Taxes

Lack of Uniformity vs. Overvaluation: The Two Ways to Win a Cook County Property Tax Appeal

Cook County property tax appeals succeed on one of two legal theories: lack of uniformity or overvaluation. Here is what each one means, what evidence each requires, and when to use which.

Cook County property assessment appeal records and comparable properties

Cook County property tax appeals win on one of two legal theories, and knowing which one fits your property determines what evidence you gather and how you argue. The first theory is lack of uniformity, which argues that your property is assessed higher than comparable properties. The second is overvaluation, which argues that the Assessor's estimate of your property's market value is simply too high. They are different arguments, they rely on different evidence, and the strongest appeals often use both.

Lack of uniformity

The uniformity argument rests on a principle of fairness: similar properties should be assessed similarly. If comparable homes near yours, matched for size, age, style, lot, and condition, are assessed for less than yours, your assessment lacks uniformity and should be reduced to match. This is the workhorse argument for residential appeals, especially in areas with consistent housing stock like Chicago's bungalow belt or blocks of similar suburban homes.

The evidence is a set of comparable properties and their assessments. The skill lies in selecting genuinely comparable properties, because the Assessor and the Board of Review will scrutinize whether the comparables truly match. Comparables that are similar in the characteristics that drive value, and that are assessed for less, make the case.

Overvaluation

The overvaluation argument rests on market value: the Assessor's job is to estimate what your property would sell for, and if that estimate is too high, the assessment should come down regardless of how neighbors are assessed. The evidence is market data, primarily recent sales of comparable properties, and sometimes a recent sale of the property itself or an appraisal.

Overvaluation is often the stronger argument for commercial and income-producing property, where the income approach shows that the property cannot produce enough to justify the assessed value. It is also powerful for any property in a declining market, or any property recently purchased for less than its assessed market value implies.

Using both

The strongest appeals frequently combine the two. A residential appeal might lead with uniformity, showing comparable homes assessed for less, and support it with sales data showing the market value is also too high. A commercial appeal might lead with the income approach and overvaluation, and add uniformity by comparing to similar commercial properties. Presenting both gives the Assessor and the Board of Review more than one path to the same reduction.

When to call a Chicago property tax attorney

Choosing the right theory, and assembling evidence that holds up, is what separates a successful appeal from a denied one. Younis Law Group builds uniformity and overvaluation arguments for residential, commercial, and income property across Cook County, selecting the theory and the evidence that fit each property. If you are considering an appeal and are not sure how to argue it, reach out for a review.

For representation at the county's available review stages, see Younis Law Group's Cook County property tax appeal service.

Author

Omar Younis

Managing Partner

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