Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 636

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-636 A Catonsville MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238      
443-636 0 Catonsville MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2008-03-31   
443-636 1 Catonsville MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2007-05-30   
443-636 2 Catonsville MD BLTMMDCHW29  4716 PAETEC COMMUNICATIONS, INC. - MD 238   2006-02-12   
443-636 3 Catonsville MD BLTMMDCH14Z  2697 CTC COMMUNICATIONS CORP. - MD 238   2006-02-25   
443-636 4 Catonsville MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-636 5 Catonsville MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2007-08-13   
443-636 6 Catonsville MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-08-20   
443-636 7 Catonsville MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2008-07-17   
443-636 8 Catonsville MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-27   
443-636 9 Catonsville MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-27   

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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