What is equalization?

Equalization is the process of applying a multiplier to assessed values, bringing the median level of assessments of each Township or each County to 33 1/3% of the fair cash value as required by Illinois State Statute. The Chief County Assessor, the Board of Review, and the Department of Revenue have the statutory authority to equalize assessments.

Why do we equalize?

Assessments are equalized within the County to ensure they are uniform among all 24 Townships in the County. The Department of Revenue may also equalize to ensure that assessment levels are uniform between the counties in Illinois.

Chief County Assessors and/or Boards of Review equalization factors are developed and applied to each Township based on the 3 year average of median level of assessments and considering all reassessment work done in that Township by the Township Assessor, Chief County Assessor and the Board of Review. The Department of Revenue’s may also equalize, however their factor is developed by County to ensure uniform assessments among all Counties in the State.

What is the median level of assessments?

The median level of assessments is the midpoint (middle) of the range of assessments in a sales ratio study. In this case, a sales ratio study is a comparison of the selling prices of properties in the Township and its prior year’s assessed value. This gives the actual level of assessments on each property that is sold. The levels of assessments are ranked from lowest to highest and the midpoint is then identify

Example:  Prior Year Assessed Value/Sale Price = Sale Ratio
           $11,340 / $30,500 = 0.3718
           $51,830 / $143,000 = 0.3624
           $117,350 / $369,000 = 0.3180 <-- median level of assessments for group
           $16,520 / $53,000 = 0.3117
           $130,550 / $433,000 = 0.3015

How do we calculate the multiplier?

First, we calculate the median level of assessments for each Township for each of the last 3 years. We then divide 33 1/3% (statutory level of assessments) by the calculated average 3 year median level of assessments for each Township. The result is the multiplier.


   2020   2021   2022    33.33 / 3 Yr Avg    Multiplier
Helvetia  33.74  29.94  28.62    33.33 / 30.77    1.0832
Hamel  33.72  30.77  26.45    33.33 / 30.31    1.0996
Nameoki  34.63  29.74  26.39   33.33 / 30.25    1.1018

 Multipliers are then applied to all non-farms assessments in each Township for the final assessed values for the assessment year.