Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 543

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-543 A Arbutus MD ARBTMDARDS0  9212 VERIZON MARYLAND, INC. 238      
443-543 0 Arbutus MD   9212 VERIZON MARYLAND, INC. 238      
443-543 1 Arbutus MD   9212 VERIZON MARYLAND, INC. 238      
443-543 2 Arbutus MD   9212 VERIZON MARYLAND, INC. 238      
443-543 3 Arbutus MD   9212 VERIZON MARYLAND, INC. 238      
443-543 4 Arbutus MD   939H COMMIO, LLC 238   2021-07-05   
443-543 5 Arbutus MD   9212 VERIZON MARYLAND, INC. 238      
443-543 6 Arbutus MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-02   
443-543 7 Arbutus MD   624H ONVOY SPECTRUM, LLC 238   2021-11-26   
443-543 8 Arbutus MD   876D ONVOY, LLC - MD 238   2014-10-06   
443-543 9 Arbutus MD   876D ONVOY, LLC - MD 238   2014-10-06   

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

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