Cook County Commercial and Industrial Property Tax Assessments

This download includes three different data sets that were provided to ProPublica Illinois and the Chicago Tribune by the Cook County Assessor's Office. The three datasets are: 

  • The raw first-pass or initial assessment values and market values for each property, identified only by its Property Index Number (PIN), which is unique for each parcel of property. Covers 2002-2015 
  • Property assessment data on each PIN that was the subject of an appeal, including property information, as well as initial assessed values, second-pass assessed values, and the final assessed values (incorporating any successful appeals to the Cook County Board of Review), as well as attorney names. Covers 2003-2016.
  • The raw final assessed values that were submitted to the Cook County Board of Review by the Cook County Assessor's office for each PIN. Covers 2002-2015.

The Assessor's Office did not provide documentation.

Chicago Tribune

Provided in collaboration with Chicago Tribune

ProPublica & Chicago Tribune

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Part of these collections:

ProPublica Illinois and Cook County