By Hani Khatib, JD, CPA, LL.M. · Tax Attorney and CPA
You appeal the assessed value, not the tax bill, and you do it township by township inside a window of about 30 days at each venue. Anyone can file, and filing is free. What an attorney changes is the case: which argument is made, what evidence carries it, and what happens when the first venue says no.
What representation involves at each venue
Cook County Assessor
The first look, decided on paper. We file the uniformity case (your assessed value per square foot against comparable homes in your neighborhood code) or the overvaluation case (a recent purchase or appraisal), with the property-characteristic corrections that the model got wrong.
Board of Review
The venue that matters. Independent of the Assessor, three elected commissioners, most residential cases decided on the papers, commercial cases with hearings. We file here whether or not the Assessor reduced, with the comparables and, for commercial property, the income and expense analysis a CPA prepares.
PTAB and the circuit court
For the cases worth taking further, mostly commercial and multi-parcel: the state Property Tax Appeal Board, or a specific-objection case in the circuit court. Evidence rules apply; this is attorney work.
What the venues actually decided last year
County-published outcomes for all residential (Class 2) appeals decided for tax year 2025, every appellant, represented or not:
| Venue | Appeals decided | Received a reduction | Average cut (winners) |
|---|---|---|---|
| Assessor | 335,919 | 49,454 (14.7%) | 9.2% |
| Board of Review | 447,784 | 189,516 (42.3%) | 6.4% |
By region the Board reduced 55.6% of north suburban appeals (the 2025 reassessment area), 37.7% in the south and west suburbs, 26.4% in the city. Township-by-township figures are in the Board of Review guide, and the case for and against representation, venue by venue, is in When Representation Matters.
When you should have an attorney
- Commercial, industrial and multi-unit property. Valued on income; the argument is a capitalization analysis, not a list of comparable homes.
- A reassessment year. In 2026 that is the south and west suburbs, where median home assessments rose 20–27%. The whole field moved; the case is about your share of it.
- After the Assessor said no. The Board is independent and reduced three times the share of appeals last year; a Board case is built, not re-sent.
- Multiple parcels, condominium associations, or a prior year with an error that needs a Certificate of Error rather than an appeal.
The fee
25% of the first year's tax savings, charged after the reduction is on the bill. No retainer, no filing fee, nothing if there is no reduction. Terms are on the pricing page.
How it works
- Enter an address or PIN in the free property check. It shows the assessment against comparable homes and the bill history, from the county's data.
- If the assessment is out of line, sign the engagement online; no paperwork.
- We file in the township's window at the Assessor, then at the Board of Review, with the evidence for each.
- The reduction appears on the next second-installment bill; the fee is invoiced against it.
Questions
Do I need an attorney to appeal my Cook County property taxes?
No. Filing is free and any owner can file. Representation matters when the evidence is contested: commercial and multi-unit property valued on income, a reassessment year when the whole township moved, a Board of Review case after the Assessor said no, or an appeal taken to the Illinois Property Tax Appeal Board.
What does a property tax appeal attorney cost in Cook County?
Our fee is 25% of the first year's tax savings, charged only if the assessment is reduced. There is no retainer, no filing charge and no fee if there is no reduction.
Which venue matters most?
The Board of Review. For tax year 2025 the Board reduced 42.3% of the residential appeals it decided county-wide, against 14.7% at the Assessor. The two venues are independent; a case can be filed at the Board whether or not it was filed with the Assessor.
How long does an appeal take?
Each township's window is about 30 days at each venue. Assessor decisions arrive after the township closes; Board decisions follow its hearings. A reduction appears on the following year's second-installment bill, and in a reassessment year it generally holds for three years.
Windows are open now in 13 townships. See where yours stands.