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: 644

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-644 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 0 Frederick MD FRDRMDFRIMD  551G NUSO, LLC 240   2018-11-07   
301-644 1 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 2 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 3 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 4 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 5 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 6 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 7 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 8 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-644 9 Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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