Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 410 [Rate centres in NPA 410] [Dial plan for NPA 410]

NXX: 346

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
410-346 A Silver Run MD SLRNMDSLRS0  9212 VERIZON MARYLAND, INC. 238      
410-346 0 Silver Run MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-04   
410-346 1 Silver Run MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-08   
410-346 2 Silver Run MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-07-08   
410-346 3 Silver Run MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-04   
410-346 4 Silver Run MD BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2003-12-25   
410-346 5 Silver Run MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-03-05   
410-346 6 Silver Run MD SLRNMDSLRS0  9212 VERIZON MARYLAND, INC. 238      
410-346 7 Silver Run MD SLRNMDSLRS0  9212 VERIZON MARYLAND, INC. 238      
410-346 8 Silver Run MD SLRNMDSLRS0  9212 VERIZON MARYLAND, INC. 238   2006-07-27   
410-346 9 Silver Run MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-28   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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