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: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-399 A Union Bridge MD BLTMMDCHXVX  321J HD CARRIER LLC 238      
667-399 0 Union Bridge MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-06-11   
667-399 1 Union Bridge MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-06-11   
667-399 4 Union Bridge MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-23   
667-399 5 Union Bridge MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-03-06   
667-399 6 Union Bridge MD BLTMMDCHX7X  073H TELNYX LLC 238   2022-09-09   
667-399 7 Union Bridge MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-03-06   
667-399 8 Union Bridge MD BLTMMDCHXVX  321J HD CARRIER LLC 238   2020-06-01   
667-399 9 Union Bridge MD BLTMMDCHXVX  321J HD CARRIER LLC 238   2020-06-01   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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