Cook County Property Tax Appeal Guide
If your Cook County, IL property is over-assessed, you can appeal to lower your tax bill. Here are the deadlines, filing steps, and how often appeals succeed.
- Appeal deadline
- Within 30 days of township reassessment
- Appeal success rate
- 55%
- Effective tax rate
- 2.19%
- How to file
- Board of Review online appeal
- Pre-fillable appeal form
- Available via TaxCheck
How to appeal your assessment in Cook County
Compare your assessed value to recent comparable sales. If your home is assessed above market value, gather 3–6 comparable sales and file your appeal with Cook County before the deadline. A well-documented appeal with strong comps has the best chance of a reduction.
Check if you are over-assessed
Upload your assessment notice for an instant comparable-sales analysis, an over-assessment estimate, and a pre-filled appeal.
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For informational purposes only. Not legal, tax, or medical advice.