Triennial Reassessment
New Trier is one of the townships coming fresh off the 2025 reassessment. Every year, a third of Cook County residents are reassessed by the Cook County Assessor’s Office (CCAO), typically resulting in significant increases. New Trier was certainly hit hard, with the property value of homes increasing 39% in one year. Considering the initial value of these homes, $7.6 billion in value was added in just one year. Businesses, likewise, saw a significant 34% increase. This was compounded by the fact that the entirety of Cook County’s residential properties saw an average increase of 16% in property taxes to close 2025. While this means that the township will not undergo reassessment until 2028, taxes can still increase outside of reassessment due to jumps in tax rates and the equalization factor.
Methods Used to Lower Property Values and Taxes
Thanks to historic increases, homeowners and businesses are exploring how best to get a cut on their taxes. While Cook County has raised taxes for 30 straight years, there are still some options that taxpayers can use to help even the odds. With so much money in the balance, these techniques pay even higher dividends in New Trier than they do in the rest of Illinois. Many of these options have practically become mandatory when it comes to protecting homes and businesses from aggressive assessment.
Exemptions:
The gold standard when it comes to reducing taxable value. This is applied after the equalization factor, but before tax rates. The standard homeowner’s exemption in Cook County cuts $10,000 in equalized assessed value (EAV). There are plenty of other options, including those for people over 65, those with disabilities, and veterans. Every last exemption that a taxpayer is eligible for should be applied.
Property Tax Appeals:
These challenges to the CCAO generally go after the market value. These are used to fix issues with factual errors, lack of uniformity, or overassessment. These have become commonplace over the past decade, and even the CCAO recommends that every taxpayer appeal if possible.
Cost Segregation:
This IRS-backed technique is targeted at federal income taxes instead of property taxes, but represents one of the best property tax reduction options available to businesses. This utilizes the accelerated depreciation of real property to shield a business from income taxes, often eliminating them entirely. Often, a cost segregation study pays for itself more than a dozen times.
Cook County Appeals can Significantly Cut Taxes
While much of Cook County is catching on to the power of appeals, the homeowners and businesses of New Trier have been practicing them in volume for decades. Thanks to being loaded with premium properties, the township has always felt the gaze of the CCAO upon it and has seen some of the highest tax levies in America. By disputing the values of the CCAO every year, the people of New Trier ensure that they are only paying what they owe, and not a penny more.
An appeal starts by reviewing the assessment notice. It should be scanned for any factual errors first, as these are the easiest to remedy. Once factors like ownership, size, classification, and improvements are verified, it is time to check the values. If the market value looks incorrect or has recently spiked, then it should be protested for possible overassessment. By looking at the assessments of your neighbors, you can also see if your assessment is consistent with those that share your property’s characteristics. If your real estate is assessed higher, then you have grounds to appeal on the lack of uniformity. When choosing to appeal, you need solid grounds; you cannot protest simply because your taxes are too high.
While being late on taxes can cost taxpayers more in penalties and interest, there are other deadlines that should be tracked as well. For instance, missing the appeal or exemption deadlines means missing out on those particular avenues of tax reduction for a whole year. Cook County taxpayers do have two chances to file appeals, which is better than the rest of Illinois. First, there is the assessor appeal, which is directly with the CCAO. Then, months later, there is a formal appeal with the Board of Review (BOR).
April 1, 2026: First installment of property tax payments is due
May 7, 2026: Assessment notices mailed
May 15, 2026: Exemption filing deadline
June 22, 2026 (or 30 business days after the assessment was sent): Assessor appeal deadline
September 1, 2026: BOR appeal deadline
Pending: Second installment of taxes due
O’Connor Helps with Vital Evidence
In order for a property tax appeal to be successful in achieving a tax reduction, it needs to be backed by evidence. To show overassessment, you will need property sales dating back three years for homes or businesses that are similar to yours. To demonstrate to the CCAO or the BOR that you are being assessed unequally, you will need to collect the assessments of neighboring properties. Collecting this information and bundling it into a strong portfolio takes time, skill, and expertise.
We at O’Connor are here to help. For over 50 years, we have been gathering evidence, performing analysis, and advising clients on appeals. When you sign up with us, we will analyze your assessment for issues, dissect your values, and determine if you should appeal. Then, we will use data-driven techniques to gather the evidence needed, including using our patented databases to find the perfect comparisons in sales and assessments. Once gathered, we will coordinate an appeal with an expert attorney who knows how to impress the CCAO and BOR. You will pay nothing for this evidence unless you and your attorney can lower property taxes.
