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: 551

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-551 A Woodlawn MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-551 0 Woodlawn MD   876D ONVOY, LLC - MD 238   2024-05-11   
443-551 1 Woodlawn MD   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-551 2 Woodlawn MD   876D ONVOY, LLC - MD 238   2024-07-05   
443-551 3 Woodlawn MD   318J COMCAST IP PHONE, LLC 238   2013-05-12   
443-551 4 Woodlawn MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-551 5 Woodlawn MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-08-11   
443-551 6 Woodlawn MD   876D ONVOY, LLC - MD 238   2025-02-01   
443-551 7 Woodlawn MD   876D ONVOY, LLC - MD 238   2025-02-01   
443-551 8 Woodlawn MD   876D ONVOY, LLC - MD 238   2024-10-21   
443-551 9 Woodlawn MD   876D ONVOY, LLC - MD 238   2024-10-21   

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

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