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: 516

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-516 A Sykesville MD   876D ONVOY, LLC - MD 238      
443-516 2 Sykesville MD   829J PAETEC ITEL, LLC 238   2004-12-22   
443-516 3 Sykesville MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
443-516 5 Sykesville MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2024-03-22   
443-516 6 Sykesville MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-09-19   
443-516 7 Sykesville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-06-02   
443-516 8 Sykesville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-28   
443-516 9 Sykesville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-28   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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