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: 283

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-283 A Fork MD BLTMMDCHXAX  7421 AT&T - LOCAL 238      
667-283 0 Fork MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-01-08   
667-283 1 Fork MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-04-09   
667-283 2 Fork MD   876D ONVOY, LLC - MD 238   2023-08-10   
667-283 3 Fork MD   876D ONVOY, LLC - MD 238   2021-07-11   
667-283 4 Fork MD   876D ONVOY, LLC - MD 238   2021-07-11   
667-283 5 Fork MD   516J TON80 COMMUNICATIONS, LLC 238   2022-03-29   
667-283 6 Fork MD   624H ONVOY SPECTRUM, LLC 238   2022-01-20   
667-283 7 Fork MD   624H ONVOY SPECTRUM, LLC 238   2022-01-20   
667-283 8 Fork MD   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2021-02-26   
667-283 9 Fork MD   7421 AT&T - LOCAL 238   2020-08-24   

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

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