The Pre-Registration process in Cook County lets property owners sign up early.
They can do this before the property tax appeal filing period opens.
It is available through both:
Cook County Assessor’s Office
Cook County Board of Review
Why Pre-Registration Exists
Each township in Cook County has a limited appeal window. Once the filing period opens, many property owners try to submit appeals at the same time.
Pre-Registration helps:
Save time during the official filing window
Allow property owners to prepare early
Ensure you are ready to file once the appeal period opens
It does not mean your appeal is filed. It only prepares your account and property information in advance.
How the Pre-Registration Process Works
Step 1: Sign Up Before the Appeal Window Opens
Before your township’s appeal period begins, you can:
Log into the Assessor or Board of Review portal
Enter your Property Index Number (PIN)
Confirm property details
Create or update your online account
Step 2: Prepare Your Appeal Information
You can:
Review your assessed value
Gather supporting documents such as comparable sales or income statements
Prepare your appeal argument
Step 3: File When the Window Opens
Once the official appeal period opens for your township:
You must submit the appeal formally
Pre-Registration does not automatically file your appeal
You still must complete and submit the required forms