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.

Parkville, MD

<< 1 2 3 4 5 6 >>

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-425 2   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-05-21   
443-425 3   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-425 4   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 5   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 9   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2015-06-30   
443-442 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-442 0   829J PAETEC ITEL, LLC 238      
443-442 1   829J PAETEC ITEL, LLC 238      
443-442 2   829J PAETEC ITEL, LLC 238      
443-442 3   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-05-11   
443-442 4   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2014-07-01   
443-442 5   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-05-11   
443-442 6   318J COMCAST IP PHONE, LLC 238   2014-07-18   
443-442 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2015-10-01   
443-442 8   829J PAETEC ITEL, LLC 238      
443-442 9   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-11-04   
443-461 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-461 0   829J PAETEC ITEL, LLC 238      
443-461 1   829J PAETEC ITEL, LLC 238      
443-461 2   829J PAETEC ITEL, LLC 238      
443-461 3   829J PAETEC ITEL, LLC 238      
443-461 4   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-03-02   
443-461 5   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-03-02   
443-461 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-03-02   
443-461 7   515J IP HORIZON LLC 238   2016-10-14   
443-461 8   073H TELNYX LLC 238   2017-03-14   
443-461 9   829J PAETEC ITEL, LLC 238      
443-495 A   071F BANDWIDTH.COM CLEC, LLC - MD 238      
443-495 1   145J TERRA NOVA TELECOM INC. 238   2025-07-25   
443-495 2   318J COMCAST IP PHONE, LLC 238   2016-05-18   
443-495 3   071F BANDWIDTH.COM CLEC, LLC - MD 238   2017-07-31   
443-495 4   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-09-29   
443-495 5   071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-12   
443-495 6   876D ONVOY, LLC - MD 238   2018-05-27   
443-495 7   318J COMCAST IP PHONE, LLC 238   2015-09-25   
443-495 8   964H BARR TELL USA, INC. 238   2016-12-17   
443-495 9   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2015-08-14   
443-588 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 1   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 3   829J PAETEC ITEL, LLC 238   2015-09-04   
443-588 4   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 5   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 6   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
443-588 7   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-588 8   318J COMCAST IP PHONE, LLC 238   2015-04-13   

<< 1 2 3 4 5 6 >>

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

Sponsored by: VoIP.ms

Like this site? We accept donations via PayPal.