Local Calling Guide

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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 550

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-550 A North Beach MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-550 0 North Beach MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2025-01-19   
443-550 1 North Beach MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-10-14   
443-550 2 North Beach MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238   2004-02-05   
443-550 3 North Beach MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-550 4 North Beach MD BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2003-12-25   
443-550 5 North Beach MD PIVLMDPKFMD  9170 BROADVIEW NETWORKS, INC. - MD 238   2008-01-03   
443-550 6 North Beach MD NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238   2004-10-01   
443-550 7 North Beach MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-07   
443-550 8 North Beach MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2004-02-07   
443-550 9 North Beach MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-07-15   

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

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