County Assessments Office - Alejandro Benitez, Chief Assessment Officer

Filing A Complaint

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Complaint Forms, Instructions, and Guidelines to Help with Filing a Complaint

When can Assessment Complaints be Filed with the County? What is the Deadline?

You must file within 30 days of the date of publication of the township. The links below can give the progress of the townships in McHenry County.

Township Filing Deadlines
2026 Assessment Progress Report aka "Board of Review Status Report" (Will be available shortly prior to the publication date of the first township.)
Sign-up to receive notifications your township has published, Assessment Notice Information

Rules of the McHenry County Board of Review (BOR)

2026 Board of Review Rules
Effective date 6/1/2026.
The rules can be updated as warranted.

Filing a Complaint Online

We are expanding the use of our online Complaint Submission platform, and everyone is encouraged to use this tool. It is a simple electronic form that guides you through the process of filing a complaint. If you prefer to complete a physical complaint form, please email or call to request one at assessments@mchenrycountyil.gov or (815) 338-4290.

Depending on the type of complaint, Residential or Industrial/Commercial, you will be required to complete or provide some documentation. These files should be saved to your computer and accessible prior to starting the electronic complaint form. Below are some required documents and recommendations. Click the appropriate submission button when ready.

Residential

For Residential Complaints Based on Comparable Sales or Comparable Assessments

*Required - Complete at a minimum 3 comparables in the following documents that allows for up to 9 comparables:
- Residential Comps 1 to 4
- Residential Comps 5 to 9
Optional - Pictures
- General pictures of your property, exterior and/or interior, can help the Assessor and/or the Board of Review understand your property.
- Pictures of the Comparables can show that a property is similar
Optional - Any other information that you believe is important to your complaint. (e.g. a letter or explanation)
Optional- Maps
- Providing a map of your property and identifying the comparables used on the same map can be very helpful.
- The McHenry County - Athena - Public Property Search map allows you to input parcels numbers and identifies them very conveniently.
- Any standard map that shows the proximity of the comparables is acceptable.
Here is an example of a completed residential grid form.
If you complete both the "sales" and "assessments" sections in the grid, please only upload the document once. Be sure to select your best argument for an assessment reduction. The Township and the Board of Review will still consider all data in rendering a decision.

For Residential Complaints Based on a Recent Sale of the Subject

*Required - Closing documents, Listing sheets, or any formal documentation that shows the sale met the definition of an Arm's Length Transaction.
Optional - Pictures
- General pictures of your property, exterior and/or interior, can help the Assessor and/or the Board of Review understand your property.
- Pictures of the Comparables can show that a property is similar
Optional - Any other information that you believe is important to your complaint. (e.g. a letter, explanation, or details relevant to your case.)

For Residential Complaints Based on an Appraisal

For Residential Complaints Based on a Forthcoming Appraisal

For Residential Complaints Based on Construction Costs or a Matter of Law

Submit Your Residential Complaint

Commercial / Industrial

Please provide as much information about your Commercial property using the grid provided in this section. Failure to provide adequate detail could result in an unfavorable decision with the Board of Review.
- Required* - Commercial Grid Subject Comps 1 to 4
- Commercial Grid Comps 5 to 9 if needed
Please provide as much information about your Industrial property using the grid provided in this section. Failure to provide adequate detail could result in an unfavorable decision with the Board of Review.
- Required* - Industrial Grid Subject Comps 1 to 4
- Industrial Grid Comps 5 to 9 if needed

Submit Your Commercial-Industrial Complaint

Additional Documentation

If you are returning to submit additional information

Submit Additional Documentation

Other Forms

Authorization to Represent
- Note that every representative must submit this form with an original signature or with a secure digital signature.
- In lieu of this form, similar proof of authorization must be submitted.
- Failure to do so may result in a Dismissal.
- A complaint that is dismissed cannot be appealed to the State of Illinois Property Tax Appeal Board (PTAB).
VACANCY AFFIDAVIT
- This form is to be completed when a Commercial Property, aka an Income Producing Property, is experiencing market induced vacancies.
- The Board of Review requests three years of financial reports to show the property's history.
- Note that while the vacancy rates can affect current market value, an assessed value is used for a property tax which can be shown to be different based on three years of financial reports.

For assistance with the assessment complaint, please contact our office during normal business hours (8:00 am to 4:30 pm central) at (815) 334-4290 or by e-mail at assessments@mchenrycountyil.gov

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