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Washington Zone 16, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-235 A WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-235 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2004-03-26   
301-235 1 VINNVACBDS0  876D ONVOY, LLC - MD 236   2019-02-19   
301-235 2 VINNVACBDS0  876D ONVOY, LLC - MD 236   2018-06-08   
301-235 3 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2015-09-02   
301-235 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-235 5 WASHDC126MD  964H BARR TELL USA, INC. 236   2018-05-08   
301-235 6 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-05-22   
301-235 7   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-235 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2019-02-19   
301-235 9 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-238 A TMHLMDTHDS0  9212 VERIZON MARYLAND, INC. 236      
301-238 0 TMHLMDTHDS0  9212 VERIZON MARYLAND, INC. 236   2001-12-21   
301-238 1 TMHLMDTHDS0  9212 VERIZON MARYLAND, INC. 236   2004-07-10   
301-238 2 TMHLMDTHDS0  9212 VERIZON MARYLAND, INC. 236      
301-238 3 TMHLMDTHDS0  9212 VERIZON MARYLAND, INC. 236      
301-238 4   829J PAETEC ITEL, LLC 236   2005-02-08   
301-238 5   829J PAETEC ITEL, LLC 236   2007-02-23   
301-238 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-03-29   
301-238 7 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-03-30   
301-238 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-03-30   
301-238 9 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-05-22   
301-297 A ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 0 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 1 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 2 VINNVACBDS0  876D ONVOY, LLC - MD 236   2025-01-09   
301-297 3 VINNVACBDS0  876D ONVOY, LLC - MD 236   2021-04-02   
301-297 4 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 5 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 6 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 7 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 8 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-297 9 ALTWMDATRP0  9212 VERIZON MARYLAND, INC. 236      
301-372 A BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 0 BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 1 BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 2 BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 3 BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-03-29   
301-372 5   829J PAETEC ITEL, LLC 236   2016-06-17   
301-372 6 BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 7 WASIDCRG7MD  508J CENTURYLINK COMMUNICATIONS, LLC 236   2014-06-25   
301-372 8 BRNDMDBERS0  9212 VERIZON MARYLAND, INC. 236      
301-372 9 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-05-22   
301-719 A WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-719 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-719 1 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-719 2 VINNVACBDS0  876D ONVOY, LLC - MD 236   2020-04-30   
301-719 3 VINNVACBDS0  876D ONVOY, LLC - MD 236   2020-04-30   
301-719 4 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-05-22   

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Last updated: Sun, 17 May 2026 03:26:51 UTC

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