Cook County Assessor’s Property Tax Rate Simulator Tool

The excel file below is a Property Tax Rate Simulator tool. The tool simulates effective tax rates and total property tax bills for user-input property values for single-family homes (200-class), commercial apartments (300-class), and commercial and industrial (500-class) properties in the City of Chicago. To accomplish these simulations, the workbook contains data and models to demonstrate how individual assessments, levies, and overall tax bases interact to produce a Chicago tax bill.

The purpose of this simulator is twofold. First, it demonstrates how historical tax bills can be simulated using mostly publicly-available data. Second, it demonstrates how one might explore hypothetical property tax scenarios in order to better understand the workings of the Cook County property tax system. Note that the Cook County Assessor does not calculate tax rates or tax bills. You can read about Cook County’s property tax system here.

The “Simulating Bills” tab can be used to simulate property tax bills between 2006-2018, and compare them side-by-side. The “Simulating Scenarios” tab can be used to simulate an alternate, fictional version of 2018 with built-in scenarios.

This tool is for educational purposes only. The Assessor’s office releases the tool without any representations or warranties of any kind, whether express or implied. Any data, figures, or amounts contained within the tool, used by the tool, or produced by the tool are solely for illustrative purposes. Any results produced by this tool as distributed are not intended to be predictive and should not be relied upon for any business or commercial purpose. They merely demonstrate the tool’s features. The Assessor’s office expressly disclaims any liability for any entity’s reliance on this tool.

These simulated tax bills do not take into account effects of homeowner exemptions and do not apply to properties inside of Special Service Areas (SSAs). The tool uses data about taxing districts and TIFs in place for the 2017 and 2018 tax years. The data driving this tool did not directly produce any tax bills, and all inferences drawn from this data should be considered purely speculative. We also strongly recommend reading the Technical Documentation for this tool.

Click Excelhere to download the Cook County Assessor’s Property Tax Rate Simulator. This tool is a Microsoft Excel file.

Update December 16, 2019: Some of the content in the Simulator is locked to prevent editing. For new or non-advanced users we recommend keeping it locked, which still allows the user to enter property values, select property class, simulate previous historical tax bills, and use alternative 2018 scenarios. Should you wish to unlock the Simulator to make your own modifications, the password is data. You can always re-download the tool from this website.

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