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Blog · Evidence · 2026-08-03 · 2 min read

Building an evidence packet a board can actually use

One page of argument, one table, and the records behind it. In that order.

Boards read quickly and hear many cases. Structure earns attention.

Page 1 — the argument

Property, PIN, current assessment, requested assessment, and the ground in one sentence: "This parcel is assessed $X. Four parcels of the same class and town, within 8% on lot and building size, are assessed a median of $Y. I request $Y." Nothing else.

Page 2 — the comparison table

One row per comparable: PIN, address, class, lot size, building size, year built, assessed value, assessed per square foot. Your own property in the same table, marked. The reader should be able to see the claim without reading a sentence.

Pages 3+ — the records

A printout from the county portal for each comparable. This is what turns your table from an assertion into something verifiable.

Then any factual evidence

Photographs, survey, plans, appraisal — only if they support the specific ground you named.

What to leave out

Your tax bill history. Automated estimates. Anything about the rate. Anything about your circumstances. None of it is within the board's power to act on, and it dilutes what is.

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 Evidence

How to find comparable properties for a tax appeal Start from the county's own records, not from what you know about the neighbourhood.What makes a comparable good enough to use Similarity on recorded attributes, proximity, and nothing clever. Four tight ones beat twenty loose.Using your county's parcel search like an assessor would Every Illinois county publishes a searchable roll. Most owners never open theirs.Assessed value per square foot: the number that makes comparisons possible Raw assessments cannot be compared. Rates can.

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