Local Calling Guide

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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 556

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-556 A Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 0 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 1 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 2 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 3 Gaithersburg MD BTVLMD12CMA  5562 METROPCS, INC. 236   2004-11-18   
301-556 4 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 5 Gaithersburg MD LARLMDCCDS0  4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 236   2004-05-06   
301-556 6 Gaithersburg MD BTVLMD12CMA  5562 METROPCS, INC. 236   2004-02-28   
301-556 7 Gaithersburg MD BTVLMD12CMA  5562 METROPCS, INC. 236   2004-02-28   
301-556 8 Gaithersburg MD BTVLMD12CMA  5562 METROPCS, INC. 236   2005-11-13   
301-556 9 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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