Illinois Property Tax Appeals: How Cook, Lake & DuPage County Property Owners Can Fight Back — and Win
Illinois property tax assessments are appealable at multiple levels. Attorney Glenn L. Udell of BUPD, Ltd. guides Cook, Lake, and DuPage County property owners through assessor appeals, Board of Review, PTAB, and Circuit Court tax objection litigation.
By Glenn L. Udell ·
# Illinois Property Tax Appeals: How Cook, Lake & DuPage County Property Owners Can Fight Back — and Win
*Property Tax Law · Assessment Appeals · Commercial & Residential · Cook County · Lake County · DuPage County · Illinois*
**Featured Attorney:** Glenn L. Udell, BUPD, Ltd. **Practice:** BUPD, Ltd. **Location:** Illinois — Serving Cook County, Lake County & DuPage County **Focus:** Illinois Property Tax Appeals, PTAB, Tax Objection Litigation
Property taxes in Illinois are among the highest in the nation — and among the most frequently miscalculated. For homeowners, commercial property owners, investors, landlords, and business operators in Cook County, Lake County, and DuPage County, an inflated tax assessment is not an abstraction. It is a line item that compounds annually, quietly eroding the financial performance of every property it touches.
What most property owners do not realize is that those assessments are not final. They are appealable — at multiple levels, through multiple forums — and with the right legal counsel, they are frequently reduced. Sometimes significantly.
Attorney **Glenn L. Udell** of **BUPD, Ltd.** has built his practice on exactly this work: representing Illinois property owners through the full scope of the assessment appeal process, from initial filings before the county assessor through PTAB proceedings and Circuit Court tax objection litigation.
The Misconception That Costs Property Owners Money
The single most common misunderstanding in Illinois property tax law is the belief that the assessor determines what a property owner pays. That belief, though understandable, is incorrect — and it leads many property owners to accept assessments they should be challenging.
Here is how the system actually works.
Illinois taxing bodies — school districts, municipalities, counties, park districts, libraries, fire protection districts, and special taxing districts — establish their budgets first. Each adopts a property tax levy: the total dollar amount it intends to collect. That levy is fixed before a single assessment is calculated.
The assessor's role is not to set the tax burden. It is to allocate it. Every property owner's assessed value determines their proportionate share of the total levy. An inflated assessment does not generate more revenue for the taxing body. It transfers a disproportionate share of the collective burden onto the property owner who fails to challenge it.
This is why appeals matter. And this is why they work.
Why Assessments Become Inflated
Assessments exceed actual market value for a range of reasons — many of which are entirely correctable with the right evidence and the right advocate.
Common causes of overvaluation include assessments that do not reflect current market conditions, income assumptions on commercial properties that are unrealistic or outdated, ignored vacancy rates or deferred maintenance, failure to account for comparable properties receiving lower assessments, inaccurate rent roll analysis, and equalization factors that distort valuations across entire assessment classes.
Each of these conditions represents a legal and financial argument for reduction. The question is whether that argument is made — and made properly.
The Illinois Property Tax Appeal Process: Four Levels of Relief
Illinois law provides property owners with multiple opportunities to challenge an assessment. Understanding each level — and its specific requirements — is essential to preserving appeal rights and maximizing potential savings.
### Level 1: Appeal to the Assessor
The first opportunity to challenge an assessment arises when the township or county assessor publishes assessed values. Deadlines at this stage are extremely short and strictly enforced. Missing the filing window eliminates the right to seek relief for that entire tax year.
Effective appeals at this level require concrete evidence of overvaluation or assessment inequity: comparable sales data, photographs, engineering reports, income and expense statements, rent rolls, and where appropriate, a professional real estate appraisal.
### Level 2: Appeal to the County Board of Review
If the assessor denies relief or grants a reduction that does not adequately reflect the property's actual market value, the next step is the County Board of Review — an independent quasi-judicial body that reviews assessment disputes and can order corrections.
Each county operates on its own schedule and procedural rules. Cook County, Lake County, and DuPage County each have distinct filing requirements, evidence standards, and hearing procedures. Local knowledge and procedural experience matter significantly at this stage.
### Level 3: The Illinois Property Tax Appeal Board (PTAB)
The Illinois Property Tax Appeal Board is a state agency based in Springfield that hears appeals after county administrative remedies have been exhausted. PTAB proceedings are substantially more formal than county-level appeals. They involve written briefs, formal evidence exchanges, appraiser testimony, expert witnesses, and legal argument.
For high-value commercial, industrial, and multi-family properties, PTAB is frequently where the most significant reductions are achieved — and where having experienced property tax counsel becomes decisive.
### Level 4: Circuit Court Tax Objection Litigation
In certain circumstances, property owners may file a tax objection complaint in the Circuit Court. These cases are among the most technically demanding in real property law, requiring strict procedural compliance, sophisticated valuation evidence, and litigation strategy calibrated to both the property type and the jurisdiction.
Residential vs. Commercial Appeals: Different Evidence, Different Strategies
The approach to a property tax appeal depends substantially on the property type.
**Residential appeals** center on comparable sales analysis, assessment uniformity across similar properties, documented property condition, and neighborhood market trends. The goal is to demonstrate that the assessed value does not reflect what the property would actually sell for — or that similar properties in the same area are being assessed at lower rates.
**Commercial, industrial, and multi-family appeals** require a deeper financial analysis. Income capitalization methodology — the approach assessors use to value income-producing properties — demands scrutiny of actual rent rolls, current occupancy rates, lease terms, market vacancy studies, expense ratios, and capitalization rate analysis. Appraisals for commercial appeals typically incorporate the income approach, the sales comparison approach, and in some cases the cost approach, each weighted according to the property type and market conditions.
The complexity of commercial appeals is precisely why experienced legal representation — not just a tax consultant or property manager — produces better outcomes.
What a Professional Appraisal Adds to an Appeal
For both residential and commercial properties, a professional real estate appraisal prepared specifically for appeal purposes is often the single most persuasive piece of evidence in the record.
A well-prepared appraisal does more than assign a number. It documents the methodology, supports it with market data, applies recognized valuation standards, and creates a record that can withstand scrutiny at every level of the appeal process — including PTAB and Circuit Court.
At BUPD, Ltd., Glenn L. Udell works with qualified appraisers and financial analysts to build the evidentiary record that assessment appeals require.
Why Timing Is the First Rule of Illinois Property Tax Law
No aspect of the Illinois property tax appeal process is more consequential — or more frequently misunderstood — than timing. Deadlines are strict, short, and without exception. There is no mechanism for late filing due to oversight, confusion, or competing priorities.
Missing an appeal deadline does not mean a reduced assessment next year. It means no appeal is possible for that tax year. For a commercial property carrying a six-figure annual tax obligation, a missed deadline is a six-figure loss.
Property owners who work with BUPD, Ltd. receive proactive deadline management across all three counties — Cook, Lake, and DuPage — so that no appeal window is inadvertently closed.
BUPD, Ltd.: Illinois Property Tax Appeal Attorneys
Glenn L. Udell and BUPD, Ltd. represent property owners across the full spectrum of Illinois property tax proceedings:
- Cook County property tax appeals - Lake County property tax appeals - DuPage County property tax appeals - Illinois Property Tax Appeal Board (PTAB) proceedings - Circuit Court tax objection litigation - Commercial, industrial, multi-family, and mixed-use assessment disputes - Residential assessment appeals
BUPD, Ltd. brings legal knowledge of valuation methodology, assessor practices, procedural rules, financial analysis, and litigation strategy — the full range of disciplines that successful property tax representation requires.
The Bottom Line for Illinois Property Owners
Illinois property taxation is one of the most consequential and least understood legal systems affecting property owners in the state. An inflated assessment is not a fixed cost. It is a correctable error — one that, left unchallenged, will recur year after year.
Whether pursuing relief before the Assessor, the Board of Review, PTAB, or the Circuit Court, the property owners who recover the most are those who engage experienced legal counsel early, build a complete evidentiary record, and understand that the appeal process rewards preparation and precision.
That is the standard BUPD, Ltd. brings to every case.