Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Grantsville, MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
227-209 A HGTWMD539MD  939H COMMIO, LLC 240      
227-209 0   939H COMMIO, LLC 240   2023-11-04   
227-209 1   939H COMMIO, LLC 240   2023-11-04   
227-209 2   939H COMMIO, LLC 240   2023-11-04   
227-209 3   939H COMMIO, LLC 240   2023-11-04   
227-209 4   939H COMMIO, LLC 240   2023-11-04   
227-209 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2025-08-11   
240-275 A HGTWMD53DS0  2593 CORE COMMUNICATIONS, INC.- MD 240      
240-588 A FRDRMDFRXVX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 240      
240-588 0   2593 CORE COMMUNICATIONS, INC.- MD 240   2018-07-07   
240-588 1   2593 CORE COMMUNICATIONS, INC.- MD 240   2018-07-07   
240-588 2   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-04-15   
240-588 3   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 240   2018-05-01   
240-588 4   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-31   
240-588 5   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-31   
240-588 6   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-31   
240-588 7   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-31   
240-588 8   2593 CORE COMMUNICATIONS, INC.- MD 240   2018-07-07   
240-588 9   5562 METROPCS, INC. 240   2019-04-04   
240-692 A FRDRMDFRXMD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 240      
240-692 0   073H TELNYX LLC 240   2021-03-04   
240-692 1   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 240   2019-07-21   
240-692 2   876D ONVOY, LLC - MD 240   2020-01-06   
240-692 3   876D ONVOY, LLC - MD 240   2020-01-06   
240-692 4   876D ONVOY, LLC - MD 240   2021-03-04   
240-692 5   624H ONVOY SPECTRUM, LLC 240   2021-05-24   
240-692 6   876D ONVOY, LLC - MD 240   2023-06-16   
240-692 7   624H ONVOY SPECTRUM, LLC 240   2021-11-15   
240-692 8   624H ONVOY SPECTRUM, LLC 240   2021-11-15   
301-895 A GTVLMDGRRS0  9212 VERIZON MARYLAND, INC. 240      
301-895 0   071F BANDWIDTH.COM CLEC, LLC - MD 240   2012-02-06   
301-895 1   073H TELNYX LLC 240   2017-08-08   
301-895 2   071F BANDWIDTH.COM CLEC, LLC - MD 240   2015-06-20   
301-895 3   9212 VERIZON MARYLAND, INC. 240      
301-895 4   9212 VERIZON MARYLAND, INC. 240      
301-895 5   9212 VERIZON MARYLAND, INC. 240      
301-895 6   508J CENTURYLINK COMMUNICATIONS, LLC 240   2016-11-12   
301-895 7   876D ONVOY, LLC - MD 240   2016-09-12   
301-895 8   318J COMCAST IP PHONE, LLC 240   2010-03-05   
301-895 9   876D ONVOY, LLC - MD 240   2016-09-12   

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

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