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: 670

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-670 A Catonsville MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-670 0 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-670 1 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-670 2 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-03-19   
443-670 3 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-670 4 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-03-19   
443-670 5 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-670 6 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-03-19   
443-670 7 Catonsville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-03-19   
443-670 8 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-670 9 Catonsville MD   829J PAETEC ITEL, LLC 238      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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