We’re Different

In a crowded, commoditized market with ads filling our mailboxes offering appeals for a significant percentage of your savings, we decided to break the mold.

Why Appeal?

The Cook County’s Assessor’s Office is responsible for valuing the more than 1.8 million parcels in Cook County. Is yours getting the attention it deserves?


In 2020, we lowered our customers’ assessed property values by an average of 11.7%.


On average, only 14% of single-family homes appealed their valuations.


In 2020 we were able to reduce our customers’ assessed values by over $5,255,300!

Appeal Your Taxes

What are you waiting for? Let’s get started with your appeal today!

Cook County Property Tax Appeal Service


The Residential Tax Appeal Service provides everything you need to appeal your Cook County IL property tax bill:

  • Analysis and identification of the best set of comparable properties for your appeal
  • Detailed instructions and required documents to file your appeal for the current year
  • All required information to file a Board of Review appeal if necessary

NOTE that at this time we are not able to help with appeals of apartments or condominiums.

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Assessment Calendar and Deadlines

As new filing dates are determined, they will be added below. Dates are subject to change.

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 affect 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. In between this time, your property taxes will likely go up as they always do!

When you appeal, you’re asking the county to reassess based on some type of argument as to why yours are too high.  The most common is to use a group of comparable properties as a benchmark.  If these all have lower assessments, then yours should be lower too!

The county considers this appeal, and they may or may not agree and lower your assessed value.  If they agree, great!  If they don’t, you can appeal to the Board of Review.  RTA handles both as applicable.

It is highly recommended by us (and by the Assessor’s office) that you appeal every year, whether you were reassessed automatically or not, as they truly do want to get the assessed values right.  Remember, the Assessor’s office’s job is to get assessed values of every property fairly assigned.  They do not assign the property tax multiplier, nor do they collect the taxes.  Those are done by other offices.  Their purpose is to make the assessed value for each property in Cook County fair and accurate.

Assessed values have gotten out of whack over many years, and some residents are paying far more property taxes than they should, while others may be paying far less.  By appealing each year, you’re asking the Cook County Assessor’s Office to take a look at your property’s assessed value and lower it based upon the information that our Appeal Service provides as support.

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 assist.

When should I sign up?

You can sign up whenever you want as we’ll watch the calendar for you and do our heavy lifting as soon as your township opens.  That way you don’t have to worry about missing the deadlines!

How often is my property reassessed?

Cook County is reassessed triennially, which means one-third of the county is reassessed each year. In 2020, the south suburbs will be automatically 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 or an apartment building. Can I still appeal?

Condominium and apartment 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 apartment or 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.

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 two 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 second appeal you can complete is a Board of Review appeal, which is also done via an online form and takes just a few minutes with the information and instructions we provide.

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 Board of Review appeal information and instructions.

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.

Still have a question?

Please contact us for more information and we will do our best to get back to you as quickly as possible.

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