Local Calling Guide

Area code/prefix search

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Washington Zone 10, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-545 0   9212 VERIZON MARYLAND, INC. 236      
301-545 1   9212 VERIZON MARYLAND, INC. 236      
301-545 2   318J COMCAST IP PHONE, LLC 236   2017-08-17   
301-545 3   964H BARR TELL USA, INC. 236   2018-05-08   
301-545 4   9212 VERIZON MARYLAND, INC. 236      
301-545 5   9212 VERIZON MARYLAND, INC. 236      
301-545 6   9212 VERIZON MARYLAND, INC. 236      
301-545 7   9212 VERIZON MARYLAND, INC. 236      
301-545 8   9212 VERIZON MARYLAND, INC. 236      
301-545 9   9212 VERIZON MARYLAND, INC. 236      
301-548 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-550 A BTVLMD18G00  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-550 0   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2022-09-10   
301-550 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2022-09-10   
301-550 2   876D ONVOY, LLC - MD 236   2022-10-15   
301-550 3   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2022-10-17   
301-550 4   5562 METROPCS, INC. 236   2022-11-14   
301-550 5   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-09-09   
301-550 6   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-09-09   
301-550 7   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-09-09   
301-550 8   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-09-09   
301-550 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-09-09   
301-590 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-590 0   9212 VERIZON MARYLAND, INC. 236      
301-590 1   9212 VERIZON MARYLAND, INC. 236      
301-590 2   9212 VERIZON MARYLAND, INC. 236      
301-590 3   9212 VERIZON MARYLAND, INC. 236      
301-590 4   9212 VERIZON MARYLAND, INC. 236      
301-590 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2014-09-16   
301-590 6   9212 VERIZON MARYLAND, INC. 236      
301-590 7   9212 VERIZON MARYLAND, INC. 236      
301-590 8   9212 VERIZON MARYLAND, INC. 236      
301-590 9   9212 VERIZON MARYLAND, INC. 236      
301-601 A GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-605 A PLVLMDPVRS2  9212 VERIZON MARYLAND, INC. 236      
301-605 0   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2014-09-25   
301-605 1   829J PAETEC ITEL, LLC 236   2009-11-10   
301-605 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-06-16   
301-605 3   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-06-16   
301-605 4   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-02-16   
301-605 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-03-25   
301-605 6   9212 VERIZON MARYLAND, INC. 236      
301-605 7   318J COMCAST IP PHONE, LLC 236   2007-05-02   
301-605 8   4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 236   2004-04-06   
301-605 9   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2012-01-14   
301-610 A RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      
301-610 0   9212 VERIZON MARYLAND, INC. 236      
301-610 1   9212 VERIZON MARYLAND, INC. 236      
301-610 2   9212 VERIZON MARYLAND, INC. 236      
301-610 3   876D ONVOY, LLC - MD 236   2020-04-30   

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

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