Local Calling Guide

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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 291

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-291 A Hampstead MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-291 2 Hampstead MD   876D ONVOY, LLC - MD 238   2016-03-21   
443-291 3 Hampstead MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-09-09   
443-291 4 Hampstead MD   145J TERRA NOVA TELECOM INC. 238   2025-08-29   
443-291 5 Hampstead MD   876D ONVOY, LLC - MD 238   2024-03-08   
443-291 6 Hampstead MD   318J COMCAST IP PHONE, LLC 238   2005-07-20   
443-291 7 Hampstead MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-03-03   
443-291 8 Hampstead MD   876D ONVOY, LLC - MD 238   2016-03-21   
443-291 9 Hampstead MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   

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

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