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: 678

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-678 A Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238      
667-678 0 Columbia MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-10-16   
667-678 1 Columbia MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-10-16   
667-678 2 Columbia MD   876D ONVOY, LLC - MD 238   2021-10-15   
667-678 3 Columbia MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-10-24   
667-678 4 Columbia MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-10-24   
667-678 5 Columbia MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-10-24   
667-678 6 Columbia MD   939H COMMIO, LLC 238   2021-10-16   
667-678 7 Columbia MD   939H COMMIO, LLC 238   2021-10-16   
667-678 8 Columbia MD   939H COMMIO, LLC 238   2021-10-16   
667-678 9 Columbia MD   939H COMMIO, LLC 238   2021-10-16   

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

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