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: 338

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-338 A Washington Zone 10 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-12-04   
227-338 9 Washington Zone 10 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-12-04   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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