Local Calling Guide

Area code/prefix search

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Washington Zone 14, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-850 7 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-08-10   
301-850 8 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2017-02-04   
301-850 9   829J PAETEC ITEL, LLC 236   2004-03-27   
301-860 A BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 0 BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 1 BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 2 BTVLMD12CMA  5562 METROPCS, INC. 236   2016-12-25   
301-860 3 BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 4 BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 5 BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 6 BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-860 7 BTVLMD12CMA  5562 METROPCS, INC. 236   2015-02-05   
301-860 8   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-860 9 BTVLMD12CMA  5562 METROPCS, INC. 236   2018-04-16   
301-867 A WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-867 0 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-867 1 OCQNVAXAVMD  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236   2020-08-10   
301-867 2 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-867 3   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-867 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-867 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-03-14   
301-867 6 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-867 7 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-03-14   
301-867 8 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-867 9 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      

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Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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