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: CHSLMIMNRSA

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
906-523 A Houghton MI 9323 MICHIGAN BELL TEL CO 342      
906-523 4 Houghton MI 9323 MICHIGAN BELL TEL CO 342      
906-523 6 Houghton MI 9323 MICHIGAN BELL TEL CO 342      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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