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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-421 A Columbia MD BLTMMDCHX7X  073H TELNYX LLC 238      
667-421 0 Columbia MD BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-01-21   
667-421 1 Columbia MD BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-04-26   
667-421 2 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-25   
667-421 3 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-25   
667-421 4 Columbia MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-421 5 Columbia MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-421 6 Columbia MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-421 7 Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-06-26   
667-421 8 Columbia MD BLTMMDCHX7X  073H TELNYX LLC 238   2023-04-24   
667-421 9 Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-06-26   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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