Local Calling Guide

Area code/prefix search

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Washington Zone 4, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-772 A LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-773 A LDVRMDLODS0  9212 VERIZON MARYLAND, INC. 236      
301-779 A HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-781 A WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236      
301-781 0 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 1 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 2 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 3 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 4 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 5 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 6 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 7 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 8 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-781 9 WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-06-18   
301-789 A CHCHMDBEPS0  2593 CORE COMMUNICATIONS, INC.- MD 236   2024-01-16   
301-789 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2002-10-05   
301-789 1   829J PAETEC ITEL, LLC 236   2005-02-10   
301-789 2   829J PAETEC ITEL, LLC 236   2005-02-10   
301-789 3 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-02-15   
301-789 4 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-11-15   
301-789 5 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-04-20   
301-789 6 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-04-20   
301-789 7 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-04-20   
301-789 8 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-11-15   
301-789 9 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-02-15   
301-832 A WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-832 0 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-06-05   
301-832 1 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-07-03   
301-832 2 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-02-15   
301-832 3   829J PAETEC ITEL, LLC 236   2006-06-24   
301-832 4 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-09-01   
301-832 5 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-10-03   
301-832 6 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-11-03   
301-832 7 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2009-09-09   
301-832 8 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2009-06-01   
301-832 9 WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-851 A HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-851 0 VINNVACBDS0  876D ONVOY, LLC - MD 236   2014-08-29   
301-851 1 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2014-10-10   
301-851 2 HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-851 3 HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-851 4 HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-851 5 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2014-12-12   
301-851 6 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-02-29   
301-851 7 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-851 8 HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-851 9 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2014-10-10   
301-852 A HYVLMDHYDS0  9212 VERIZON MARYLAND, INC. 236      
301-852 0 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2010-02-06   
301-852 1 WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2010-06-03   

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

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