Local Calling Guide

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

NXX: 637

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-637 A Armiger-Gibson Island MD BLTMMDSN5MD  4773 XO MARYLAND, LLC 238      
443-637 0 Armiger-Gibson Island MD BLTMMDSN5MD  4773 XO MARYLAND, LLC 238      
443-637 1 Armiger-Gibson Island MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-01-10   
443-637 2 Armiger-Gibson Island MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-11-29   
443-637 3 Armiger-Gibson Island MD BLTMMDSN5MD  4773 XO MARYLAND, LLC 238      
443-637 4 Armiger-Gibson Island MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-637 5 Armiger-Gibson Island MD BLTMMDSN5MD  4773 XO MARYLAND, LLC 238      
443-637 6 Armiger-Gibson Island MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-07   
443-637 7 Armiger-Gibson Island MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2012-10-11   
443-637 8 Armiger-Gibson Island MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2012-10-11   
443-637 9 Armiger-Gibson Island MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2012-10-11   

Last updated: Wed, 12 Jan 2022 16:20:07 UTC

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