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: 371

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-371 A Middletown MD BRHGMDBHRS1  9212 VERIZON MARYLAND, INC. 240      
301-371 0 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 1 Middletown MD   2593 CORE COMMUNICATIONS, INC.- MD 240   2004-03-28   
301-371 2 Middletown MD   071F BANDWIDTH.COM CLEC, LLC - MD 240   2007-06-04   
301-371 3 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 4 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 5 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 6 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 7 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 8 Middletown MD   9212 VERIZON MARYLAND, INC. 240      
301-371 9 Middletown MD   9212 VERIZON MARYLAND, INC. 240      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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