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: 333

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-333 A Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2025-10-16   
227-333 0 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2025-10-17   
227-333 3 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2025-10-16   
227-333 4 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2025-10-16   
227-333 5 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2025-10-16   
227-333 6 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2025-10-16   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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