In Cook County, your Class 2 residential property is assessed at 10 percent of its estimated property value. The estimated property value is determined by analyzing sales information of similar homes in your area. For example, an estimated property value of $100,000 would calculate to an assessed valuation of $10,000. Class 2 properties include detached single-family houses, townhomes, condominiums, cooperatives, and multi-family residential buildings with no more than six dwelling units. (Separate instructions are available for condominiums and cooperatives.)

Keep in mind, the Assessor does not calculate taxes. Local governments, such as municipalities and school districts, determine the overall amount of real estate taxes collected in your community. It is important that your assessed valuation be accurate and fair, as it does play a role in determining your share of those taxes.

It is the policy of the Cook County Assessor to assess all real property in a fair and uniform manner consistent with the legal responsibility placed on the Office of the Assessor. It is also our policy to provide everyone equal access to the remedies afforded by the appeal process. In accordance with these policies, the Office of the Assessor shall provide experienced personnel to assist property owners who want to appeal their assessed valuations.

You will receive a "Notice of Proposed Assessed Valuation" in the mail when the Assessor's Office reassesses your home every three years. This notice includes an estimate of the proposed property value and the proposed assessed valuation. The notice also includes a list of characteristics that are relevant to your home's property value.

Once you have received your "Notice of Proposed Assessed Valuation", you have approximately 30 calendar days to file an appeal with our office. The last date to file an appeal is printed on the top of your notice. You may also appeal your assessed valuation in any year between reassessments.

To file an appeal online, find your property via our Property Search. If you cannot file an appeal online, prefer to visit one of our offices, or want to mail your appeal, you must use an official "Real Estate Assessed Valuation Appealform. Please submit one copy and keep another copy for your files. You do not need a lawyer, tax representative or appraiser to file an appeal on the assessed valuation of your home. However, if your valuation appeal is filed by your authorized representative, an "Owner/Lessee Verification Formmust be completed, notarized and filed along with the appeal form.

Three common grounds for appeals are listed below:

1. Uniformity Appeal:

   If you are concerned that the assessed valuation of your home is not uniform with the assessed valuations of other homes, compare your property to similar homes. This comparison will tell you if you have reason to file a uniformity appeal.

   There are two ways to do this:

   1. Simply fill out the appeal form, indicating that the purpose of the appeal is "lack of uniformity". You do not need to research and find your own comparable properties in order to file an appeal with our office. Our analysts will check properties comparable to yours to determine if your assessed value is in line with the assessed values of those properties.
   2. If you wish to include a list of comparable properties with your appeal, please follow the gudielines below:
      • For your convenience, all residential assessments will be published in a local community newspaper a few days after you receive your reassessment notice. The name of the newspaper and date of publication are indicated on your notice. The assessment listing will also be available at your local library.
      • When choosing comparable properties, select homes within your neighborhood code that closely resemble your own home in both size and style. If the Permanent Index Numbers (PINs) are not known, the Assessor's staff will assist you in obtaining this information. You may also use the residential data books located in all of our offices to check if the comparable assessed values are in line with your assessment. If the assessed value of the comparable properties that you have chosen are lower than your assessed value, you may have reason to file an appeal.
      • You may also find the assessed values of comparable properties by visiting the assessor's Web site property search. Pictures of nearly every Cook County property may also be found there.
      • Write the PINs that you have found to be comparable on the appeal form that you file. Our analysts will use your information, along with our office data, to determine if the assessed value of your home is in line with the assessed values of comparable properties.

2. Overvaluation Appeal:

   You may also wish to file an appeal if you believe our estimate of the property value is overvalued for any reason. You are encouraged to submit supporting documentation, such as recent closing statements or purchase prices of homes similar to yours, along with your appeal.

3. Property Description Error Appeal:

   Finally, if there is an error in the description of your property, such as incorrect square footage of living area or an error that you believe may affect property value, you may wish to file an appeal. However, a minor error does not necessarily indicate an incorrect assessment.

To file an appeal now, use the Property Searchon this Web site and click on Appeals. Once there, complete the information and file the appeal. If you do not see a form at this point then that means your township is not open to submit appeals. You may also file an appeal at our office, your local township office, or you may request that an appeal form be mailed to you. Experienced personnel are available at all of our offices to help you in filing your appeal. Please have your "Notice of Proposed Assessed Valuationhandy because it contains important information.

After your appeal is filed, the Assessor's Office will analyze your information and mail you the result of your appeal.

To make sure you receive the best service possible, a Taxpayer Advocate is available to re-review your appeal results and answer any questions you may have. The Taxpayer Advocate is located in the main office of the Cook County Assessor. The Taxpayer Advocate's telephone number is 312-603-7530. If you wish to further pursue the appeal of your assessment, you may also file an appeal with the Cook County Board of Review (312-603-5542).

Residential property owners who experience severe damage to their homes as a result of a catastrophic event are eligible to receive a home improvement exemption of up to $75,000.

This exemption is available when a residential structure is rebuilt after a catastrophic event. The exemption applies to the difference between the increased value of the rebuilt structure and the value of the structure before the catastrophic event.

The residential structure must be rebuilt within two years after the catastrophic event. The exemption will continue for four years following completion or until the next reassessment, whichever is later.

Catastrophic events are defined as severe damage or loss of property resulting from any catastrophic cause including but not limited to fire, flood, earthquake, wind, storm, explosion or extended periods of severe inclement weather. In the case of flooding, the structure must be located within a jurisdiction which is participating in the National Flood Insurance Program.

To file for a Catastrophic Event Exemption, the property owner or authorized representative must complete a Residential Assessed Valuation Appeal form.

Along with the appeal form, it is necessary to submit the following materials:

1. a written description of the damages and the dates when damages occurred,
2. the estimated date of completion for repairs or rebuilding, and
3. all pertinent records such as photographs, insurance reports, building permits and occupancy certificates.

Appeal forms and documentation may be filed by mail or in person.

An appeal may only be filed while the Assessor?s Office is accepting appeals for your township.

• Download Sample Residential Notice