Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 743

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-743 A Indian Head MD INHDMDINRS0  9212 VERIZON MARYLAND, INC. 236      
301-743 0 Indian Head MD   876D ONVOY, LLC - MD 236   2025-01-06   
301-743 1 Indian Head MD   876D ONVOY, LLC - MD 236   2022-08-21   
301-743 2 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 3 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 4 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 5 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 6 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 7 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 8 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      
301-743 9 Indian Head MD   9212 VERIZON MARYLAND, INC. 236      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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