How to appeal a Cook County property assessment
An appeal asks Cook County to review whether the property record or assessed value is correct. Filing is free, and a homeowner can file without hiring an attorney.
Start by checking how your home compares.
Enter a Cook County address or property PIN.
Free to check first. No credit card required.
First, understand the number on your notice
Assessed value is the County’s tax value, not the expected sale price. For most Class 2 residential property, assessed value is 10% of estimated market value.
Approximately $560,000 estimated market value before later tax-bill calculations.
Common reasons to request a review
- The County record lists incorrect property characteristics.
- The estimated market value appears higher than the home could reasonably sell for.
- Similar nearby homes have lower assessments—a lack-of-uniformity argument.
Prepare a small, coherent evidence set
Useful comparable properties are generally close by and similar in residential class, building size, age, lot size, and major features. The comparison should explain why another home is genuinely similar—not merely why its number is lower.
Learn how to evaluate comparable properties →Choose the correct filing path
The Cook County Assessor and Board of Review use separate filing systems and township-specific windows. The Assessor says appeal periods are typically limited; the Board does not accept complaints after the official township closing date.
Compare the Assessor and Board of Review →Official filing resources
See whether lower-assessed similar homes exist.
Simple Tax Appeal provides public-record research and filing preparation. It does not file an appeal, provide legal representation, or promise a particular government decision.