Cook County property tax is an ad valorem tax. Formula: the Assessor sets a market value and applies an assessment level (10% residential, 25% commercial) to get the Assessed Valuation; the state applies an Equalization Factor to get the Equalized Assessed Value (EAV); exemptions are subtracted; then the local Composite Tax Rate is applied to determine the bill. View data via the Cook County Property Tax Portal or Clerk's site.
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What is a Cook County property tax and how is it calculated?
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