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: 500

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-500 A Gaithersburg MD WASHDC12X6X  824J OPENTACT INC. 236   2026-05-09   
227-500 0 Gaithersburg MD WASHDC12X6X  824J OPENTACT INC. 236   2026-05-09   
227-500 1 Gaithersburg MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2026-05-11   
227-500 2 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-08-20   
227-500 3 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-08-20   
227-500 4 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-08-20   
227-500 5 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-08-20   
227-500 6 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-08-31   
227-500 7 Gaithersburg MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2026-09-06   
227-500 8 Gaithersburg MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2026-07-07   
227-500 9 Gaithersburg MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2026-05-30   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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