Certificates of Error Filings for Valuations

At this time, we do not have a projected time for processing Certificates of Error related to property valuation, but rest assured our team is working to process them as soon as possible. If your Certificate of Error for valuation corrections has been approved and you are waiting for a refund, please check with the Cook County Treasurer’s Office for updates on timing of refunds. At this time, valuation Certificates of Error are not being refunded. Check this alert banner for regular updates.

Holiday Observance

In observance of Casimir Pulaski Day our offices will be closed Monday, March 2, 2026. We will resume normal operations on Tuesday, March 3, 2026.

Markham Branch Office Closure

Effective Monday, September 22, 2025, the Cook County Assessor’s Office located inside the Markham Courthouse will be closed for remodeling until further notice. For appointments or assistance, please visit our website to book at a nearby branch.