2018 Cook County Tentative Multiplier Announced

2/7/2019

SPRINGFIELD, IL - A tentative 2018 property tax equalization factor of 2.8366 for Cook County was announced today by the Illinois Department of Revenue.

The Department is required by law to calculate the factor, often called the multiplier, to achieve uniform property assessment throughout the state.

The 2018 tentative equalization factor decreased from the 2017 final factor of 2.9627

The Department determines the equalization factor for each county by comparing the actual selling price of individual properties sold over a three year period to the assessed value placed on those properties by the county assessor. If the median level of assessment for all property in the county varies from the 33 1/3 percent level required by law, an equalization factor is assigned to bring assessments to the legally mandated level.

The three-year average level of assessments (weighted by class) for Cook County property is 11.75 percent. The Department calculated the multiplier to bring the average level of assessments to the required 33 1/3 percent level by dividing Cook County's three-year average of 11.75 into 33.33.

After taking into account the 2018 reassessments, the levels of assessment are as follows:

​Class
​2015
​2016
​2017
​3-Year Average
1  (Vacant Lots)
​6.60
​7.01
​6.51
​6.71
​​2  (Residential)
​10.19
​9.58
​9.14
​9.64
​​3  (Apartments)
​7.46
​8.72
​7.88
​8.02
5a (Commercial)
​25.58
​22.62
​22.18
​23.46
​5b (Industrial)
​24.32
​20.44
​20.76
​21.84
​County Wide
(Weighted average)
​12.38
​11.68
​11.19
​11.75

The equalization factor does not cause individual tax bills to go up. Tax bills are determined by local taxing bodies when they request the dollars needed to provide services to citizens. The assessment process simply determines how the bill will be divided among taxpayers.

A Cook County ordinance requires that residential property (homes, condominiums, apartment buildings of six units or less) be assessed at 10 percent of market value; all other residential property (apartments with more than six units), 10 percent; vacant lots, 10 percent; property owned by not-for-profit corporations, 25 percent; commercial property, 25 percent; industrial property, 25 percent; and commercial or industrial property being developed in economically deprived areas, usually 10 percent.

PDF 2018 Cook County Tentative Multiplier Announced