOY, LLC - MD 236   2026-12-06   
227-900 0 Washington Zone 15 MD   876D ONVOY, LLC - MD 236   2026-12-06   

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

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