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.

Switch: WASHDCSWFMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
202-666 A Washington Zone 1 DC 538H WIDE VOICE, LLC - DC 236      
202-851 A Washington Zone 1 DC 538H WIDE VOICE, LLC - DC 236      
227-222 A Washington Zone 16 MD 530H WIDE VOICE, LLC - MD 236      
227-368 A Mechanicsville MD 530H WIDE VOICE, LLC - MD 236      
227-999 A Washington Zone 10 MD 530H WIDE VOICE, LLC - MD 236      
771-333 A Washington Zone 1 DC 538H WIDE VOICE, LLC - DC 236      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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