On May 6, the Cook County Assessor’s Office mailed reassessment notices to all Oak Park property owners, which reflect the assessor’s estimate of the value of all Oak Park properties as of Jan. 1, 2026. Unless reduced by appeal, the new values will be used to determine the taxes on each Oak Park property between 2027 and 2029.
Can I appeal the assessed value proposed by the Cook County Assessor’s Office?
Yes. Taxpayers can appeal their new assessed values through June 18, and the Oak Park Township Assessor’s office is available to help. If you want assistance from my office in filing an appeal, you should call the Township at 708-383-8005 to set up an appointment.
What is an assessment appeal, and what is the basis for filing one? Assessment appeals seek to reduce a property’s assessed valuation by claiming that its assessment is unfair or inaccurate. There are three basic grounds for filing an appeal:
1. Comparable properties assessed for less. If you find properties similar to yours that are assessed for less, you can seek to reduce your assessment to the level of the comparable properties. My office can help you find comparable properties quickly and easily.
2. Errors in property characteristics. Each house has a set of characteristics that help determine its assessed value, and errors in those characteristics can be appealed. The type of error most likely to result in a lower assessment is an overstatement of the square footage of your house.
3. Recent purchase or appraisal. If the market value set by the Cook County Assessor is higher than a recent purchase price or recent appraisal for your property, an appeal may be successful.
If my assessed value increased by 25%, will my taxes increase by 25%?
No. It is virtually certain that any tax increase you experience as a result of the reassessment will be less than the increase in your assessed value.
A deeper dive into the above question, however, reveals that a reassessment can result in great variation in tax changes for members of a community, as was apparent after Oak Park’s last reassessment in 2023. When the bills from the 2023 reassessment came out, about one-third of Oak Park homeowners experienced tax reductions. But about 40% of homeowners had double-digit tax increases.
Next week, in Part II of my article on reassessment, I will provide further details about how you can estimate the impact of the reassessment on the tax bill you receive next year.
Ali ElSaffar
Oak Park Township Assessor