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: HRFRCT03HMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
475-234 A New Haven CT 073H TELNYX LLC 920      
475-333 A Stamford CT 073H TELNYX LLC 920      
959-222 A New Britain CT 073H TELNYX LLC 920      

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

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