How Cook County Property Tax Reassessments Work: A Complete Guide for Property Owners

If you own property in Cook County, understanding how property assessments work can save you thousands of dollars. The Cook County Assessor’s Office uses a three-year cycle to review property values. This means your property gets a fresh look every three years to make sure its value matches what similar homes are selling for.

The Three-Year Reassessment Cycle

Cook County divides all properties into three groups. Each year, one group gets reassessed. This system helps the Assessor’s Office handle the huge number of properties in the county while keeping values current with market changes.

How the Cycle Works

The reassessment schedule follows a predictable pattern that helps property owners plan ahead:

• South and West Suburbs: These townships are reassessed in the first year of each three-year cycle
• City of Chicago: All Chicago properties are reassessed in the second year
• North Suburbs: These townships are reassessed in the third year, then the cycle starts over

When it’s your area’s turn for reassessment, you’ll receive a Reassessment Notice showing your property’s estimated market value based on recent sales in your area and other factors that affect property values.

This regular schedule means you always know when your property will be reassessed next.

When Properties Get Reassessed Outside the Normal Cycle

Sometimes properties need to be reassessed before their scheduled year. These “off-cycle” reassessments happen when:

New Construction or Major Improvements If you add a room, build a deck, or make other big improvements to your property, it may get reassessed to reflect the higher value. This includes getting permits for major renovations.

Property Changes When land gets divided into separate lots, each new piece needs its own assessment. If a building gets torn down, the property value needs to be adjusted too.

Permit Applications
Major changes that require building permits can trigger a new assessment. The county wants to make sure the assessment reflects the current condition of your property.

These off-cycle reassessments help keep property values accurate between the regular three-year reviews.

Your Right to Appeal Your Assessment

If the property characteristics listed on your assessment notice are incorrect, or if the estimated market value of your home is significantly more than what you believe your home could sell for in the current real estate market, you should file an appeal.

When to Consider an Appeal

A good rule of thumb is this: If the property characteristics on this notice are correct and the estimated market value is within 10 percent of what you think your home is worth then it is unlikely that an appeal would change your property’s assessed value enough to significantly affect its property tax bill. However, even if your assessment falls within this range, you may still have grounds for an appeal if your assessment is higher than similar neighboring properties.

You should think about appealing if:

• Your property details are wrong (wrong square footage, number of rooms, etc.)
• Your estimated market value seems too high compared to similar homes
• Your assessment is higher than comparable neighboring properties, even if it’s within 10% of market value
• Your property has problems that lower its value (like major damage or massive repairs)
• Recent sales in your neighborhood were much lower than your assessment

Important Appeal Deadlines

Typically, you have 45 days to file an appeal after receiving your reassessment notice. The last date to file an appeal for that year is printed on your notice. Missing this deadline means waiting until next year when your township opens for appeals again.

When your area is scheduled for reassessment, property owners will have a specific window to file appeals. Mark your calendar as soon as you get your notice.

Understanding Your Assessment vs. Your Tax Bill

Many property owners get confused about how assessments affect their actual tax bills. An increase (or decrease) in your home’s assessment does not lead to the same increase (or decrease) in your property taxes.

Here’s what really matters:

• Your property’s share compared to all other properties in your area
• The total amount of taxes your local governments need to collect
• Any exemptions you qualify for (like homeowner’s exemption)

Your property’s share of the total assessed value of all properties within your community affects your share of your community’s property taxes. This means even if your assessment goes up, your taxes might stay the same or even go down if other properties in your area went up more.

How Changes Show Up in Your Tax Bill

Changes in your tax bill due to changes in assessments or local levies will be reflected in your second installment tax bill the year following your reassessment. For instance, if you’re reassessed this year, the changes will affect your property tax bill next summer.

Building Your Appeal Case

If you decide to appeal, you’ll need evidence to support your case. The strongest evidence includes:

Recent Sales Data Look for homes similar to yours that sold recently for less than your estimated market value. The best comparisons are houses in your neighborhood that sold within the past year.

Assessment Data

Compare your assessment to similar properties in your area. If neighboring homes with comparable features (similar size, age, condition, and location) are assessed at lower values than yours, this can be strong evidence for your appeal. You can research assessment data for comparable properties through the Cook County Assessor’s website.

Property Condition Issues
Document any problems that affect your home’s value, like:

• Needed major repairs
• Damage from storms or other causes
• Unusual lot characteristics

Photos and Documentation All appraisals submitted in support of an appeal must include an original, color, date stamped photograph of the front of the subject property. Take photos that show your property’s condition and any issues that might lower its value.

Why Professional Help Makes Sense

You do not need to hire anyone to file an appeal for you. But that doesn’t mean you should go it alone. Many property owners find that working with a Cook County property tax attorney gives them peace of mind. Property tax appeals involve complex legal and valuation issues. An experienced attorney who focuses on Cook County property taxes brings several advantages:

• Deep knowledge of local assessment practices
• Experience with successful appeal strategies
• Understanding of what evidence works best
• Ability to navigate the system efficiently

At Aaron Fox Law, we focus on Cook County property tax issues. We understand the local system and have a track record of helping property owners reduce their tax burden.

Common Questions About Reassessments

I recently purchased my home. Why is the assessment different from what I paid?

A home’s recent purchase price is sometimes, but not always, a reflection of its true market value. Sale prices depend on not just the characteristics of the home itself, but also the individual buyer, seller, and even the time of year. To be fair to all properties, (those that have sold recently and those that haven’t), the Cook County Assessor’s Office uses the same methods to estimate true market values for all properties.

Can I appeal my assessment every year?

You can appeal your property taxes every year to make sure you’re paying only your fair share. However, once you’ve successfully appealed your reassessment, you likely won’t see major reductions year after year. Still, it’s often worth appealing — especially if nearby properties are assessed lower than yours.

What’s the difference between estimated market value and assessed value?

The estimated market value is what the Assessor’s Office believes properties like yours are worth in the current real estate market. The assessed value is the amount used to calculate your property taxes. For residential property, this is usually 10% of the estimated market value. For commercial property, this is typically 25% of estimated market value.

Don’t Wait Until It’s Too Late

Property tax reassessments affect your finances for years to come. When you receive a Reassessment Notice, don’t just file it away. Review it carefully and consider whether an appeal makes sense for your situation.

Remember, you only get one chance per reassessment cycle. Missing your appeal deadline means waiting three more years for another opportunity through the regular process.

Get Legal Help with Your Property Tax Appeal

If you’re facing a reassessment in Cook County, now is the time to act. The experienced team at Aaron Fox Law can evaluate your situation and help you understand your options.

We offer a free consultation to review your reassessment notice and discuss whether an appeal could save you money. Our fee structure means you only pay if we successfully reduce your assessment.

Don’t let an unfair assessment cost you thousands in unnecessary property taxes. Contact Aaron Fox Law today to protect your interests and ensure you’re paying only your fair share.