State and county guides
Cook County Assessor vs. Board of Review Appeals
Cook County homeowners get two local chances to appeal each year. The first is with the Cook County Assessor, when the Assessor reassesses or opens your township. The second is with the Cook County Board of Review, a separate office that reviews the values the Assessor certified. You can file at either one or both: the Board hears your appeal whether or not you went to the Assessor, and it isn't bound by the Assessor's decision.
The two steps side by side
| Cook County Assessor | Cook County Board of Review | |
|---|---|---|
| What it's called | An "appeal" | Formally a "complaint" (the Board also calls it an appeal) |
| When | Township by township; the last day is printed on each reassessment notice | Townships open in groups after the Assessor finishes; each group stays open at least 30 days, and the Board posts the dates |
| How to file | Online with SmartFile; owners filing for themselves who can't use it may e-mail the appeal or file in person at 118 N. Clark St., Room 320 | Online through the Board's portal, or in person at 118 N. Clark St., Room 601; you can pre-file before your township opens |
| Fee | None | None |
| Evidence deadline | The appeal and all evidence by the township closing date; late appeals or evidence aren't accepted | Evidence can follow until the Board's evidence deadline for your group, after filing closes |
| Hearing | — | Optional, by phone for owners; you can waive it without penalty |
| Can your value go up? | — | Yes, but only after the Board notifies you in writing and gives you a chance to be heard |
| If you disagree | The Assessor doesn't re-review its decisions; the next step is the Board of Review | A "Re-Review" within 3 days of the decision letter (no new arguments), then the state Property Tax Appeal Board or the Circuit Court |
What each office asks for
At the Assessor, common grounds are an assessment out of line with similar homes (uniformity), a value that is too high (overvaluation), or wrong property details. If you use comparable properties, at least 3 are required and 5 are recommended, from your assessment neighborhood. You must state the estimated fair market value you believe is correct. If the home sold within two years before January 1 of the appeal year, the sale date and price must be disclosed. A dated front photo is required, except for owners filing for their own home.
At the Board of Review, every filer submits a brief, a short written explanation, with the evidence. Common grounds are lack of uniformity with similar homes, a recent purchase, recent sales of similar homes, factual errors, or damage. Compare your home with properties in the same neighborhood and the same classification code; the Board compares uniformity as building assessment divided by building square feet. Include a color photo of the front of the property taken within the last 12 months, with the date marked on the back. A purchase within three years of the January 1 lien date must be disclosed with the sales documents.
Who can file
You can file with the Assessor for your own home on your own. The Board of Review's rules let an owner file for property held in their own name; property owned by a company, an LLC, a condo association or another entity follows different filing rules, so read the Board's official rules before filing for one.
Why both steps matter for your bill
Your values move through both offices before the second-installment tax bill can be calculated. The first installment is 55% of the previous year's total bill; the second can't be calculated until the Board of Review finishes every appeal in all 38 townships. A reduction at either step lowers the value the bill is based on, and the Board only hears the current tax year, so a missed season can't be appealed there later.
If you go further, a Property Tax Appeal Board reduction on an owner-occupied home carries forward for the rest of the general assessment period unless the home sells. Cook County reassesses every three years by region; the City of Chicago is next reassessed in 2027.
Exemptions are separate
An appeal is about value. Exemptions are applied on top of it: the Homeowner Exemption lowers the equalized assessed value of an owner-occupied home by $10,000, and the Senior Exemption by a further $8,000. If one was missing from a past bill, the fix is a Certificate of Error, not an appeal; see our record correction page and our guide to exemptions to check first.
Finding your dates
Our Cook County page lists the Assessor and Board of Review windows by township with their official sources, and each township has its own page with its past deadlines.
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Sources
Official pages and documents this article relies on. Rules and dates can change each year; check the source before you file.
- Cook County Assessor: Appeals
- Cook County Assessor: Official appeal rules
- Cook County Assessor: Residential appeals
- Cook County Board of Review: Official rules
- Cook County Board of Review: Frequently asked questions
- Cook County Board of Review: How to present your case
- Cook County Board of Review: Residential hearings
- 35 ILCS 200/16-185 (Property Tax Appeal Board decisions on homes)
About this article
Written by
Property Appeal Team
Written by our research team and checked against the official sources listed above. Facts about counties come from the same verified records as our county guides; see how we verify facts.
Reviewed by
Evan Hollister
Cook County Appeals Reviewer
Focuses on Cook County assessment appeals and reviews Illinois property-tax materials, with particular attention to Board of Review procedures and supporting property evidence.