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: 951

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-951 A Annapolis MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-951 0 Annapolis MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-951 1 Annapolis MD   145J TERRA NOVA TELECOM INC. 238   2024-12-29   
443-951 2 Annapolis MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-951 3 Annapolis MD   876D ONVOY, LLC - MD 238   2014-10-25   
443-951 4 Annapolis MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-951 5 Annapolis MD   281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-27   
443-951 6 Annapolis MD   073H TELNYX LLC 238   2022-12-26   
443-951 7 Annapolis MD   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238   2014-11-12   
443-951 8 Annapolis MD   281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-27   
443-951 9 Annapolis MD   281E YMAX COMMUNICATIONS CORP. - MD 238   2007-08-20   

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

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