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: 624

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-624 A Frederick MD FRDRMDFRDS1  9212 VERIZON MARYLAND, INC. 240      
301-624 0 Frederick MD   5562 METROPCS, INC. 240   2019-08-30   
301-624 1 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 2 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 3 Frederick MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2014-12-13   
301-624 4 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 5 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 6 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 7 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 8 Frederick MD   9212 VERIZON MARYLAND, INC. 240      
301-624 9 Frederick MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2014-12-13   

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

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