Wrong Details on Your Property Record Card: How to Fix Them

Start with the property characteristics

Begin by checking the basic property details, and look closely at each of the following:

• Address and parcel number
• Property class
• Land size and building size
• Year built and exterior type
• Room count and bathroom count
• Basement, garage, porch, deck, and pool
• Any listed improvements

Cook County explains that a complete list of property characteristics can appear on the assessment notice or in the property listing on the assessor website. Cook County also allows a residential property owner to correct property characteristics year-round through a separate filing, which is not the same as an appeal filing.

This matters because some property owners file an appeal based only on the tax bill. The stronger starting point is the assessor's own data: if that data is wrong, you can tie your appeal to a specific record issue.

Look for details that can raise the value

Some errors matter more than others. A wrong mailing address may be a nuisance, but a wrong building size, a finished basement, an extra bathroom, a garage, a pool, or an incorrect property class can affect the value calculation far more directly.

Write down each issue as its own line in a short list. For example, you might note, "Record card says finished basement, but the basement is unfinished." Another entry might read, "Record card lists 2,400 square feet, but the county permit record and appraisal show 1,950 square feet."

Do not argue every small detail. Focus on the details that affect the value or that show the property was compared to the wrong type of home.

Collect proof before filing

Use documents that connect directly to the record issue. These can include:

• Dated photos
• A deed or a prior appraisal
• A survey or floor plan
• A permit record or contractor estimate
• An inspection report or repair invoice
• Screenshots of the assessor property record

The Illinois Department of Revenue lists property record cards, photographs, deeds, contracts, appraisals, and comparable sales as examples of evidence that may support an assessment appeal.

Keep the proof organized by issue, so that a photo of damage sits with the damage note and a square footage document sits with the square footage note. Grouping the evidence this way makes the file easier to review later.

Check whether the correction is separate from the appeal

Offices handle this differently. Some allow property data corrections outside the appeal process, some require the correction to be included with the appeal, and some allow an informal review before a formal appeal.

Miami-Dade, for example, tells property owners to contact the Property Appraiser during the review period and submit supporting documents such as dated damage photos, repair estimates, invoices, insurance documents, and comparable sales. If the concern remains unresolved, the owner can then move to a formal Value Adjustment Board appeal.

Confirm the local rule before you assume that a single filing fixes both the record and the assessed value, because a property record correction may not automatically lower the assessment for the current year.

First steps

Before you file, work through this process in order:

1. Find the current assessment notice.
2. Download or screenshot the property record card.
3. Compare each listed characteristic to the actual property.
4. Mark details that are wrong or outdated.
5. Attach proof for each issue.
6. Confirm the local appeal deadline and filing method.
7. Decide whether a property correction, a formal appeal, or both are available.

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