The struggle against the nation’s highest property taxes is an issue for all of Illinois, not just Chicago and Cook County. Each county has its own story and its own tax rates, equalization factors, and issues that influence taxes and property valuations. At the same time, many counties are seeing the burden of out-of-control pension programs weighing them down more every year. While Cook County is the focus, the rest of Illinois should not be ignored, especially as appeal season begins in earnest.
The collar counties around Chicago have the largest budgets, tax bases, and concerns outside of Cook County itself. These vital communities are both part of Chicagoland and economic powerhouses in their own right. Like the rest of the state, many townships in the collar counties are opening up for appeal, giving homeowners and businesses one shot to challenge the values put forward by their assessors. In this article, we will go over some of the deadlines and why taxpayers should appeal when given the opportunity.
The Collar Counties
The “collar counties” refer to the areas that surround Cook County and Chicago. The two have been linked for decades, boasting a symbiotic metropolitan relationship that is one of the largest metro areas in the nation. These counties are DuPage, Grundy, Kane, Kendall, Lake, McHenry, and Will. Despite their reputation as suburbs, each has many large and thriving communities and cities, including Aurora, Joliet, Kaneville, and more. Some of the wealthiest and most iconic townships, cities, and communities in the Chicagoland area are in the collar counties. This close connection to Cook County means that the outlying areas are strongly influenced by what happens in the city.
Rising Costs
Illinois has the highest property taxes in the nation, recently unseating New Jersey for that dubious distinction. While the main driver for this is Cook County, the rising costs are certainly not limited there. As more residents either flee Cook County for affordability or better amenities, such as schools, the demand for property in the collar counties continues to grow, raising property values and the taxes tied to homes and businesses. These issues are not strictly linked to Chicago, however, and many intrinsic issues related to Illinois loom large in these suburban communities.
The largest of these is a long-term pension issue that dates back almost a century. Thanks to pensions being a constitutionally protected right in Illinois, there is no real way to curtail these costs through legislation. The “Edgar Ramp,” a policy from the 1990s meant to kick pension issues down the road, is reaching its conclusion, which means increasing costs every year, ending in 2045. In addition, statewide tax protections such as caps are often circumvented by using options like tax incremental financing (TIFs). The amenities that make the collar counties so appealing are also a big contributor, as they need extensive funding. As Illinois itself has slowed local funding, along with federal cuts, property owners are being asked to pay more of the bill every year.
Exemptions Help Cut Costs
Since legislation and judicial solutions to many of these issues are impossible or rare, it usually falls to homeowners and businesses across Illinois to lower their taxes on their own. The first option is exemptions, which every property owner should maximize. The standard Illinois homestead exemption lowers the equalized assessed value (EAV) of a home by $8,000, which can produce significant savings. This can be combined with other specialty exemptions, such as those for veterans, seniors, and people with disabilities. Some of these exemptions have income requirements, while others do not. While exemptions are vital to any property owner’s bottom line, a growing number are embracing property tax appeals as well.
Appeals Benefit All Property Owners
While recent years have seen Cook County’s many errors bring appeals to the forefront, these are a right that every resident of Illinois has. These are challenges directly to the assessor’s valuation of properties. These assessments act as the basis for all property taxes, and getting a reduction on them can lead to large savings. Even if the savings through an appeal are minimal, they can lock in the true value of a home or business, ensuring that a taxpayer is only paying their fair share. An established value can also help future appeals, and is one of the better ways to protect against surging property values.
While they pair well with exemptions, appeals can also be used for properties that have few exemptions or none at all. They are particularly useful for businesses, rental homes, or second houses. They, of course, are also extremely useful for homestead properties, and can enhance exemptions by lowering the value of a house before the EAV is calculated and reduced by exemptions. Many assessors in Illinois recommend that property owners of all types appeal annually, as it ensures accountability and equality. Appeals do require evidence and the appropriate grounds to be successful, but are generally always worth it in Illinois.
Collar County Appeals Windows and Deadlines
Illinois has a limited timeframe for appeals to be filed. These are established by individual townships, though most counties will share similar deadlines. While Cook County has several deadlines, people in the rest of Illinois have only one chance to file. This is because their appeals must be filed with the local Board of Review (BOR). While you can contact your assessor and ask for a reduction, you cannot make a formal appeal to them like the residents of Cook County can. The collar counties are entering their appeal season, and though a few townships have closed, most are getting ready to open soon, while others are currently taking appeals. Most of the collar counties have appeal deadlines between July and September.
Current Kane County Deadlines
Big Rock: August 17, 2027
Blackberry: July 27, 2026
Geneva: August 17, 2026
Current Lake County Deadlines
Benton: August 24, 2026
Ela: August 24, 2026
Current McHenry County Deadlines
Chemung: August 13, 2026
Richmond: August 6, 2026
Current Will County Deadlines
All townships: September 14, 2026
O’Connor Helps the People of Illinois by Gathering Evidence
Appeals in Illinois are generally targeted against overassessment or unfair assessment. Overassessment is when a home or business is assessed for more than what it is worth. Under Illinois law, all properties with similar attributes in an area should be assessed equally, which is where problems with unfair assessment can be challenged. To prove these grounds, you must have the evidence to show that your home or business is incorrectly assessed. This is achieved through sales records going back three years for overassessment or gathering current assessments when it comes to lack of uniformity. No matter the county or township, the gathering of evidence is usually the largest barrier of entry for people looking to file an appeal.
O’Connor is here to even the odds. For over 50 years, we have helped clients across the nation. In Illinois, we assist you by analyzing your assessment to spot errors. After using data-driven techniques to find any issues, we will consult our proprietary databases to locate the best possible comparable properties. Once the analysis is complete and the evidence is gathered, we will coordinate an appeal with a law firm that specializes in property taxes. You will not pay for the analysis or evidence unless your taxes are lowered.
