In Cook County, properties are classified based on their use. For example, apartment buildings over six units are classified as Class 3 properties. Class 5 properties are properties that are used for commercial or industrial purposes.

A property is used for commercial purposes if it is used primarily for buying and selling goods and services, or for otherwise providing goods and services. Commercial use includes real estate used for hotel, motel and apartment buildings of more than six units.

You may be eligible for a partial assessment if your home was uninhabitable for any part of the previous year. Uninhabitable property is a residence that due to physical condition cannot be occupied. This includes new buildings still under construction or existing buildings that are being rehabilitated.

The Assessor’s Office calculates the square footage by measuring the exterior perimeter of the home. It is that measurement that your assessment is based upon, not what you might consider to be inside “living space.”

If you feel your home is improperly assessed, you are encouraged to file an appeal with the Cook County Assessor’s Office.

The three main reasons for filing a residential appeal include:

The value of your house is based on the recent sales of properties in your neighborhood that have similar characteristics to your home (age, square footage and type of construction).