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: 313

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-313 A Fork MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-313 1 Fork MD   145J TERRA NOVA TELECOM INC. 238   2025-05-07   
443-313 2 Fork MD   145J TERRA NOVA TELECOM INC. 238   2022-05-06   
443-313 3 Fork MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2015-03-19   
443-313 5 Fork MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-313 6 Fork MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-04   
443-313 7 Fork MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-04   
443-313 8 Fork MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-313 9 Fork MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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