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: 830

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-830 A Catonsville MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-830 0 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-830 1 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-830 2 Catonsville MD   829J PAETEC ITEL, LLC 238      
443-830 3 Catonsville MD   876D ONVOY, LLC - MD 238   2021-09-23   
443-830 4 Catonsville MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2024-11-18   
443-830 5 Catonsville MD   876D ONVOY, LLC - MD 238   2021-07-11   
443-830 6 Catonsville MD   876D ONVOY, LLC - MD 238   2021-07-11   
443-830 7 Catonsville MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-10-10   
443-830 8 Catonsville MD   197D VONAGE AMERICA LLC 238   2022-10-07   
443-830 9 Catonsville MD   624H ONVOY SPECTRUM, LLC 238   2021-05-22   

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

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