Local Calling Guide

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Washington Zone 2, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-409 3   876D ONVOY, LLC - MD 236   2022-12-12   
301-409 4   876D ONVOY, LLC - MD 236   2022-12-12   
301-409 5   876D ONVOY, LLC - MD 236   2022-12-12   
301-409 6   876D ONVOY, LLC - MD 236   2022-12-12   
301-409 7   624H ONVOY SPECTRUM, LLC 236   2022-03-10   
301-409 8   624H ONVOY SPECTRUM, LLC 236   2022-03-10   
301-409 9   624H ONVOY SPECTRUM, LLC 236   2022-03-10   
301-412 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-435 A BTHSMDRPDS0  9212 VERIZON MARYLAND, INC. 236      
301-451 A BTHSMDRPDS0  9212 VERIZON MARYLAND, INC. 236      
301-469 A BTHSMDBDDS0  9212 VERIZON MARYLAND, INC. 236      
301-480 A BTHSMDRPDS0  9212 VERIZON MARYLAND, INC. 236      
301-492 A CHCHMDBEDS0  9212 VERIZON MARYLAND, INC. 236      
301-493 A BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-496 A BTHSMDRPDS0  9212 VERIZON MARYLAND, INC. 236      
301-500 A WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-500 0   071F BANDWIDTH.COM CLEC, LLC - MD 236   2011-07-31   
301-500 1   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2011-05-13   
301-500 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2011-04-18   
301-500 3   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2011-05-13   
301-500 4   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2010-11-01   
301-500 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2010-11-01   
301-500 6   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2010-11-01   
301-500 7   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2010-11-01   
301-500 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2011-08-01   
301-500 9   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2010-11-01   
301-503 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-530 A BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-538 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-547 A WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-547 0   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-547 1   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2008-03-11   
301-547 2   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-547 3   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-06-04   
301-547 4   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-547 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-01-11   
301-547 6   551G NUSO, LLC 236   2016-08-31   
301-547 7   876D ONVOY, LLC - MD 236   2020-12-03   
301-547 8   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2014-02-21   
301-547 9   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-02-08   
301-554 A SLSPMDSSX6X  6630 USA MOBILITY WIRELESS, INC. 236      
301-564 A BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-571 A BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-581 A BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-594 A BTHSMDRPDS0  9212 VERIZON MARYLAND, INC. 236      
301-633 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-634 A WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-642 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-646 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-648 A BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      

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Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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