Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Preston, MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-673 A PSTNMDPSRS0  9212 VERIZON MARYLAND, INC. 242      
410-673 0   2593 CORE COMMUNICATIONS, INC.- MD 242   2004-04-03   
410-673 1 PSTNMDPSRS0  9212 VERIZON MARYLAND, INC. 242      
410-673 2 PSTNMDPSRS0  9212 VERIZON MARYLAND, INC. 242      
410-673 3 SLBRMD902MD  073H TELNYX LLC 242   2017-09-13   
410-673 4 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2017-04-14   
410-673 6   2593 CORE COMMUNICATIONS, INC.- MD 242   2019-03-28   
410-673 7 PSTNMDPSRS0  9212 VERIZON MARYLAND, INC. 242      
410-673 8 SLBRMDSBXLX  318J COMCAST IP PHONE, LLC 242   2006-07-31   
410-673 9 PSTNMDPSRS0  9212 VERIZON MARYLAND, INC. 242      
667-238 A ESTNMDBNGT0  2593 CORE COMMUNICATIONS, INC.- MD 242      
667-238 0   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-08-03   
667-238 1   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-08-03   
667-238 2   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-08-03   
667-238 3 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2021-03-05   
667-238 4 SLBRMD90DS0  2593 CORE COMMUNICATIONS, INC.- MD 242   2019-05-02   
667-238 5 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2023-02-12   
667-238 6 SLBRMD90DS0  2593 CORE COMMUNICATIONS, INC.- MD 242   2019-05-02   
667-238 7 SLBRMD90DS0  2593 CORE COMMUNICATIONS, INC.- MD 242   2019-05-02   
667-238 8 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2019-03-04   
667-238 9 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2019-03-04   
667-342 A SLBRMDSBXVX  876D ONVOY, LLC - MD 242      
667-342 0 SLBRMDSBX0X  624H ONVOY SPECTRUM, LLC 242   2023-09-02   
667-342 2 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2021-10-31   
667-342 3 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2021-12-20   
667-342 4 SLBRMDSBXLX  318J COMCAST IP PHONE, LLC 242   2022-07-05   
667-342 5 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2022-12-03   
667-342 6 SLBRMD90BMD  516J TON80 COMMUNICATIONS, LLC 242   2022-03-21   
667-342 7 SLBRMDSBXFX  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242   2022-11-18   
667-342 8 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2022-12-24   
667-342 9 SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2023-06-17   
667-449 A SLBRMD901MD  939H COMMIO, LLC 242      
667-449 0 SLBRMD901MD  939H COMMIO, LLC 242   2023-11-04   
667-449 1 SLBRMD901MD  939H COMMIO, LLC 242   2023-11-04   
667-449 2 SLBRMD901MD  939H COMMIO, LLC 242   2023-11-04   
667-449 3 SLBRMD901MD  939H COMMIO, LLC 242   2023-11-04   
667-449 4 SLBRMD901MD  939H COMMIO, LLC 242   2023-11-04   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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