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: 477

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-477 A Gaithersburg MD HRNDVACKBMD  5966 LIGHTWAVE COMMUNICATIONS, LLC - MD 236      
240-477 0 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
240-477 1 Gaithersburg MD HRNDVACKBMD  5966 LIGHTWAVE COMMUNICATIONS, LLC - MD 236      
240-477 2 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
240-477 3 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
240-477 4 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
240-477 5 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
240-477 6 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
240-477 7 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
240-477 8 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      
240-477 9 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

Sponsored by: VoIP.ms

Like this site? We accept donations via PayPal.