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: 397

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-397 A Washington Zone 13 MD CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-397 0 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 1 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 2 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 3 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-397 4 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 5 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 6 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 7 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-397 8 Washington Zone 13 MD   9212 VERIZON MARYLAND, INC. 236      
301-397 9 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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