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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
301-557 9 Washington Zone 3 MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2013-09-08   
301-558 A Washington Zone 13 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-08-28   
301-558 2 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-09-28   
301-558 3 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-09-28   
301-558 4 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-09-28   
301-558 5 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-08-29   
301-558 6 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-09-28   
301-558 7 Washington Zone 13 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-09-25   
301-558 8 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-08-29   
301-558 9 Washington Zone 13 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-08-28   
301-559 A Washington Zone 4 MD HYVLMDCMDS0  9212 VERIZON MARYLAND, INC. 236      
301-560 A Washington Zone 4 MD   829J PAETEC ITEL, LLC 236   2025-04-02   
301-561 A Washington Zone 3 MD VINNVACB2MD  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 236      
301-562 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 0 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 1 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 2 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 3 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 4 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 5 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 6 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 7 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 8 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-563 9 Washington Zone 3 MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2007-12-04   
301-564 A Washington Zone 2 MD BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-565 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-566 A Washington Zone 13 MD MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
301-567 A Washington Zone 6 MD OXHLMDOHDS0  9212 VERIZON MARYLAND, INC. 236      
301-568 A Washington Zone 5 MD STLDMDSLDS0  9212 VERIZON MARYLAND, INC. 236      
301-569 A Gaithersburg MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236      
301-569 0 Gaithersburg MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2013-09-17   
301-569 1 Gaithersburg MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2014-05-01   
301-569 2 Gaithersburg MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2011-05-07   
301-569 3 Gaithersburg MD WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2014-06-01   
301-569 4 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2013-12-10   
301-569 5 Gaithersburg MD WASIDCRG7MD  508J CENTURYLINK COMMUNICATIONS, LLC 236   2013-10-01   
301-569 6 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2011-09-08   
301-569 7 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2012-01-14   
301-569 8 Gaithersburg MD WASLDCRGDS0  281E YMAX COMMUNICATIONS CORP. - MD 236   2011-09-02   
301-569 9 Gaithersburg MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2012-04-05   
301-570 A Ashton MD OLNYMDOKRP0  9212 VERIZON MARYLAND, INC. 236      
301-571 A Washington Zone 2 MD BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-572 A Washington Zone 3 MD BTVLMDBVDS0  9212 VERIZON MARYLAND, INC. 236      
301-573 A Hagerstown MD FRDRMDFRKMD  5562 METROPCS, INC. 240      
301-573 0 Hagerstown MD FRDRMDFRKMD  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240      
301-573 1 Hagerstown MD FRDRMDFRKMD  5562 METROPCS, INC. 240      
301-573 2 Hagerstown MD FRDRMDFRKMD  5562 METROPCS, INC. 240      
301-573 3 Hagerstown MD FRDRMDFRKMD  5562 METROPCS, INC. 240      
301-573 4 Hagerstown MD FRDRMDFRKMD  5562 METROPCS, INC. 240      

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

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