Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 378

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-378 A Frederick MD FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240      
301-378 0 Frederick MD FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240      
301-378 1 Frederick MD FRDRMDFRPMD  2589 US LEC OF MARYLAND, INC. 240      
301-378 2 Frederick MD FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240      
301-378 3 Frederick MD FRDRMDFR9MD  5562 METROPCS, INC. 240      
301-378 4 Frederick MD FRDRMDFR9MD  5562 METROPCS, INC. 240      
301-378 5 Frederick MD FRDRMDFR9MD  5562 METROPCS, INC. 240      
301-378 6 Frederick MD HGTWMD53BMD  145J TERRA NOVA TELECOM INC. 240      
301-378 7 Frederick MD FRDRMDFRXAX  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 240      
301-378 8 Frederick MD FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240      
301-378 9 Frederick MD FRDRMDFRXTX  318J COMCAST IP PHONE, LLC 240      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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