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: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
410-237 A Baltimore MD BLTMMDCH1DD  9212 VERIZON MARYLAND, INC. 238      
410-237 0 Baltimore MD   551G NUSO, LLC 238   2018-07-23   
410-237 1 Baltimore MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-02-14   
410-237 2 Baltimore MD   9212 VERIZON MARYLAND, INC. 238      
410-237 3 Baltimore MD   9212 VERIZON MARYLAND, INC. 238      
410-237 4 Baltimore MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-23   
410-237 5 Baltimore MD   9212 VERIZON MARYLAND, INC. 238      
410-237 6 Baltimore MD   876D ONVOY, LLC - MD 238   2017-06-02   
410-237 7 Baltimore MD   876D ONVOY, LLC - MD 238   2017-12-01   
410-237 8 Baltimore MD   876D ONVOY, LLC - MD 238   2017-12-01   
410-237 9 Baltimore MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-02-14   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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