Local Calling Guide

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

NXX: 542

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-542 A Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2021-01-13   
443-542 0 Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238      
443-542 1 Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2004-11-25   
443-542 2 Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238      
443-542 3 Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2005-03-12   
443-542 4 Columbia MD CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238   2004-12-20   
443-542 5 Columbia MD HNVAMDBHAMD  3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238   2004-06-25   
443-542 6 Columbia MD CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238   2004-12-20   
443-542 7 Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-02-02   
443-542 8 Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-09-01   
443-542 9 Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2007-01-19   

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

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