If you think your property taxes are too high, you can challenge your property tax assessment.

How are property taxes figured out?

The amount of property tax you have to pay for your house is based on the value of your house. Your local assessor’s office is in charge of deciding how much your house is worth. This is called an assessment.

How do I change my property taxes? 

You can get your property taxes lowered by proving that your house is worth less than the assessor says it is.

In Cook County, you can appeal the value of your property with the Cook County Assessor. You can also appeal the value of your property to the Cook County Board of Review. The times for these appeals often have very strict deadlines depending on where your property is located. You should reach out to the Cook County Assessor’s Office and the Cook County Board of Review about when your specific property can be appealed.

Outside of Cook County in Illinois, you can contact your local assessor or chief county assessment officer about the value of your property. Some assessors may require you to file something in writing, such as a complaint form. You have to make a formal appeal about how much your house is worth to your local board of review. 

You can find contact information for your local board of review on the Illinois Property Tax Appeal Board website.

What is the deadline?

The Cook County assessor must accept appeals for 30 business days from whichever date is later:

• the date the notice is mailed, or
• the date the assessment is published on the assessor's website.

However, you may have more or less time depending on where you live. Check with your local assessor or board of review about their deadline.

Check with your local assessor or board of review about their deadline.

It may be too late to appeal your property tax assessment for this year, which is what you will pay next year. So you might not be able to do anything about the property tax you are paying this year. 

But, you can still appeal your assessment for next year, which will decide the following year’s tax. 

Your assessor or board of review can also give you the form you need to file an appeal. There is no filing fee to file an appeal.

How do I prove that my property is worth less than my assessment says it is?

Try to find records of appraisals and similar sales to show to the assessor or board of review. Since the assessor’s records are open to the public, you can compare your assessment to similar properties.

You should also carefully review the property characteristics in the assessor’s records, such as the amount of land you own and the size of your home. Mistakes in the records can often lead to wrong values for your home.

You can find more information on how to win your case on the Illinois Department of Revenue website.

How does the process work?

The board of review will meet with you, but there’s no formal hearing. The board then makes a written decision, by majority vote, based on what you present. You must pay your taxes while you appeal, but you will get a refund if you win.

What if I lose the appeal?

If you’re not happy with the board of review’s decision, you can appeal again to the Property Tax Appeal Board (PTAB). The process with the PTAB is pretty much the same, except now the board of review has to defend their decision against your evidence and arguments.

Visit the Property Tax Appeal Board website for more information on appealing a board of review’s decision.

What else can I do?

You should make sure that you are receiving all of the property tax exemptions you are entitled. Many exemptions are based on whether you live in a home or are a senior citizen or a veteran. Often, your exemptions are reflected on your property tax bill. You should contact your county assessor to determine what exemptions you are receiving and what additional exemptions you may be entitled to.