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Washington Zone 13, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-220 3 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-220 4 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-220 5 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-220 6 VINNVACBDS0  876D ONVOY, LLC - MD 236   2021-02-18   
301-220 7 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-220 8   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-220 9 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-286 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-289 A WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-289 0 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2024-06-24   
301-289 1 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2024-06-24   
301-289 2   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-289 3 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-289 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-289 5   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-289 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-289 7 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2011-08-26   
301-289 8   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-289 9 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-303 A SLSPMDSSX6X  6630 SPOK, INC. 236      
301-308 A SLSPMDSSX6X  6630 SPOK, INC. 236      
301-313 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 0 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 1   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-313 2 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 3 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 4 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2021-02-18   
301-313 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 7 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 8 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-313 9 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-344 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-345 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-369 A LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-389 A LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-389 0 LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-389 1 LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-389 2 VINNVACBDS0  876D ONVOY, LLC - MD 236   2022-08-21   
301-389 3   829J PAETEC ITEL, LLC 236   2006-06-23   
301-389 4 LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-389 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-04-06   
301-389 6 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-04-06   
301-389 7 LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-389 8 LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-389 9 LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      
301-397 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 0 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 1 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 2 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Sat, 02 May 2026 12:20:53 UTC

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