Equalization Explained

Let’s begin by asking the question “What is equalization?” In plain and simple English, equalization is bringing the median level of assessments in a township and/or a county to 33 1/3% of the fair cash value as required by Illinois law. The Supervisor of Assessments, the Board of Review, and the Department of Revenue have the statutory authority to equalize assessments.

This explanation brings with it two terms that may be unfamiliar to the reader: median level of assessments and fair cash value.

What is the median level of assessments? Simply stated, it is the midpoint or middle of the range of assessments in a sales ratio study. A sales ratio study is a comparison of the selling price of a property 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 plotted.

What is “fair cash value”? Fair cash value is defined as “the amount for which a property can be sold in the due course of business and trade, not under duress, between a willing buyer and a willing seller.”

Now you may be asking yourself why do we equalize? Assessments are equalized at the Supervisor of Assessments or Board of Review level to ensure they are uniform among the 22 townships in Whiteside County. The Department of Revenue equalizes to ensure that assessment levels are uniform between the counties in Illinois.

Supervisor of Assessments and Board of Review equalization factors are developed and applied by the township based on the 3-year median level of assessments and considering all reassessment work done in that township by the township assessor. The Department of Revenue’s equalization factor is developed by the county and applied to all non-farm properties in the county.