Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 240 [Rate centres in NPA 240] [Dial plan for NPA 240]

NXX: 843

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-843 A Washington Zone 13 (Baltimore LATA) MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-843 1 Washington Zone 13 (Baltimore LATA) MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-12   
240-843 2 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
240-843 3 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
240-843 4 Washington Zone 13 (Baltimore LATA) MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-843 5 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
240-843 6 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
240-843 7 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
240-843 8 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
240-843 9 Washington Zone 13 (Baltimore LATA) MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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