Local Calling Guide

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NPA: 240 [Rate centres in NPA 240] [Dial plan for NPA 240]

NXX: 583

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-583 A Laurel MD MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236      
240-583 0 Laurel MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-08-14   
240-583 1 Laurel MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-10-28   
240-583 2 Laurel MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2010-06-12   
240-583 3 Laurel MD MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 4 Laurel MD MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 5 Laurel MD MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 6 Laurel MD MRKKMDMKDS0  9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 7 Laurel MD WASHDCDP8MD  071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-08-19   
240-583 8 Laurel MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2010-09-02   
240-583 9 Laurel MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2011-07-22   

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

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