Suggestions and Tips

The Commissioners and the entire staff of the Board of Review want to express their welcome to taxpayers seeking to appeal their Cook County property taxes.

The B.O.R. staff is ready to aid you in assembling an effective appeal that will address your complaints. The Board also provides outstanding taxpayer assistance. They personally review each and every appeal filed and assess the needs of individual taxpayers and their property.

Please do not hesitate to ask a B.O.R. staff member any questions you may have about the property tax appeal process or your complaint. No question will go unanswered and no appeal ignored!

This Web Site is your newest tool in the property tax appeal arsenal. Here you will find a collection of information at your fingertips. It's the easiest and most convenient way to pre-register for forms and gather information.

How To Appeal Your Assessment

1. Determine the time frame for your appeal and/or pre-register for forms

Your complaint must be filed within the 30-day appeal period designated each year for the township in which your property is located. These appeal periods vary based upon the township and are not established in advance. The best way to guarantee your notification is to pre-register for forms and information by sending us an email with the following information: your name, address, permanent index number* and township.

A B.O.R. staff member will mail you the Board Complaint form when your township opens.

*Your Permanent Index Number, or PIN, is the 14 digit number separated by hyphens that identifies your parcel from the other 1.8 million in Cook County. You can find this on your tax bill or on any correspondence you receive from the Assessor. You can also find your PIN by searching the Assessor’s Site with your address Be sure to scroll down to the bottom of the Web page to use the address search feature.

2. Determine the type of property you own

Property in Cook County is assessed based upon the type of property. Small residential properties, which include homes, condominiums, apartment buildings of 6 units or less, and certain mixed-use (small stores with apartments above, or commercial/residential) properties under 20,000 square feet, are all assessed at 10% of market value. This means that the value noted on your assessment represents 10% of what the Cook County Assessor believes your property to be worth. (for more information see

Homeowners and owners of property falling into this category can choose to represent themselves, enlist the help of B.O.R. staff members, or hire an attorney. Corporations must be represented by an attorney and should look at the “Offical Rules of the Board of Review”. See B.O.R. Rule # 1

Owners of other properties should consult the pamphlet entitled “Official Rules of the Board of Review”. These properties include the following:

  1. Vacant land – assessed at 10% of market value
  2. Not-for-profit realty – assessed at 25% of market value
  3. Apartment buildings with 7 or more units – assessed at 13% of market value
  4. Industrial business properties - assessed at 25% of market value
  5. Commercial business properties – assessed at 25% of market value
  6. Incentive classes are at various percentages

If you have any questions about the classification of your property, please do not hesitate to call the Board of Review at 312-603-5542.

3. Determine the Grounds for Your Appeal

There are several grounds for an appeal. The following are a few of them:

  1. Your neighbors or other properties in the immediate area are assessed much lower than your property. You can check this by looking up addresses or PINs on .
  2. Your assessment has a major factual error or a mathematical error in computing the assessment that affects the value placed on it by the Assessor.
  3. Your property has been damaged by fire, flood, or other catastrophe and/or part of the building has been demolished.
  4. You recently purchased your property for less than the value placed on the property by the Assessor.

Please call the B.O.R. if you have any questions about your property or need help determining if your property falls into one of these categories.

4. Assemble Your Appeal

Fill out the complaint form and return it to the B.O.R.. Even if you do not have your evidence completed, this form will allow us to inform you by mail of your hearing date. You will then have time to assemble your appeal.

5. Gather your evidence.

If you are appealing because other properties in your area are assessed at lower values than your property, or a “lack of uniformity” appeal, you will need to find lower “comparables”.

  1. Select several properties in your neighborhood that have the same classification, meaning that they are a similar size, construction, age and style. You should gather about 4 or 5 comparable properties. Comparable properties can be found in the Board of Review offices on microfiche and on the Cook County Assessor’s Web Site at
  2. The Board of Review will send you a summary sheet or you can download one here The summary sheet has a space to place the required picture of your property, the “subject property” and information on its assessed value. Below the subject property, you will place pictures of your comparable properties (taken on your own or printable from the Assessor’s Web Site and their corresponding PINs and assessed valuation information. The PINs can be found by searching the Assessor’s Web Site at, at the Office of the Cook County Treasurer, 118 North Clark Street, 1st Floor, Chicago, IL 60602, at your local township assessor, or in any of our satellite offices.
  3. Your evidence must be returned on or before the day of your hearing.

The Board of Review staff will assist you in finding PINs or comparable properties.
Please call 312-603-5542.

If you are appealing based on a major factual error in a single family home or small
apartment building, you can request a property information sheet from the B.O.R.
as soon as your township opens. You can read over the information on file for your property
and call any errors to our attention by filling out an affidavit. You can download
this form at
or you can get one from our office.

If you are appealing based upon an error made by the Assessor in determining the size of your lot or the number of square feet of living area in your property, you will need a supporting plat of survey, plan or equivalent substantiation prepared by an architect, surveyor, builder or engineer

If your property has been damaged by fire, flood or other catastrophe, your claim should be supported by documentation.

  1. In the case of a fire, a fire department report should accompany your appeal.
  2. If your property has been demolished, a demolition permit will need to be provided to the Board.
  3. Evidence of flooding should be provided by copies of an insurance claim form and proof of subsequent payment, newspaper reports, copies of requests for government loan assistance and estimates and bills for repairs.

Pictures are very helpful to the Board in the above cases to illustrate the extent of damage or show vacant property after demolition. On their reverse side, please write the PIN and date pictures were taken. Note: Submitted photographs remain a permanent part of your file.

Appeals based on recent purchases (1/1/2011 or later), should be accompanied by a copy of the closing statement, a copy of the real estate contract, and any other information you would want the Board to consider in reviewing your appeal.

The Board of Review staff will assist you in any way possible to assemble an effective appeal based on the above reasons or other issues you feel need to be addressed regarding your property assessment.

Senior citizens, or those age 65 or older as of December 31st 1, 2012, residing in single-family homes or small apartment buildings may be entitled to a senior citizen tax exemption as well as your homeowner’s exemption. You can check online to see if you are receiving these benefits or apply for them at A B.O. R. staff member can help you get the proper forms if you do not have access to a printer.