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: 578

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-578 A Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 0 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 1 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 2 Washington Zone 3 MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2020-06-13   
301-578 3 Washington Zone 3 MD WASHDC126MD  964H BARR TELL USA, INC. 236   2018-05-08   
301-578 4 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 5 Washington Zone 3 MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2020-06-13   
301-578 6 Washington Zone 3 MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2018-07-19   
301-578 7 Washington Zone 3 MD WASIDCRG7MD  508J CENTURYLINK COMMUNICATIONS, LLC 236   2018-03-12   
301-578 8 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      
301-578 9 Washington Zone 3 MD SLSPMDSSDS0  9212 VERIZON MARYLAND, INC. 236      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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