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Blog · Appeals · 2026-08-04 · 2 min read

Nine mistakes that sink property tax appeals

Most failed appeals fail for the same handful of reasons, and all of them are avoidable.

  1. Arguing the tax rate. The board sets assessments, not rates. This is the single most common wasted hearing.
  2. No requested value. "Too high" gives the board nothing to grant. Name a number.
  3. Comparables that are not comparable. Different class, different town, half the lot. One weak comparable taints the set.
  4. Using asking prices. A listing is not a sale.
  5. Zestimates. Not accepted as evidence of value.
  6. Comparing to the wrong year. Assessments have a valuation date; evidence has to speak to it.
  7. Missing the deadline because the notice arrived late. The clock runs from publication.
  8. Filing when you are the low one. Check the comparables in both directions before you expose yourself to a review.
  9. Making it personal. Alleging favouritism turns a records discussion into a defence. Point at the inconsistency, not at anyone.

Every one of these is avoidable in an evening's preparation, which is roughly the whole difference between appeals that work and appeals that do not.

This is general information about how Illinois assessments and appeals work. It is not legal advice, not an appraisal, and not a prediction about your case. Deadlines and rules differ by county — check yours with your Board of Review.

Check your own assessment free →

More on Appeals

The 30-day rule: the deadline most owners miss Your window opens when the township list is published, not when the notice reaches you.How to file a Board of Review appeal in Illinois The form, the evidence, the copies, and the order to do them in.What actually happens at a Board of Review hearing Ten to fifteen minutes, three people, no robes. Here is the shape of it.Yes, the board can raise your assessment It is uncommon, it is real, and it is the reason to check whether you are the low one first.

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