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: 238

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-238 A Washington Zone 14 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2024-06-20   
227-238 0 Washington Zone 14 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-12   
227-238 1 Washington Zone 14 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-12   
227-238 2 Washington Zone 14 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-12   
227-238 7 Washington Zone 14 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-11-04   
227-238 8 Washington Zone 14 MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2024-11-02   
227-238 9 Washington Zone 14 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2024-06-20   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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