Local Calling Guide

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NPA: 740 [Rate centres in NPA 740] [Dial plan for NPA 740]

NXX: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
740-400 A Baltimore OH CLMKOHPE0MD  793K TWC IP ENABLED SERVICES, LLC 324   2025-02-04   
740-400 0 Baltimore OH CLMBOH11XLZ  001F BANDWIDTH.COM CLEC, LLC - OH 324   2012-01-27   
740-400 1 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2014-10-20   
740-400 2 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2016-09-30   
740-400 3 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2016-03-29   
740-400 4 Baltimore OH CLMKOHPE0MD  793K TWC IP ENABLED SERVICES, LLC 324   2007-02-14   
740-400 5 Baltimore OH   145J TERRA NOVA TELECOM INC. 324   2025-09-15   
740-400 6 Baltimore OH CLMBOH1125Z  508J CENTURYLINK COMMUNICATIONS, LLC 324   2014-07-03   
740-400 7 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2017-08-15   
740-400 8 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2015-10-23   
740-400 9 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2015-05-15   

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

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