Due to a Countywide technology upgrade, processing of Certificates of Error applications are temporarily on hold. This means that no applications or refunds will be issued at this time. Applications can still be filed, but they will be processed at a later date in the order they were received. When your application is processed, you will receive an email notification with the result. You can also check the status of your application by logging into your account and clicking on “My Filings” on the top of the Page. Login here
Holiday Observance Closure
In observance of the holiday, our offices will close at 2PM on Thursday, July 3, 2025. We will resume normal operations on Monday, July 7, 2025. Most of our services are available online. Visit our website at cookcountyassessor.com.
The Cook County Assessor’s Office is committed to sharing data about your community. You can find our data releases here, as well as tools you can use to better understand property assessments and their role in Cook County’s property tax system.
Assessment Data
You can download the characteristics data used to estimate the values of Cook County homes.