A higher property tax assessment does not always mean the county got the value right. In this conversation, property tax attorney Dylan Nichols explains how appeals work, what evidence can strengthen a case, when factual errors may support refunds, and why owners should review assessments before deadlines disappear.
A property tax appeal challenges the assessed value used to calculate a property owner’s share of the tax burden. The goal is not to argue that taxes should disappear. The goal is to show that the property has been valued too high compared with its actual condition, market position, or surrounding comparable properties.
A successful appeal begins with evidence that explains why this property should carry a lower assessed value than the county assigned.
Dylan Nichols and Relias Law Group handle residential, commercial, and portfolio appeals. Although the process follows a similar structure across property types, the strongest evidence changes depending on the asset, its condition, its income, and the issues that affect its marketability.
Do not wait until the tax bill creates a financial emergency. Compare the assessed value with the property’s condition, market evidence, and surrounding properties while the appeal window is still open.
In Cook County, the process may begin with an administrative appeal to the assessor. If the result is not satisfactory, the property owner may pursue review through the Board of Review and later choose between the Property Tax Appeal Board or circuit court, depending on the facts and strategy.
Property owners receive assessment notices that identify the value assigned to the property and the filing window for a challenge. Missing that window can eliminate the ordinary appeal opportunity for that tax year, which is why owners should review notices as soon as they arrive.
The evidence can be excellent and still become useless if the appeal is not filed within the required window.
The time required depends on where the case is resolved. Early administrative review may move relatively quickly, while later proceedings can take much longer. Owners should continue following payment requirements while the appeal is pending so they do not create penalties or additional problems.
Comparable properties are important, but they do not always reveal the full picture. A house may have a failing foundation system, recurring yard flooding, severe nearby nuisance conditions, deferred maintenance, unusual access problems, or another feature that makes it less desirable than similar homes nearby.
The county sees property data. The owner often knows the condition, history, and market problem that explains why the value should be lower.
Photographs, appraisals, repair records, engineering information, vacancy evidence, and other property specific documentation can help an attorney build a stronger narrative. The appeal becomes more persuasive when the evidence connects the problem directly to market value.
Foundation problems, flooding, vacancy, deferred maintenance, incorrect square footage, and other conditions may matter. Keep photographs, reports, invoices, and records that help explain the property’s real market position.
A normal appeal must generally be filed for the specific tax year. A certificate of error is different because it addresses factual mistakes in the county’s records, such as incorrect building size, missing exemptions, or another verifiable issue that caused the property to be taxed incorrectly.
Dylan explains that certain factual errors may allow an owner to seek corrections for prior years. The available period and documentation depend on the type of mistake and the applicable county process.
You usually cannot recover old taxes simply because no appeal was filed. There must be a qualifying factual error or exemption problem.
A homeowner may rely heavily on comparable sales and property condition. A commercial owner may need a strong appraisal, vacancy evidence, income information, operating details, or proof that the property has been categorized or valued incorrectly.
The episode includes a data center example where the assessor viewed the property through the lens of a valuable technology use. The successful argument focused instead on the real estate itself, an older office building, while separating the taxable land and structure from equipment that was not part of the real property valuation.
Dylan explains that the owner’s tax burden depends on more than assessed value. Taxing districts establish budgets, the overall tax base is measured, and rates are applied to collect the required levy. An appeal changes how much of that burden is allocated to one property, but it does not automatically reduce government spending.
A tax appeal can correct your share of the burden. It does not by itself change the total amount the taxing districts plan to collect.
This becomes especially important when commercial values fall. If offices, retail buildings, or other large properties receive justified reductions, more of the burden may shift toward homeowners unless the overall levy also changes.
The practical lesson is to review assessments consistently, preserve filing rights, document property problems, and seek professional help when the value appears unsupported. Even when the assessment is fair, an informed review can give the owner confidence that the bill is based on a defensible value.
Residential, multifamily, commercial, and special use properties require different evidence. Work with professionals who understand the asset, the local process, and the level of appeal needed to present the strongest case.
It challenges the assessed value assigned to the property. The owner presents evidence that the value is too high based on comparable properties, condition, market factors, income, vacancy, or another relevant issue.
Immediately after receiving it. Appeal windows can be short, and the exact deadline depends on the township, county schedule, and level of review.
Useful evidence may include comparable assessments or sales, photographs, repair estimates, appraisals, engineering information, flooding records, and documentation of conditions that reduce market value.
Sometimes, but generally only when a qualifying factual error or exemption issue supports a certificate of error or another available correction process. Missing a normal appeal deadline alone usually does not create a refund claim.
Owners should follow the current payment requirements and deadlines unless a qualified professional advises otherwise. An appeal does not automatically suspend the obligation to pay the bill.
Some firms use contingency arrangements based on a portion of the savings or recovery, while others may use different fee structures. The engagement agreement should clearly explain how the fee is calculated and when it becomes due.
Tell us what notice you received or your next court date. We’ll confirm where you are in the process and recommend your strongest next move—without panic or guesswork.
We typically respond the same business day or the next business day.
