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: 529

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
227-529 A Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-02-20   
227-529 0 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-02-20   
227-529 1 Gaithersburg MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2026-02-27   
227-529 2 Gaithersburg MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2026-02-27   
227-529 3 Gaithersburg MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2026-02-27   
227-529 4 Gaithersburg MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2026-02-27   
227-529 9 Gaithersburg MD   876D ONVOY, LLC - MD 236   2026-02-20   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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