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.
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Switch: SNLOCA01XLY

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
820-400 A Parkfield CA 506J TWILIO INTERNATIONAL, INC. 740      
820-400 9 Parkfield CA 506J TWILIO INTERNATIONAL, INC. 740      

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

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