Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 240 [Rate centres in NPA 240] [Dial plan for NPA 240]

NXX: 388

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-388 A Gaithersburg MD BTVLMD12CMA  5562 METROPCS, INC. 236      
240-388 0 Gaithersburg MD   5562 METROPCS, INC. 236   2003-05-14   
240-388 1 Gaithersburg MD   5562 METROPCS, INC. 236   2003-05-14   
240-388 2 Gaithersburg MD   5562 METROPCS, INC. 236   2003-08-17   
240-388 3 Gaithersburg MD   5562 METROPCS, INC. 236   2004-05-13   
240-388 4 Gaithersburg MD   5562 METROPCS, INC. 236   2004-05-13   
240-388 5 Gaithersburg MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2007-12-03   
240-388 6 Gaithersburg MD   5562 METROPCS, INC. 236   2002-12-24   
240-388 7 Gaithersburg MD   5562 METROPCS, INC. 236   2003-02-26   
240-388 8 Gaithersburg MD   5562 METROPCS, INC. 236   2003-02-26   
240-388 9 Gaithersburg MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2004-11-21   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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