Frequently Asked Questions

If it’s on your mind, others have probably also inquired. Here are the most commonly asked questions we receive and useful information from the Cook County Assessor’s website.

Why should I appeal?

The reality is that less than 20% of homeowners appeal their property taxes. They may feel that their bill shows an appropriate (or even lower) fair market value for their home’s worth. “Maybe we’re already getting a great deal!”

Others feel that the information on their bill is incorrectly stated, and appealing will trigger someone to come out and take a look.  For example, you have a finished basement but the tax bill indicates unfinished. Unfortunately this logic does not hold true. Basements do not effect your property tax bill in most counties as they are not included in your square footage. Whether finished or unfinished, it doesn’t matter.

The Cook County’s Assessor’s Office is responsible for valuing the more than 1.8 million parcels in Cook County. Each township is automatically reassessed once every three years.

By appealing each year, you are asking the county to consider reducing your assessment regardless of when it was last valued, and therefore it makes sense to appeal each year. Your appeal can only result in a reduction in your assessed value, or no change. Appeals WILL NEVER result in any increase to your property’s assessed value.

Can’t I just do this myself?

Absolutely.  For example, the Cook County Assessor’s website provides everything you need to file on your own. Property tax information is public record.

The question you need to consider is “Do I want to spend the time to learn the process, search for comparables, identify the best candidates to use, and file the appeal?“. If you have the time and desire, by all means go for it. Many people do. If you would rather have help at an affordable price and spend just a few minutes of your time, we’re here to help.

How often is my property reassessed?

Cook County is reassessed triennially, which means one-third of the county is reassessed each year. This year, the south suburbs will be reassessed. The City of Chicago will be reassessed in 2021. The northern suburbs will be reassessed in 2022. Your property may also be reassessed if there are significant changes due to a permit application, property division, demolition, or other special application.

Do I need a lawyer to file an appeal?

NO, you do not need an attorney to file your property tax appeal. In fact, according to an ABC 7 I-Team report:

  • most homeowners appealing to the Assessor’s Office do not use an attorney, and
  • most successful appeals to the Assessor’s Office did not use an attorney.

In Cook County, the law allows property tax services like ours to have the same access that lawyers have to the public records and required documentation. In fact, the Cook County website has made a lot of improvements over the years to help residents compile the necessary information on their own.  The Assessor’s office will also help you for free if you have the time to hang out with them for a few hours.

I live in a condo. Can I still appeal?

Condominium owner’s property taxes are based on the valuation of the building or condo association. At this time, RTA does not have the ability to help condo owners with their appeal.

Which Property Classifications does the RTA property tax appeal service support?

There are over a dozen classifications of properties in Cook County, including commercial, residential and industrial. At this time, RTA supports most residential classes that fall under the category Major Class 2 Residential. This includes classes 2-02 through 2-11, 2-34 and 2-78.

At this time we are not able to support apartments, condominiums, commercial or industrial properties. This may change in the future.

A full list of Classifications can be located at

How long does the appeal process take?

Residential Tax Appeal leverages technology and expertise to do all the heavy lifting for you. Once you sign up, we get to work.

There are three opportunities that we offer to save you money.

  • The initial appeal is an online form and takes just a few minutes with the information and instructions we provide.
  • The re-review has historically been a one page PDF document that you complete with the information we provide, and then hand-deliver, mail or fax. With the revised process and Cook County Assessor’s website, we will update this FAQ as soon as the re-review process has been announced.
  • The third appeal you can complete is a Board of Review appeal, which similar to the re-review appeal has been a PDF document that you complete with our provided instructions and information. We are not yet certain as to the Board of Review process for 2020 and will update this FAQ as soon as the re-review process has been announced

All in all, you will spend on average under an hour of your time to potentially save hundreds or thousands of dollars!  Not bad, huh?

If I appeal and am not successful, will my assessed value go up?

If you file an appeal and are not successful, your assessed value will NOT go up. It stays the same for the three years between triennials unless you appeal the following year and win (which we hope you will).

Keep in mind that with RTA, if your appeal is not successful, we will also complete the necessary information for the re-review appeal and if applicable, the Board of Review appeal.

The Cook County Board of Review is an independently-elected, quasi-judicial body and by law can take into consideration factors the Assessor’s Office is not allowed to use.

If my assessment increases, does that mean that my tax bill will increase?

Not necessarily. The assessed value of your property is only one factor in determining your property taxes. Your total tax levy, set by local taxing bodies like schools, is an important factor in setting your tax rate.

Your property’s assessed value, tax rate, and exemptions will be used to calculate the second installment of the property tax bill you receive the following year. Property tax bills are sent by the Cook County Treasurer.

When will I see my savings?

Your annual tax bill comes from the County Treasurer’s Office in two installments: one is due in February and the other is due in August.

Your reassessment will affect the second installment tax bill the following year. So if your reassessment notice arrives in 2020, the tax bill reflecting this assessment will arrive in July of 2021. Any appeals of your reassessment value will be reflected in the second installment tax bill the following year.

Cook County residents get reassessed every three years.  If you file for a permit or buy a new home, it may occur sooner.  Depending on where you are in the three year period, your savings can be realized for up to three years.

That means that if you are in a reassessment year and you appeal, your savings will benefit you each of the next three years! If you are due for reassessment next year, your appeal this year will save you for one year until the reassessment is done.

NOTE that you can and should appeal each year, regardless of whether or not it is a reassessment year. Saving last year does not mean you can’t save again this year.