Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 2596 QUANTUM TELECOMMUNICATIONS, INC. - MD

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
301-278 0 Washington Zone 5 MD LARLMDLR3MD  236   2003-12-25   
301-525 A Gaithersburg MD LARLMDLR3MD  236      
301-525 0 Gaithersburg MD LARLMDLR3MD  236   2003-12-07   
301-685 8 Damascus MD LARLMDLR3MD  236   2003-12-25   
301-769 0 Leonardtown MD LARLMDLR3MD  236   2003-12-25   
301-803 5 Washington Zone 2 MD LARLMDLR3MD  236   2003-12-25   
301-885 4 Waldorf MD LARLMDLR3MD  236   2003-12-25   
301-994 5 Lexington Park-Great Mills MD LARLMDLR3MD  236   2003-12-25   
410-346 4 Silver Run MD BLTMMD91DS2  238   2003-12-25   
410-441 7 Elkton MD BLTMMD91DS2  238   2003-12-25   
410-452 4 Cardiff MD BLTMMD91DS2  238   2003-12-25   
410-525 7 Baltimore MD BLTMMD91DS2  238   2016-01-31   
410-696 6 Ellicott City MD BLTMMD91DS2  238   2016-01-19   
410-773 0 Cockeysville MD BLTMMD91DS2  238   2003-12-25   
410-776 0 Bel Air MD BLTMMD91DS2  238   2003-12-25   
410-871 4 Westminster MD BLTMMD91DS2  238   2003-12-17   
410-940 0 Annapolis MD BLTMMD91DS2  238   2003-12-25   
410-946 0 Severna Park MD BLTMMD91DS2  238   2003-12-25   
410-970 8 Sykesville MD BLTMMD91DS2  238   2003-12-25   
410-982 A Baltimore MD BLTMMD91DS2  238      
410-982 0 Baltimore MD BLTMMD91DS2  238   2003-12-04   
443-507 4 Hampstead MD BLTMMD91DS2  238   2016-01-31   
443-550 4 North Beach MD BLTMMD91DS2  238   2003-12-25   
443-583 2 Columbia MD BLTMMD91DS2  238   2016-01-31   
667-755 A Pikesville MD BLTMMDCHX3Y  238      
667-755 5 Pikesville MD BLTMMDCHX3Y  238   2021-11-29   
667-788 A Westminster MD BLTMMD91DS2  238      
667-788 9 Westminster MD BLTMMDCHX3Y  238   2021-12-06   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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