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: 317

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-317 A Lexington Park-Great Mills MD LNHMMDADGT0  8832 STARPOWER COMMUNICATIONS, LLC - MD 236      
240-317 0 Lexington Park-Great Mills MD LNHMMDADGT0  8832 STARPOWER COMMUNICATIONS, LLC - MD 236      
240-317 1 Lexington Park-Great Mills MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2026-07-13   
240-317 2 Lexington Park-Great Mills MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2008-02-13   
240-317 3 Lexington Park-Great Mills MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2008-02-13   
240-317 4 Lexington Park-Great Mills MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2007-10-22   
240-317 5 Lexington Park-Great Mills MD CHCHMDBEXCX  228C IDT AMERICA, CORP. - MD 236   2009-03-05   
240-317 6 Lexington Park-Great Mills MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2007-02-19   
240-317 7 Lexington Park-Great Mills MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-02-25   
240-317 8 Lexington Park-Great Mills MD LNHMMDADGT0  8832 STARPOWER COMMUNICATIONS, LLC - MD 236      
240-317 9 Lexington Park-Great Mills MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2008-12-13   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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