Is Cook County Overcharging You Because of Incorrect Property Records?

Property taxes in Cook County are based on the assessed value of your home. That value comes from the information the Cook County Assessor’s Office has about your property. But what happens when that information is wrong? Incorrect records can include errors in square footage, number of bedrooms or bathrooms, property type, or even lot size. When these characteristics are inaccurate, your property may be overvalued, which means you’re paying more in property taxes than you should.

Understanding how to spot these errors and take action is essential for protecting your investment. This blog explains what to do if your property’s characteristics are wrong and how a Cook County Property Tax Attorney can help you fix them.

The Most Common Errors That Cost Homeowners Money

The Assessor’s Office relies on property records, field inspections, and sales data to determine property characteristics. However, mistakes happen more often than you might think. Common errors include:

• Incorrect square footage of your building or lot
• Misclassified property type (for example, a single-family home listed as a two-flat)
• Added structures that don’t exist, like garages or sheds you never built
• Wrong building age or condition information
• Incorrect property classification codes

Even small errors can have a big impact on your assessed value. For instance, an extra 200 square feet listed in the records could increase your taxes by hundreds or even thousands of dollars per year. Over time, these overpayments add up significantly.

How to Correct Errors in Your Property Records

If you notice mistakes in the Assessor’s records, follow these steps:

Gather Your Documentation

Collect evidence that supports the correct characteristics of your property. This may include:

• Original blueprints or building plans
• Survey reports showing lot dimensions
• Recent appraisal reports
• Photographs of your property
• Building permits that show actual square footage
• Floor plans
• Contractor invoices for work completed

The more documentation you have, the stronger your case will be.

Contact the Assessor’s Office

The Cook County Assessor encourages homeowners to report factual errors in property characteristics. You can contact them directly to request a correction, even outside of the regular appeal period. Provide your documentation and clearly explain the errors. The Assessor may review your evidence and adjust the records.

You can also use the Assessor’s online “Update Property Characteristics” form if available for your township.

File an Appeal if Needed

If the Assessor doesn’t correct the error through the simple correction process, you can file a formal appeal. You have two opportunities to appeal:

1. Assessor’s Office Appeal during your township’s reassessment year
2. Board of Review Appeal if the Assessor denies your request

Appeals must be filed within specific deadlines based on your township’s reassessment schedule. The appeal process allows you to present your evidence and argue for a lower assessment based on the accurate characteristics of your property.  Note, that the Board of Review cannot update the Assessor characteristics (ex. square footages). Only the Assessor can update the Assessor records. However, the Board of Review can use the correct characteristics to give you a proper valuation.

Consider a Certificate of Error

If you discover errors after the appeal period has closed or after your tax bill has been issued, you can file a certificate of error. This process allows corrections to be made for prior tax years. If approved, you may receive a refund or adjusted bill for overpaid taxes.

Certificate of error applications require supporting documentation and can be filed online or by mail to the Assessor’s Office.

How Professional Help Makes a Difference

Filing corrections, appeals, and certificate of error applications can be complex. A property tax attorney can help you navigate the process and improve your chances of success. An attorney can:

• Review your assessment and identify all errors in property characteristics
• Determine the best correction method (simple update, appeal, or certificate of error)
• Gather and organize necessary documentation
• Prepare a detailed filing that addresses each error
• Ensure your request is filed by the deadline
• Communicate with the Assessor’s Office and Board of Review on your behalf
• Represent you at hearings if needed
• Follow up to make sure corrections are properly applied

Professional guidance helps you avoid common mistakes that can lead to denied requests.

Protect Your Financial Future

Correcting errors in your property’s characteristics can save you money immediately and prevent future overpayments. Overvalued properties may also affect your home’s resale value or make refinancing more expensive. Taking action promptly ensures your assessment reflects the true value of your property.

Many Cook County homeowners have no idea their property records contain errors. A simple review of your assessment notice could reveal mistakes that have been costing you money for years. Don’t assume the Assessor’s records are correct just because they’re official government records. Errors happen, and it’s your right to have them corrected.

If you suspect errors in your Cook County property records, Aaron Fox Law can help. The firm provides guidance to homeowners reviewing assessments, filing corrections, and appealing inaccurate valuations. With experience in Cook County property tax matters and over one thousand successful appeals, you have nothing to lose by getting a professional review.

To learn more or schedule a free consultation, visit Aaron Fox Law’s property tax page.

Correcting property record errors protects your financial interests and ensures you pay only what’s fair. Don’t let simple mistakes cost you thousands of dollars over the years you own your home.