Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Washington Zone 11, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-761 7   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2014-10-23   
301-761 8   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2014-11-22   
301-761 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-770 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-816 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-822 A WASHDCSWX2Z  7421 AT&T LOCAL 236      
301-822 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 1   2593 CORE COMMUNICATIONS, INC. - MD 236   2018-10-24   
301-822 2   876D ONVOY, LLC - MD 236   2016-02-09   
301-822 3   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 4   318J COMCAST IP PHONE LLC 236   2013-10-03   
301-822 5   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 6   2593 CORE COMMUNICATIONS, INC. - MD 236   2018-10-24   
301-822 7   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 8   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-822 9   7421 AT&T LOCAL 236      
301-871 A SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-881 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-929 A WHTNMDWTDS0  9212 VERIZON MARYLAND, INC. 236      
301-933 A WHTNMDWTDS0  9212 VERIZON MARYLAND, INC. 236      
301-942 A WHTNMDWTDS0  9212 VERIZON MARYLAND, INC. 236      
301-945 A WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-945 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-945 1   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-945 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-945 3   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2015-05-18   
301-945 4   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-945 5   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-01-25   
301-945 6   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-945 7   876D ONVOY, LLC - MD 236   2014-10-27   
301-945 8   876D ONVOY, LLC - MD 236   2014-10-27   
301-945 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-946 A WHTNMDWTDS0  9212 VERIZON MARYLAND, INC. 236      
301-949 A WHTNMDWTDS0  9212 VERIZON MARYLAND, INC. 236      
301-962 A WHTNMDWTDS0  9212 VERIZON MARYLAND, INC. 236      
301-962 0   9212 VERIZON MARYLAND, INC. 236      
301-962 1   9212 VERIZON MARYLAND, INC. 236      
301-962 2   568G PEERLESS NETWORK OF MARYLAND, LLC 236   2019-03-07   
301-962 3   9212 VERIZON MARYLAND, INC. 236      
301-962 4   9212 VERIZON MARYLAND, INC. 236      
301-962 5   9212 VERIZON MARYLAND, INC. 236      
301-962 6   9212 VERIZON MARYLAND, INC. 236      
301-962 7   9212 VERIZON MARYLAND, INC. 236      
301-962 8   9212 VERIZON MARYLAND, INC. 236      
301-962 9   9212 VERIZON MARYLAND, INC. 236      
301-984 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-998 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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