Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Washington Zone 14, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-291 8   5562 METROPCS, INC. 236   2017-01-18   
301-291 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-352 A BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-383 A ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
301-383 0   318J COMCAST IP PHONE, LLC 236   2012-11-03   
301-383 1   318J COMCAST IP PHONE, LLC 236      
301-383 2   318J COMCAST IP PHONE, LLC 236   2016-07-12   
301-383 3   5562 METROPCS, INC. 236   2016-09-26   
301-383 4   5562 METROPCS, INC. 236   2017-03-25   
301-383 5   5562 METROPCS, INC. 236   2016-11-25   
301-383 6   5562 METROPCS, INC. 236   2017-07-14   
301-383 7   5562 METROPCS, INC. 236   2017-11-22   
301-383 8   568G PEERLESS NETWORK OF MARYLAND, LLC 236   2013-05-03   
301-383 9   568G PEERLESS NETWORK OF MARYLAND, LLC 236   2013-05-03   
301-390 A UPMRMDCCDS0  9212 VERIZON MARYLAND, INC. 236      
301-430 A UPMRMDCCDS0  9212 VERIZON MARYLAND, INC. 236      
301-430 0   9212 VERIZON MARYLAND, INC. 236      
301-430 1   515J IP HORIZON LLC 236   2016-05-31   
301-430 2   9212 VERIZON MARYLAND, INC. 236      
301-430 3   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-430 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-430 5   9212 VERIZON MARYLAND, INC. 236      
301-430 6   9212 VERIZON MARYLAND, INC. 236      
301-430 7   9212 VERIZON MARYLAND, INC. 236      
301-430 8   9212 VERIZON MARYLAND, INC. 236      
301-430 9   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-464 A BOWIMDBODS0  9212 VERIZON MARYLAND, INC. 236      
301-470 A LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-470 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-470 1   9212 VERIZON MARYLAND, INC. 236      
301-470 2   9212 VERIZON MARYLAND, INC. 236      
301-470 3   9212 VERIZON MARYLAND, INC. 236      
301-470 4   9212 VERIZON MARYLAND, INC. 236      
301-470 5   9212 VERIZON MARYLAND, INC. 236      
301-470 6   9212 VERIZON MARYLAND, INC. 236      
301-470 7   9212 VERIZON MARYLAND, INC. 236      
301-470 8   9212 VERIZON MARYLAND, INC. 236      
301-470 9   9212 VERIZON MARYLAND, INC. 236      
301-666 A WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-666 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-666 1   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-666 2   876D ONVOY, LLC - MD 236   2017-12-14   
301-666 3   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-666 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-666 5   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-666 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2012-08-26   
301-666 7   508J CENTURYLINK COMMUNICATIONS, LLC 236   2014-04-02   
301-666 8   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-666 9   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-677 A WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      

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

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