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: HRSPMIMNRSA

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
231-242 A Harbor Springs MI 9323 MICHIGAN BELL TEL CO 348      
231-526 A Harbor Springs MI 9323 MICHIGAN BELL TEL CO 348      

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

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