Cook County board of review appeals open for homeowners and businesses

Cook County property owners are entering a tight appeals window as board of review deadlines open across multiple townships, including several with a Sept. 1, 2026 cutoff. The appeal process matters because missed deadlines can lock taxpayers out of any property tax protest for the year.

Why it matters: - Cook County property owners facing rising tax bills have a short window to challenge assessed values and possible errors. - Missing a Board of Review deadline can end a taxpayer’s chance to protest for the year. - Appeals can affect both homeowners and businesses, especially in townships facing reassessment or disputed values.

What happened: - Cook County board of review appeals are opening now for several townships. - The appeal process follows earlier assessor appeals that have already closed in many parts of Chicagoland. - Townships with a Board of Review deadline of Sept. 1, 2026 include Evanston, New Trier, Norwood Park, Oak Park, Riverside and Rogers Park.

The details: - Cook County has two official property tax appeal opportunities, while most Illinois counties have one. - The first step is an assessor appeal filed with the Cook County Assessor’s Office. - The second step is a Board of Review appeal, which acts as a referee between the assessor’s office and the taxpayer. - Assessor appeal deadlines generally run for 30 business days after a township reassessment notice is published. - Board of Review appeals operate on a tighter 30-day schedule. - The Board of Review hears multiple townships at once during the filing window. - A taxpayer who already filed an assessor appeal can reuse much of the same evidence for the Board of Review hearing. - If a taxpayer missed the assessor deadline, the Board of Review appeal can still serve as the next opportunity. - The Board of Review requires a valid ground for appeal, usually overassessment or lack of uniformity. - Overassessment means a property’s market value is above what it would reasonably sell for on the open market. - Lack of uniformity means a property is assessed higher than comparable nearby properties. - Overassessment cases usually require three years of sales records. - Uniformity cases require comparable assessments from nearby properties. - Comparable properties should match the taxpayer’s property as closely as possible on size, location, age, room count and other characteristics.

Between the lines: - Cook County’s appeal system is unusually active because the county has staggered township deadlines and a second official appeal step. - The volume of protests suggests many taxpayers believe their bills are inflated or inaccurate. - The process is demanding because the evidence window is short and the strongest cases depend on well-matched comparables. - A third deadline opened in December 2025, but that was described as rare, so taxpayers should treat the current filing window as their last practical chance.

What’s next: - Property owners in townships with Sept. 1, 2026 deadlines should file quickly to avoid missing the window. - Taxpayers who want to go beyond the Board of Review can later pursue the Property Tax Appeal Board, but only if they first filed a Board of Review protest. - Homeowners and businesses will likely continue pushing appeals as they try to correct assessments and lower tax bills.

The bottom line: - In Cook County, the Board of Review deadline is the key cutoff for preserving a property tax challenge, and the window is closing fast.