Local Calling Guide

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Mount Airy, MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
227-270 A   7421 AT&T - LOCAL 240   2025-03-08   
227-270 0   145J TERRA NOVA TELECOM INC. 240   2025-03-10   
227-270 9   7421 AT&T - LOCAL 240   2025-03-08   
240-369 A HGTWMD53DS0  2593 CORE COMMUNICATIONS, INC.- MD 240      
240-394 A MNRVMDMOXFX  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240      
240-394 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2005-02-03   
240-394 1   071F BANDWIDTH.COM CLEC, LLC - MD 240   2010-02-22   
240-394 2   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2005-02-03   
240-394 3   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 240   2010-02-01   
240-394 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 240   2008-03-13   
240-394 5   071F BANDWIDTH.COM CLEC, LLC - MD 240   2010-08-08   
240-394 6   071F BANDWIDTH.COM CLEC, LLC - MD 240   2011-07-31   
240-394 7   071F BANDWIDTH.COM CLEC, LLC - MD 240   2011-08-17   
240-394 8   071F BANDWIDTH.COM CLEC, LLC - MD 240   2011-09-02   
240-394 9   071F BANDWIDTH.COM CLEC, LLC - MD 240   2008-12-04   
240-732 A MNRVMDMOXFX  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240      
240-732 0   071F BANDWIDTH.COM CLEC, LLC - MD 240   2016-09-19   
240-732 1   876D ONVOY, LLC - MD 240   2016-09-12   
240-732 2   876D ONVOY, LLC - MD 240   2016-09-12   
240-732 3   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2018-04-02   
240-732 4   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-29   
240-732 5   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-29   
240-732 6   2593 CORE COMMUNICATIONS, INC.- MD 240   2019-03-29   
240-732 7   508J CENTURYLINK COMMUNICATIONS, LLC 240   2016-10-27   
240-732 8   073H TELNYX LLC 240   2017-08-08   
240-732 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2016-01-11   
240-875 A CMLDMDCMEMD  876D ONVOY, LLC - MD 240      
240-875 0   071F BANDWIDTH.COM CLEC, LLC - MD 240   2021-11-22   
240-875 1   071F BANDWIDTH.COM CLEC, LLC - MD 240   2021-11-22   
240-875 2   624H ONVOY SPECTRUM, LLC 240   2021-05-24   
240-875 3   624H ONVOY SPECTRUM, LLC 240   2022-01-16   
240-875 4   876D ONVOY, LLC - MD 240   2024-03-02   
240-875 5   876D ONVOY, LLC - MD 240   2021-03-04   
240-875 6   876D ONVOY, LLC - MD 240   2021-03-04   
240-875 7   876D ONVOY, LLC - MD 240   2019-12-11   
240-875 8   876D ONVOY, LLC - MD 240   2019-12-11   
240-875 9   624H ONVOY SPECTRUM, LLC 240   2022-01-16   
240-924 A HGTWMDHGDMD  071F BANDWIDTH.COM CLEC, LLC - MD 240      
240-924 0   071F BANDWIDTH.COM CLEC, LLC - MD 240   2022-04-15   
240-924 1   071F BANDWIDTH.COM CLEC, LLC - MD 240   2022-04-15   
240-924 2   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 3   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 4   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 5   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 6   876D ONVOY, LLC - MD 240   2023-08-10   
240-924 7   876D ONVOY, LLC - MD 240   2024-04-05   
240-924 8   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2024-11-05   
240-924 9   939H COMMIO, LLC 240   2022-11-17   
301-703 A FRDRMDFRXMD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 240      
301-703 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 240   2014-05-05   
301-703 1   318J COMCAST IP PHONE, LLC 240   2015-09-17   
301-703 2   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 240   2006-05-20   
301-703 3   829J PAETEC ITEL, LLC 240   2009-11-16   
301-703 4   9212 VERIZON MARYLAND, INC. 240   2004-11-17   
301-703 5   318J COMCAST IP PHONE, LLC 240   2012-05-26   
301-703 6   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 240   2013-06-10   
301-703 7   624H ONVOY SPECTRUM, LLC 240   2021-11-08   
301-703 8   318J COMCAST IP PHONE, LLC 240   2007-04-07   
301-703 9   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 240   2005-02-17   
301-829 A MTARMDMARS1  9212 VERIZON MARYLAND, INC. 240      
301-829 0   9212 VERIZON MARYLAND, INC. 240      
301-829 1   9212 VERIZON MARYLAND, INC. 240      
301-829 2   9212 VERIZON MARYLAND, INC. 240      
301-829 3   9212 VERIZON MARYLAND, INC. 240      
301-829 4   9212 VERIZON MARYLAND, INC. 240      
301-829 5   9212 VERIZON MARYLAND, INC. 240      
301-829 6   9212 VERIZON MARYLAND, INC. 240      
301-829 7   9212 VERIZON MARYLAND, INC. 240   2001-11-03   
301-829 8   9212 VERIZON MARYLAND, INC. 240      
301-829 9   9212 VERIZON MARYLAND, INC. 240      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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