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: 840

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-840 A Catonsville MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-840 0 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-06-18   
443-840 1 Catonsville MD   9212 VERIZON MARYLAND, INC. 238   2008-07-10   
443-840 2 Catonsville MD   9212 VERIZON MARYLAND, INC. 238   2008-07-10   
443-840 3 Catonsville MD   9212 VERIZON MARYLAND, INC. 238   2008-07-10   
443-840 4 Catonsville MD   9212 VERIZON MARYLAND, INC. 238   2008-07-10   
443-840 5 Catonsville MD   9212 VERIZON MARYLAND, INC. 238   2008-07-10   
443-840 6 Catonsville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-840 7 Catonsville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-31   
443-840 8 Catonsville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-31   
443-840 9 Catonsville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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