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: 780

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-780 A Gaithersburg MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
240-780 0 Gaithersburg MD   515J IP HORIZON LLC 236   2013-09-07   
240-780 1 Gaithersburg MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2009-06-14   
240-780 2 Gaithersburg MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-11-29   
240-780 3 Gaithersburg MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
240-780 4 Gaithersburg MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
240-780 5 Gaithersburg MD   876D ONVOY, LLC - MD 236   2021-07-12   
240-780 6 Gaithersburg MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2009-06-14   
240-780 7 Gaithersburg MD   318J COMCAST IP PHONE, LLC 236   2012-10-07   
240-780 8 Gaithersburg MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2012-10-19   
240-780 9 Gaithersburg MD   939H COMMIO, LLC 236   2021-07-12   

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

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