Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 304 [Rate centres in NPA 304] [Dial plan for NPA 304]

NXX: 350

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
304-350 A Martinsburg WV   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240      
304-350 0 Martinsburg WV FRDRMDFRKMD  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2010-12-24   
304-350 1 Martinsburg WV FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240   2013-04-26   
304-350 2 Martinsburg WV FRDRMDFRXSX  6394 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WV 240   2016-05-06   
304-350 3 Martinsburg WV   9944 LEVEL 3 COMMUNICATIONS, LLC - WV 240   2010-05-30   
304-350 4 Martinsburg WV FRDRMDFRXAX  077G TELEPORT COMMUNICATIONS AMERICA, LLC - WV 240   2013-09-23   
304-350 5 Martinsburg WV FRDRMDFRXAX  077G TELEPORT COMMUNICATIONS AMERICA, LLC - WV 240   2013-09-23   
304-350 6 Martinsburg WV FRDRMDFRXAX  077G TELEPORT COMMUNICATIONS AMERICA, LLC - WV 240   2013-09-23   
304-350 7 Martinsburg WV FRDRMDFRKMD  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2016-12-09   
304-350 8 Martinsburg WV FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240   2013-12-28   
304-350 9 Martinsburg WV FRDRMDFRKMD  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2014-04-28   

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

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