Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 667 [Rate centres in NPA 667] [Dial plan for NPA 667]

NXX: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-400 A Baltimore MD BLTQMD012MD  964H BARR TELL USA, INC. 238      
667-400 0 Baltimore MD   876D ONVOY, LLC - MD 238   2017-10-15   
667-400 1 Baltimore MD   964H BARR TELL USA, INC. 238   2017-01-08   
667-400 2 Baltimore MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2017-03-02   
667-400 3 Baltimore MD   876D ONVOY, LLC - MD 238   2017-09-17   
667-400 4 Baltimore MD   876D ONVOY, LLC - MD 238   2017-09-17   
667-400 5 Baltimore MD   876D ONVOY, LLC - MD 238   2017-09-17   
667-400 6 Baltimore MD   876D ONVOY, LLC - MD 238   2017-09-17   
667-400 7 Baltimore MD   876D ONVOY, LLC - MD 238   2017-09-17   
667-400 8 Baltimore MD   551G NUSO, LLC 238   2018-11-07   
667-400 9 Baltimore MD   551G NUSO, LLC 238   2018-11-07   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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