Local Calling Guide

Area code/prefix search

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

NXX: 899

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-899 A Waterloo MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-899 0 Waterloo MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-11-26   
443-899 1 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-05-21   
443-899 2 Waterloo MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-06-26   
443-899 3 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-12   
443-899 4 Waterloo MD BLTMMDCHX7X  073H TELNYX LLC 238   2017-04-26   
443-899 5 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-899 6 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-899 7 Waterloo MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-899 8 Waterloo MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-899 9 Waterloo MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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