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: 788

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-788 A Westminster MD BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238      
667-788 0 Westminster MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2021-12-16   
667-788 1 Westminster MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2021-12-16   
667-788 2 Westminster MD   876D ONVOY, LLC - MD 238   2021-12-19   
667-788 3 Westminster MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2022-06-07   
667-788 4 Westminster MD   490J DISH WIRELESS, LLC 238   2022-12-20   
667-788 6 Westminster MD   624H ONVOY SPECTRUM, LLC 238   2022-01-15   
667-788 7 Westminster MD   624H ONVOY SPECTRUM, LLC 238   2022-01-15   
667-788 8 Westminster MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2022-05-09   
667-788 9 Westminster MD   2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2021-12-06   

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

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