Assessment Inquiries

Real Estate Assessment Information Sheet – Understanding Your Assessment

Assessment values for tax year 2022, taxes payable 6/1/2023 and 9/1/2023, were published June 16, 2022 in the Kane County Chronicle. 

1-       As dictated by state statutes, your 2022 assessments were based on prior year sales from 2019, 2020 and 2021 in your defined neighborhood. Each respective property is analyzed and all improvements and property characteristics are taken into account when determining your assessment. Residential property details to consider might include: finished basements, in ground pools, decks, patios, sheds and accessory units, year built (and respective depreciation), quality of construction, lot size and interior amenities.

The St Charles Assessor re-values parcels every year based on the physical characteristics of each property as well as the overall market trends, which are based on the prior three year’s sales, as mentioned above. Comparables for each parcel can be found at the website listed directly below, or by using other real estate data sources such as local MLS services or web based real estate sites.

Neighborhood sales are found at the Kane County Supervisor of Assessments website:

KaneGIS – BOR Sales (TaxMap) (

2-       Comparable Data: If the property owner feels that the value is not properly reflected in the current assessment, there must be evidence to the contrary provided by the homeowner. The sales tool at the Kane County Assessor’s website (link above) is a great resource for localized sales geographically displayed in relation to the subject.

Additional information sources to support market value can include a recent appraisal for the purposes of a mortgage refinance or an arms-length transaction real estate purchase (refinance appraisals are not the sole piece of evidence used by the assessor to determine value due to the different criteria used for appraisals vs. the statutes outlined for assessments by the state). An arms-length sale is defined as an advertised sale between a willing and able buyer and seller. Some sales not considered arms-length for assessment purposes would include: Special Warranty Deeds, foreclosure, sheriff sales, unadvertised sales, sales between related parties and adjacent property owner sales.

Choosing real estate comparables: Property owners must consider similar properties when choosing properties to reflect their own properties value, should they not agree with their assessed value. This is the most difficult part of the assessment process and the most frequently mistaken by homeowners. Properties that are comparable to your own should be similar in style, condition, square footage and location with reasonably similar site size and amenities. Additionally, just because a property is located next to the subject property does not make it a comparable since most neighborhoods have a variety of style, quality and varying physical characteristics.

As an example, if your home is a ten year old two-story home with five bedrooms, three bathrooms and a full finished basement with additional living space and bathrooms – a comparable property would also be similar in style i.e. two-story, full basement, with similar room count, location, site size and similar overall consumer appeal and quality. Properties with adverse condition due to being a bank owned sale, significantly less square footage, far less bedrooms or bathrooms, different style or distant location could support a different assessed value and would not substantiate an assessment revision.

Before You Appeal – Homeowners should have evidence of recent neighborhood sales, similar to their own property prior to presenting an informal appeal at the assessor’s office. If the homeowner questions their property assessment based on equity, similar properties need to be presented to support an appeal. An appraisal can also be used for formal evidence. Typically three to five arms-length sales are suitable to aid the assessor in making a determination.

Property Assessment and Equalization Information –

How to File a Formal Appeal –