Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Washington Zone 3, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-537 7 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
301-537 8 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
301-537 9 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
301-551 A VINNVACB2MD  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 236      
301-557 A MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
301-557 0 BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2014-09-12   
301-557 1 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 2 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 3 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 4 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 5 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 6 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 7 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 8 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-10-29   
301-557 9 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2013-09-08   
301-561 A VINNVACB2MD  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 236      
301-562 A SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 A SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 0 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 1 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 2 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 3 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 4 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 5 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 6 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 7 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 8 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 9 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2007-12-04   
301-565 A SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-572 A BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-576 A CHCHMDBE6MD  4716 PAETEC COMMUNICATIONS, INC. - MD 236      
301-578 A SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 0 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 1 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 2 WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2020-06-13   
301-578 3 WASHDC126MD  964H BARR TELL USA, INC. 236   2018-05-08   
301-578 4 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 5 WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2020-06-13   
301-578 6 WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2018-07-19   
301-578 7 WASIDCRG7MD  508J CENTURYLINK COMMUNICATIONS, LLC 236   2018-03-12   
301-578 8 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 9 SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-580 A WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236      
301-585 A SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-586 A BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-586 0 BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-586 1 BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-586 2 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-11-21   
301-586 3 BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-586 4 BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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