Du Page Tax Appeals
Property owners have an annual opportunity to appeal their assessments to the DuPage County Board of Review. The period during which an appeal may be filed ends thirty days after the publication of the township assessment roll. You may view the assessment publication dates and corresponding Board of Review Deadlines for each township on this webpage.
An assessment appeal does not address the amount of the property tax bill, it is an attempt to prove that the assessed value overstates the property’s market value, or is higher than the estimated value of similar properties.
Property owners who question their assessments are encouraged to first call or visit the Township Assessor’s office to review the information in their property files.
If the property owner still believes that his/her property is over assessed, he/she may file an assessment appeal. You may download assessment appeal forms from our forms and documents webpage. Appeal forms along with supporting evidence must be submitted in duplicate.
A property owner must provide evidence to support his/her assessment appeal. This evidence should include three (or more) comparable properties. These comparables should be similar properties to the subject, preferably within the same neighborhood.
If the appeal is based on market value, the comparables must be properties that sold recently. If the appeal is based on assessment uniformity, the comparables should be similar properties with similar amenities. The Township Assessor’s staff will also compile sales and/or uniformity comparables to present to the Board of Review.
Written decisions of the Board of Review will be mailed upon the completion of all hearings of the county. This typically occurs the following March. No decisions will be released prior to that time.
If a property owner is not satisfied by a decision of the Board of Review, he/she may then appeal to the Illinois Property Tax Appeal Board, or to the Appellate/Circuit Court.
When preparing an assessment appeal, please remember:
- The best evidence to value is a recent appraisal, a recent sale of the property, or recent sales of similar properties.
- Assessed values are required by law to be based upon the three prior years of actual sales transactions within the jurisdiction.
- For example, the 2023 assessed value was based upon sales occurring during the 2020, 2021 and 2022 calendar years.
- Be sure to review your property characteristics at the assessor’s office before filing an appeal.
- Understand that Fair Market Value is not the highest or lowest selling price of a property but the most probable selling price.
- When comparing properties in your area, use only similar properties (i.e. same design, same size, etc.).
Property taxes are determined by two separate annual cycles, the assessment cycle and the levy cycle. The Supervisor of Assessments and the Board of Review perform certain mandated functions within the assessment cycle. The following is a brief outline of some of these mandated functions presented in the context of how they interrelate with other assessment entities.
Supervisor of Assessments — Prior to January 1st of the Assessment Year
The Supervisor of Assessments meets with the Township Assessors to provide assessment administration guidelines before January 1st of the assessment year along with facilitating the Township Assessors access to the assessment administration computer system for the entry of their valuation information. (35 ILCS 200/9-15)
Township Assessor — Beginning January 1st, Completed by November 15th of Assessment Year
(General Assessment Year Procedures including 2019, 2023 . . . ) The Township Assessors record in the assessment administration computer system an assessed value for each property noting the applicability of General homestead Exemptions, Homestead Improvement Exemptions and the eligibility of preferential farm valuations where applicable.
(Non-General Assessment Year Procedures) The Township Assessors record in the assessment administration computer system an assessed value for each property that has experienced a physical change or at their discretion, requires and individual revaluation, noting the applicability of General homestead Exemptions, Homestead Improvement Exemptions and the eligibility of preferential farm valuations where applicable.
For both General and Non-General Assessment Years, the Township Assessor is required to complete the entry of their revaluation information into the assessment administration system by November 15 of the assessment year. (35 ILCS 200/9-230)
Supervisor of Assessments — Date Dependent on Completion of Prior Step
The Supervisor of Assessments grants applicable preferential assessments. The Supervisor of Assessments measurers the amount of reassessment changes caused by normal re-evaluation, the adding or removing property from the assessment rolls, and the reclassification of property. This information is used to prepare an estimate of the overall relationship between the assessed values and actual market values demonstrated by statistical analysis of a three year history of sales for each township. This ratio is known as the level of assessment. If it is determined that the assessments are not at the statutory level of assessment, an equalization factor is applied to all property within the township to globally increase/decrease the assessed values to the statutory level of assessment. The Supervisor of Assessments mails change of assessment notices and prepares assessment publication data for all properties that experience an individual valuation change. If as assessment was only adjusted by a Supervisor of Assessment’s Equalization Factor, individual notices and publication data is not required. The Supervisor of Assessments receives assessment appeal petitions and schedules assessment appeals to be heard by the Board of Review. (35 ILCS 200/9-210)
Illinois Department of Revenue — Date Dependent on Completion of Prior Step
The Illinois Department of Revenue reviews aggregate assessment data combined with historical sales data and prepares a tentative State Equalization Factor. If the Department determines that the County’s overall level of assessment is not at the statutory level of assessment, this factor will be something other than a 1.0000. Public notice and a public hearing on this tentative factor are administered by the Department. (35 ILCS 200/Art. 17)
Township Assessor — Date Dependent on Completion of Prior Step
Copies of assessment appeals are forwarded to the appropriate Township Assessor. The township reviews the evidence submitted by the taxpayer and prepares a response to the complaint that will be presented during a Board of Review hearing.
Board of Review — Date Dependent on Completion of Prior Step
The Board of Review conducts the individual hearings and renders a decision in each case. The Board of Review also acts upon all assessment revision petitions including omitted assessments, granting of certain preferential assessment classifications as provided by State Law along with compiling initial applications for non-homestead tax exemptions for final determination by the Illinois Department of Revenue. After completing the required revisions, the Board of Review certifies the assessment roll to the County Clerk. Aggregate assessment data is provided to the Illinois Department of Revenue for their review. (35 ILCS 200/Art. 16)
Illinois Department of Revenue — Date Dependent on Completion of Prior Step
The Department reviews the aggregate assessment data and independently compiled property sales information from the three years prior to the assessment year to measure the level of assessment. If the State determines that the county overall level of assessment is not at the mandated level, an equalization factor is issued to globally increase or decrease all assessed values within the county to the statutory level of assessment. (35 ILCS 200/Art. 17)
