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: 284

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-284 A Waterloo MD BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-284 2 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-284 3 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-284 5 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-284 6 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-284 7 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-23   

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

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