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: 360

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-360 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-360 0 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 1 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 2 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 3 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 4 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 5 Frederick MD   318J COMCAST IP PHONE, LLC 240   2016-02-09   
301-360 6 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 7 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 8 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-360 9 Frederick MD   9212 VERIZON MARYLAND, INC. 240      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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