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Illinois Dept. of Revenue Releases Final 2018 Cook County Equalization Factor

Property Tax Publications

The Illinois Department of Revenue has released the final 2018 Cook County equalization factor. The factor (sometimes referred to as the multiplier) for 2018 is 2.9109. The press release from the Department of Revenue is available here.

Cook County equalization factors for the past 15 years are set forth in the table below.

Tax Year

Final Multiplier

2004

2.5757

2005

2.7320

2006

2.7076

2007

2.8439

2008

2.9786

2009

3.3701

2010

3.3000

2011

2.9706

2012

2.8056

2013

2.6621

2014

2.7253

2015

2.6685

2016

2.8032

2017

2.9627

2018

2.9109

 

The Property Tax Code requires the Department to issue a multiplier that, when applied to the assessed value of all property in a county (except for specially assessed property such as farmland), will result in the aggregate assessed value of all property in the County is 33.33% of the property’s fair cash value. This equalization of assessed values is accomplished by comparing recorded sales prices to assessed values for the three prior years, and it is done to implement property tax limitations and certain state funding programs fairly.