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: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-310 A Parkville MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
667-310 0 Parkville MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-07-30   
667-310 1 Parkville MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2021-10-17   
667-310 2 Parkville MD   876D ONVOY, LLC - MD 238   2021-09-23   
667-310 3 Parkville MD   624H ONVOY SPECTRUM, LLC 238   2021-05-29   
667-310 4 Parkville MD   939H COMMIO, LLC 238   2021-08-28   
667-310 5 Parkville MD   939H COMMIO, LLC 238   2021-08-28   
667-310 6 Parkville MD   939H COMMIO, LLC 238   2021-08-28   
667-310 7 Parkville MD   939H COMMIO, LLC 238   2021-08-28   
667-310 8 Parkville MD   939H COMMIO, LLC 238   2021-08-28   
667-310 9 Parkville MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-05-28   

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

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