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Illinois Dept. of Revenue Releases Final 2021 Cook County Equalization Factor

Property Tax Publications

On Tuesday, the Illinois Department of Revenue released the final 2021 Cook County equalization factor.  The factor (sometimes referred to as the multiplier) for 2021 is 3.0027.  The tentative factor released in June was 2.7297 so the final factor represents a 10% increase over what the Department projected and is about 7% lower than the 2020 final factor of 3.2234.  The press release from the Department of Revenue is available here.

The equalization factor arrives as Cook County taxing districts are looking at one of the latest 2nd installment due dates in recent history, most likely the end of December. The Cook County Board of Review, which is the last stage of assessment review, just closed for the 2021 assessment cycle on October 7th – a historically late closing date.

Cook County equalization factors for the past 13 years (since 2009 when the Classification Ordinance was amended to change the levels of assessment for all classes of property to either 10% or 25%) are set forth in the table below.

Tax Year

Final Multiplier

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

2019

2.9160

2020

3.2234

2021

3.0027

 

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 being 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.