Local Calling Guide

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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-600 8 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-600 9 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240   2006-08-27   
301-601 A Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-602 A Washington Zone 3 MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236      
301-603 A Washington Zone 11 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 0 Washington Zone 11 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 1 Washington Zone 11 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 2 Washington Zone 11 MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2016-07-13   
301-603 3 Washington Zone 11 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2015-06-27   
301-603 4 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-603 5 Washington Zone 11 MD WASHDC126MD  964H BARR TELL USA, INC. 236   2018-05-08   
301-603 6 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-07-30   
301-603 7 Washington Zone 11 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 8 Washington Zone 11 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 9 Washington Zone 11 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-604 A Laurel MD LARLMDLRDS0  9212 VERIZON MARYLAND, INC. 236      
301-605 A Washington Zone 10 MD PLVLMDPVRS2  9212 VERIZON MARYLAND, INC. 236      
301-605 0 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2014-09-25   
301-605 1 Washington Zone 10 MD   829J PAETEC ITEL, LLC 236   2009-11-10   
301-605 2 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-06-16   
301-605 3 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-06-16   
301-605 4 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-02-16   
301-605 5 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-03-25   
301-605 6 Washington Zone 10 MD PLVLMDPVRS2  9212 VERIZON MARYLAND, INC. 236      
301-605 7 Washington Zone 10 MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2007-05-02   
301-605 8 Washington Zone 10 MD LARLMDCCDS0  4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 236   2004-04-06   
301-605 9 Washington Zone 10 MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2012-01-14   
301-606 A Frederick MD FRDRMDFRXSX  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 240      
301-607 A Damascus (Hagerstown LATA) MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-607 0 Damascus (Hagerstown LATA) MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-607 1 Damascus (Hagerstown LATA) MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-607 2 Damascus (Hagerstown LATA) MD FRDRMDFRX7X  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 240      
301-607 3 Damascus (Hagerstown LATA) MD FRDRMDFRX7X  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 240      
301-607 4 Damascus (Hagerstown LATA) MD BCTWMDBTRS1  9212 VERIZON MARYLAND, INC. 240      
301-607 5 Damascus (Hagerstown LATA) MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-607 6 Damascus (Hagerstown LATA) MD NWMRMDNERS3  9212 VERIZON MARYLAND, INC. 240      
301-607 7 Damascus (Hagerstown LATA) MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-607 8 Damascus (Hagerstown LATA) MD MTARMDMARS1  9212 VERIZON MARYLAND, INC. 240      
301-607 9 Damascus (Hagerstown LATA) MD MTARMDMARS1  9212 VERIZON MARYLAND, INC. 240      
301-608 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-609 A Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      
301-609 0 Waldorf MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-02-02   
301-609 1 Waldorf MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-02-02   
301-609 2 Waldorf MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2007-03-05   
301-609 3 Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      
301-609 4 Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      
301-609 5 Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      
301-609 6 Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      
301-609 7 Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      
301-609 8 Waldorf MD LPLTMDLADS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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