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: 631

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-631 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-631 0 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 1 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 2 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 3 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 4 Frederick MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2015-11-27   
301-631 5 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 6 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 7 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 8 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-631 9 Frederick MD   9212 VERIZON MARYLAND, INC. 240      

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

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