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: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-303 A Washington Zone 10 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-12-18   
227-303 0 Washington Zone 10 MD   876D ONVOY, LLC - MD 236   2025-12-19   
227-303 8 Washington Zone 10 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-12-18   
227-303 9 Washington Zone 10 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-12-18   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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