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: STLSMOPL7MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
557-250 A St Louis MO 671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 520   2026-04-28   
557-250 3 St Louis MO 671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 520   2026-04-28   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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