Local Calling Guide

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

NXX: 556

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
740-556 A Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324      
740-556 0 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2023-07-30   
740-556 1 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2023-07-30   
740-556 2 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2023-07-30   
740-556 3 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2023-07-30   
740-556 4 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2023-10-27   
740-556 5 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2023-10-27   
740-556 6 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2023-10-21   
740-556 7 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2023-09-18   
740-556 8 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2023-02-09   
740-556 9 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2022-10-10   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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