Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Washington Zone 11, MD

<< 1 2 3 4 5 6 7 >>

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-287 0 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-287 1   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-287 2 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-287 3 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-287 4 VINNVACBDS0  876D ONVOY, LLC - MD 236   2017-12-08   
301-287 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2017-12-08   
301-287 6 VINNVACBDS0  876D ONVOY, LLC - MD 236   2017-12-08   
301-287 7   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-03-29   
301-287 8 HRNDVACKAMD  1958 ATX TELECOMMUNICATIONS SERVICES, LTD. 236   2004-03-27   
301-287 9 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-321 A VINNVACBDS0  876D ONVOY, LLC - MD 236      
301-321 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-321 1 SLSPMD913MD  939H COMMIO, LLC 236   2021-08-29   
301-321 2   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-321 3 HRNDVACKBMD  5977 BROADVIEW NETWORKS, INC. - DC 236   2014-06-09   
301-321 4 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-321 5 RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236   2005-12-12   
301-321 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-321 7 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-01-07   
301-321 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-01-07   
301-321 9   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-348 A WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-348 0   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-348 1 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-348 2   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-348 3 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-348 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-348 5 WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2017-08-03   
301-348 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2012-08-26   
301-348 7   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-07-30   
301-348 8 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2016-02-24   
301-348 9   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-382 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-413 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-443 A RKVLMDMRRS1  9212 VERIZON MARYLAND, INC. 236      
301-460 A SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-468 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-522 A RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 A SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 0 SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 1 SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 2 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2016-07-13   
301-603 3 VINNVACBDS0  876D ONVOY, LLC - MD 236   2015-06-27   
301-603 4   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-603 5 WASHDC126MD  964H BARR TELL USA, INC. 236   2018-05-08   
301-603 6   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-07-30   
301-603 7 SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 8 SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-603 9 SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      
301-649 A SLSPMDNWDS0  9212 VERIZON MARYLAND, INC. 236      

<< 1 2 3 4 5 6 7 >>

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

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.