With the exception of Class 2 residential properties for which separate rules have been issued, the Office of the Assessor has prepared these rules to assist all Cook County property owners in pursuit of any claim of over-assessment.

Illinois law requires the Assessor to place an assessed valuation on all real property located in the county. The law also gives property owners the right to challenge the values set by the Assessor. Under the law, property owners must submit evidence sufficient to justify a reduction in assessed valuation.

Supplemental bulletins have also been prepared by the Office of the Assessor to specify the type and extent of proof which will assist in preparation of appeals for specific types of properties. These bulletins contain significant details and information which will assist in the presentation of an over-assessment claim. There are also extensive bulletins explaining eligibility requirements for the Cook County Incentives Program for certain industrial, commercial and residential properties (Classes 6b, 6c, 7a, 7b, 8 and 9 and L). These bulletins should be carefully reviewed when filing applications and appeals seeking eligibility under any of these incentives. Inquiries may be directed to the Incentives Department (312-603-7529).

So as to avoid hardship or injustice, the Assessor or his designated representative may waive any technical requirement in these rules.