Local Calling Guide

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

NXX: 733

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-733 A Waterloo MD CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-733 0 Waterloo MD BLTMMDSN5MD  4773 XO MARYLAND, LLC 238   2003-02-16   
443-733 1 Waterloo MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238   2003-03-04   
443-733 2 Waterloo MD BLTMMDCH14Z  2697 CTC COMMUNICATIONS CORP. - MD 238   2009-03-17   
443-733 3 Waterloo MD BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-733 4 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-28   
443-733 5 Waterloo MD PIVLMDPKQMD  9170 BROADVIEW NETWORKS, INC. - MD 238   2013-10-10   
443-733 6 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-28   
443-733 7 Waterloo MD BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-733 8 Waterloo MD BLTMMDCHLMD  082H LOCAL ACCESS LLC - MD 238   2016-05-31   
443-733 9 Waterloo MD CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

Last updated: Fri, 13 May 2022 22:16:13 UTC

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