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: ROCHMNHI8MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
507-974 A Rochester MN 475J CALLWORKS CORPORATION 620   2024-02-02   
507-974 1 Rochester MN 475J CALLWORKS CORPORATION 620   2024-02-02   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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