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: 315

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-315 A Catonsville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-315 0 Catonsville MD   145J TERRA NOVA TELECOM INC. 238   2025-05-28   
443-315 1 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2026-10-16   
443-315 2 Catonsville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2013-08-01   
443-315 3 Catonsville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-02-05   
443-315 4 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2026-10-16   
443-315 5 Catonsville MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2012-05-26   
443-315 6 Catonsville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-02-05   
443-315 7 Catonsville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-02-05   
443-315 8 Catonsville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-02-05   
443-315 9 Catonsville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-02-05   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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