Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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   071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-08-14   
240-583 1 Laurel MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-10-28   
240-583 2 Laurel MD   9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 3 Laurel MD   9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 4 Laurel MD   9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 5 Laurel MD   9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 6 Laurel MD   9212 VERIZON MARYLAND, INC. 236   2010-06-12   
240-583 7 Laurel MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2010-08-19   
240-583 8 Laurel MD   4773 XO MARYLAND, LLC 236   2010-09-02   
240-583 9 Laurel MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2011-07-22   

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.