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: STLSMOGZSMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
557-999 A Sappington MO 733J WIRETAP TELECOM, LLC. 520      
557-999 7 Sappington MO 733J WIRETAP TELECOM, LLC. 520   2023-05-13   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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