The appeal gap: who contests their assessment, and who wins
Every property owner can appeal the Assessor’s valuation — but appeal rates and success rates vary sharply across the city. In your community area, what share of parcels appealed, and what share won a reduction? Search your address or click any community area, and switch between appeal rate, success rate, and the median reduction.
How to read this map
Appeal rate is the share of a community area’s parcels that filed an appeal in the tax year. The ramp is neutral on purpose: a high rate can mean an engaged neighborhood or an active tax-appeal industry, so the map reports it rather than judging it. Success rate is the share of appealed parcels that won a reduction — defined as the certified value coming in below the Assessor’s mailed value. Median reduction is the middle dollar reduction among winners.
The drawer shows who filed — the split between appeals filed by an agent or attorney and those filed pro se (by the owner directly). That gap is a real equity signal: representation is not evenly distributed. We report only aggregate counts; no individual agent or attorney is named. Areas with fewer than 25 appealed parcels in a year are suppressed on the success and reduction views so a thin denominator can’t read as a misleading 0% or 100%.
Source: Cook County Assessor — Appeals (open data), by tax year. This map covers tax years 2021–2025 and defaults to 2024, the most recent complete year; the county’s appeals data has a gap between tax years 2005 and 2019 that no product can fill. The Board of Review’s second-stage decisions are a planned addition. See methodology for the success definition and the year coverage.