Chicago's Property Tax Bills Just Hit a 30-Year High. What Every Buyer Needs to Know.
If you're buying in Chicago, the property tax number in the listing is not your property tax number. That distinction has always been true in Cook County. In 2025 and 2026, it matters more than it ever has.
Here is what happened. The Cook County Assessor's Office completed a citywide reassessment of Chicago's residential properties in 2024. The results, which hit tax bills in 2025, were significant: the median residential property tax bill in Chicago jumped 16.7% — the largest single-year increase in Illinois history. For some neighborhoods, the numbers were far more severe. In West Garfield Park, the median homeowner's bill more than doubled, rising from $1,482 to $3,448. In nine predominantly Black Chicago community areas, median residential bills jumped by more than 50%.
The mechanism behind the increases is worth understanding. Commercial property values in Chicago — particularly downtown office buildings — have declined sharply as vacancy rates have risen in the post-pandemic environment. As commercial assessments went down, the tax burden shifted. Property taxes are zero-sum within a taxing jurisdiction: when commercial values fall, residential properties absorb a larger share of the levy. The Cook County Treasurer put it plainly: "When you have a vacancy rate in commercial properties the way we do in the city right now, commercial valuations are going to go down. So, who has to pick it up? It's like a scale. If one side goes down, the other goes up."
The Board of Review, which hears property tax appeals, also cut commercial assessments by nearly 20% after the Assessor's initial valuation — while cutting residential assessments by only 1%. That shift alone transferred approximately half a billion dollars of tax burden from commercial properties to homeowners, adding roughly $700 to the average homeowner's bill in Chicago.
What this means for buyers right now
The 2026 reassessment cycle is targeting the southern and western suburbs of Cook County — the first time since the infamous 2023 reassessment that this region will be revalued. That earlier cycle produced some of the largest assessment increases in Cook County history. Homeowners and buyers in those areas should be preparing accordingly.
For buyers purchasing in Chicago proper, the immediate question is: what will your actual tax bill be at your purchase price, under current assessment levels, with the rates that now apply? The historical figure in a listing reflects what the seller paid under potentially different assessed values and different rate conditions. Your bill will be calculated on what you pay, at current rates. The gap between those two numbers can be significant.
The Illinois Department of Revenue is conducting a comprehensive study of the state's property tax system with a report due July 2026. Legislative reform is being discussed seriously for the first time in years. But "being discussed" is not the same as enacted, and buyers purchasing in 2026 should not factor potential reform into their planning.
A knowledgeable local agent will model your expected tax liability on any property before you make an offer. This is not an optional step in Chicago.
John Voirol | John's Agents | Find My Agent
SOURCES
- Illinois Answers: Record Property Tax Increases Slam Chicago Homeowners
- O'Connor: 2025 Cook County Property Tax Chaos Recap
- O'Connor: 2026 Cook County Reassessment Targets Western and Southern Suburbs
- WTTW: Cook County Assessor Pushes to Ease Property Tax Burden on Homeowners
- Cook County Treasurer's Office: Property Tax Research
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