Kendall County Property Tax Appeal — Illinois

Rob Hartley·Updated March 5, 2026

Kendall County is located in the Chicago metropolitan area with Yorkville serving as the county seat. According to the 2020 census, the county has a population of 131,869 and was the fastest-growing county in the United States between 2000 and 2010. Major population centers include Oswego (the most populous municipality), Yorkville, Montgomery, and Plano. Property tax appeals are particularly important in Kendall County due to the significantly higher tax burden compared to state and national averages—the median annual property tax bill of approximately $7,273 to $8,090 is roughly three times the national median of $2,400.

Notable cities: Yorkville, Oswego, Montgomery, Plano, Minooka

Median Home

$257,000

Tax Rate

2.83%

Annual Tax

$7,273

Population

131,869

2026 Appeal Deadline: 30 days from assessment notice publication date

Assessment notices are typically published in mid-September. Property owners have 30 days from the publication date of the assessment notice to file an appeal with the Kendall County Board of Review. For the 2025 assessment year, the appeal period for most townships ran from September 18, 2025 through October 20, 2025. For the 2026 assessment year, the deadline will be 30 days from when your township's assessment notice is published in September 2026.

Property in Kendall County, Illinois — local tax assessment and appeal guide

How Kendall County Assesses Property

33.33%of market value

Assessed by: Kendall County Supervisor of Assessments

Assessment cycle: annual

Notices typically mailed: September (typically mid-September)

In Kendall County, property is assessed at 33.33% of its fair market value as mandated by Illinois law. This means if your home's market value is $257,000 (the county median), your assessed value would be $85,667 ($257,000 × 0.3333). After applying the $6,000 general homestead exemption, your taxable assessed value would be $79,667. At Kendall County's effective tax rate of 2.83%, this would result in an annual tax bill of approximately $7,273.

The Appeal Process

Appeals are heard by the Board of Review. After filing your appeal, the Kendall County Board of Review will schedule a formal hearing where you will be sworn in as a witness. You'll present your evidence, including comparable sales, photographs, and any other documentation supporting your opinion of fair market value. The Board will review your case and issue a written decision, which may reduce, maintain, or in rare cases increase your assessment.

Step 1: Contact your township assessor for an informal review. Request a review of your assessment by calling your township assessor's office or emailing them with your concerns. This informal review may resolve the issue without needing a formal appeal.

Step 2: Gather comparable sales evidence. If the informal review doesn't resolve your concerns, collect information on at least 3 comparable properties that sold within 12 months before January 1 of the assessment year. Sales data is available from your township assessor's office.

Step 3: Complete the Board of Review complaint form. Download and complete the Residential Assessment Complaint Form and required Residential Comparison Grid from https://www.kendallcountyil.gov/offices/assessments/forms. Include your property details, proposed assessed value, and comparable property information.

Step 4: File your appeal with the Board of Review within 30 days of assessment notice publication. Submit the completed forms, comparison grid, and all supporting evidence (comparable sales, photos, appraisals, repair estimates) to the Kendall County Board of Review by mail, in-person, or following online instructions. The deadline is strictly enforced.

Step 5: Attend the Board of Review hearing. After filing, you will be scheduled for a hearing before the Kendall County Board of Review. Present your evidence and testimony under oath. The Board will review your case and issue a written decision.

Step 6: If unsatisfied with the Board of Review decision, appeal to the Illinois Property Tax Appeal Board (PTAB). You have 30 days from the Board of Review's final decision to file an appeal with PTAB at www.ptab.illinois.gov. This is the state-level administrative appeal.

Step 7: As a final option, appeal to circuit court. If PTAB denies your appeal, you may file a lawsuit in Kendall County Circuit Court challenging the assessment, though this requires legal representation and court fees.

Required form: Kendall County Board of Review Residential Assessment Complaint Form (with required Residential Comparison Grid)

Filing Methods

online:Forms and instructions available at https://www.kendallcountyil.gov/offices/assessments/forms

mail:Kendall County Supervisor of Assessments, 504 S. Main Street, Yorkville, IL 60560

in-person:504 S. Main Street, Yorkville, IL 60560 (County Office Building), Monday-Friday 8:00am-4:30pm

email:Contact township assessor or county office - forms must be completed and submitted with all required documentation

Evidence to Bring

Comparable sales (properties similar to yours that sold within 12 months before January 1 of the assessment year)Recent appraisal report (if available)Photographs showing property condition or defectsRepair estimates or evidence of needed repairsDocumentation of property characteristics (square footage, age, condition)Completed Residential Comparison Grid form

Kendall County Assessor Contact

Kendall County Supervisor of Assessments

Phone: 630-553-4146

Address: 504 S. Main Street, Yorkville, IL 60560

Website: https://www.kendallcountyil.gov/offices/assessments

Online Portal: https://www.kendallcountyil.gov/offices/assessments/forms

Hours: Monday through Friday, 8:00am - 4:30pm (except holidays)

Tax Exemptions in Kendall County

General Homestead Exemption

$6,000 reduction in EAV

Reduces the equalized assessed value (EAV) of your primary residence

Eligibility: Property must be occupied as the principal dwelling place by the owner as of January 1 of the assessment year. Owner must have legal or equitable interest and be liable for property taxes. Driver's license must reflect the property address.Deadline: Contact the Kendall County Supervisor of Assessments at 630-553-4146 to verify you are receiving this exemption or to apply

Senior Citizens Homestead Exemption

$5,000 reduction in EAV

Additional exemption for homeowners age 65 and older

Eligibility: Homeowner must be 65 years of age or older within the assessment year, own and occupy the home as principal residence, and be liable for property taxes. Must file an application.Deadline: Contact Kendall County Supervisor of Assessments at 630-553-4146 for application

Senior Citizens Assessment Freeze Homestead Exemption

Assessed value frozen at base year level

Freezes the assessed value at the year you become eligible, preventing increases

Eligibility: Homeowner must be 65 or older, meet residency requirements, and have a maximum annual gross household income of $65,000 or lessDeadline: Contact Kendall County Supervisor of Assessments at 630-553-4146

Home Improvement Exemption

Up to $75,000 in added value annually for 4 years

Exempts the added value from new improvements for four years

Eligibility: Available for new improvements to homestead property. Exemption continues for four years from the date the improvement is completed and occupied. No application needed—township assessor certifies the improvement.Deadline: Automatically applied by township assessor upon completion of improvement

Disabled Veterans Standard Homestead Exemption

$2,500 (30-49% disability), $5,000 (50-69% disability), or first $250,000 of assessed value exempt (70%+ disability)

Reduction based on service-connected disability percentage

Eligibility: Veteran with service-connected disability certified by U.S. Department of Veterans Affairs. Must own and occupy property. Annual application required unless 100% Total and Permanently disabled or WWII veteran.Deadline: Annual application required; renewal forms mailed around July 4 each year. Contact 630-553-4146

Disabled Persons Homestead Exemption

$2,000 reduction in EAV

Reduction for property owned by a disabled person

Eligibility: Property must be owned by a qualifying disabled person. Annual application required.Deadline: Annual application deadline—contact Kendall County Supervisor of Assessments at 630-553-4146

Returning Veterans Homestead Exemption

Varies based on eligibility

Exemption for veterans returning from active duty in armed conflict

Eligibility: Illinois resident who served in U.S. Armed Forces, Illinois National Guard, or U.S. Reserve Forces and is returning from active duty in an armed conflict during the assessment year. Must own or have legal interest in property as principal residence on January 1.Deadline: Contact Kendall County Supervisor of Assessments at 630-553-4146

Official Resources

Kendall County Supervisor of Assessments Website →

Official county assessor website with information on assessments, exemptions, Board of Review, and contact information for township assessors.

Kendall County Assessment Appeal Forms →

Download the Residential Assessment Complaint Form, Residential Comparison Grid, and other forms needed to file your property tax appeal.

Illinois Property Tax Appeal Board (PTAB) →

State-level appeal board where you can file an appeal if you disagree with the Kendall County Board of Review decision; includes eFiling portal, forms, and instructions.

Kendall County Property Tax Inquiry →

Search and view property assessment information, tax bills, and property characteristics for parcels in Kendall County.

Check Your Kendall County Assessment

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Frequently Asked Questions

What is the deadline to appeal my property taxes in Kendall County for 2026?

The deadline to file a property tax appeal in Kendall County is 30 days from the date your township's assessment notice is published in the newspaper. Assessment notices are typically published in mid-September each year. For the 2026 assessment year (affecting your 2027 tax bill), notices will be published in September 2026, and you will have 30 days from that publication date to file your appeal with the Kendall County Board of Review. After this 30-day window closes, the Board of Review is prohibited by law from accepting assessment complaints for properties in your township, so it is critical to act quickly once you receive your notice.

How do I file a property tax appeal in Kendall County online?

While Kendall County does not currently offer a fully online appeal filing portal, you can access all necessary forms and instructions online at https://www.kendallcountyil.gov/offices/assessments/forms. Download the Residential Assessment Complaint Form and the required Residential Comparison Grid, complete them with your property information and comparable sales data, and submit them to the Kendall County Supervisor of Assessments. You can file by mail to 504 S. Main Street, Yorkville, IL 60560, or deliver in person during office hours (Monday-Friday, 8:00am-4:30pm). Before filing a formal appeal, it's recommended to contact your township assessor for an informal review, which can often be initiated by email and may resolve your concerns without needing to file with the Board of Review.

What is the homestead exemption worth in Kendall County?

The General Homestead Exemption in Kendall County reduces your property's equalized assessed value (EAV) by $6,000, which is the amount used to calculate your tax bill. On a typical property with Kendall County's effective tax rate of approximately 2.83%, this $6,000 exemption saves homeowners around $170 per year in property taxes. If you are 65 or older, you can also qualify for an additional Senior Citizens Homestead Exemption worth $5,000 in EAV reduction (approximately $141 in annual tax savings). To receive any homestead exemption, your driver's license must reflect the property address, and you must occupy it as your principal residence. Contact the Kendall County Supervisor of Assessments at 630-553-4146 to verify you are receiving all exemptions for which you qualify.

What happens at a Board of Review hearing in Kendall County?

At a Kendall County Board of Review hearing, you will be formally sworn in as a witness by the Clerk of the Board of Review and given the opportunity to present your case under oath. You should bring all evidence supporting your opinion of your property's fair market value, including your completed Residential Comparison Grid showing at least three comparable properties that sold within 12 months before January 1 of the assessment year, photographs of your property, appraisals if available, and documentation of any defects or needed repairs. The Board will review your evidence, may ask questions, and will also consider information from the township assessor. After the hearing, the Board will issue a written decision that may reduce, maintain, or in rare cases increase your assessment. The entire process is designed to ensure fairness and uniformity in property assessments across the county.

How much can I save by appealing my property taxes in Kendall County?

The amount you can save by appealing your property taxes in Kendall County depends on how much your assessment is reduced and the tax rate in your area. For example, if your assessed value is reduced by $10,000 and Kendall County's median effective tax rate is 2.83%, you would save approximately $283 per year in property taxes. Given that the median annual tax bill in Kendall County is $7,273—significantly higher than the national median of $2,400—even a modest reduction in assessed value can result in meaningful savings. Successful appeals typically require strong evidence such as recent comparable sales showing lower values, professional appraisals, or documentation of property defects. Many property owners find that working with their township assessor for an informal review before filing a formal appeal can result in voluntary reductions without the need for a hearing.

What evidence do I need for a Kendall County property tax appeal?

To successfully appeal your property taxes in Kendall County, you need to complete the required Residential Comparison Grid form showing at least three comparable properties that are similar to yours in size, age, location, and condition. The Board of Review will only consider sales that occurred within 12 months prior to January 1 of the assessment year, so your comparables must be recent. Additional helpful evidence includes a professional appraisal report if you have one, photographs showing your property's condition or any defects, repair estimates documenting needed work, and any documentation supporting your opinion of fair market value. Information on comparable properties is available from your local township assessor's office. The Board requires that you submit an accurate and complete comparison grid—incomplete or 'homemade' grids will be returned, and you must resubmit within 10 business days or risk denial of your appeal.

Can I appeal my Kendall County property taxes every year?

Yes, Illinois law gives you the right to appeal your property assessment every year in Kendall County. Each year, when assessment notices are published (typically in mid-September), you have 30 days to file an appeal with the Board of Review if you believe your assessment is incorrect or not uniform with comparable properties. Even if you appealed in previous years, you can file again if you have new evidence or if market conditions have changed. Annual assessments are determined based on the property's value as of January 1 of each year, using sales studies from the three most recent years. However, keep in mind that once you receive your tax bill (typically mailed in May), it is too late to appeal the assessment for that year—appeals must be filed during the 30-day window after assessment notice publication in September.

What if I disagree with the Kendall County Board of Review decision on my appeal?

If you are not satisfied with the Kendall County Board of Review's decision on your property tax appeal, you have the right to file a further appeal with the Illinois Property Tax Appeal Board (PTAB) within 30 days of the Board of Review's final decision. PTAB is a state-level quasi-judicial body that provides an unbiased forum to contest property assessments. You can file your PTAB appeal online at www.ptab.illinois.gov or by mail to their Springfield office. If PTAB also denies your appeal or you disagree with their decision, you may file a lawsuit in Kendall County Circuit Court as a final option, though this typically requires hiring an attorney. Each level of appeal provides an additional opportunity to present evidence and argue for a fair assessment based on the weight of the evidence.

For state-wide appeal information including Illinois's assessment ratio and deadlines, see our Illinois Property Tax Appeal Guide →

Considering professional help with your appeal? Compare pricing, coverage, and pros/cons in our Best Property Tax Appeal Services (2026) or browse side-by-side service comparisons →

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← All Illinois property tax appeal info

Sources: https://www.kendallcountyil.gov/offices/assessments | https://www.ownwell.com/trends/illinois/kendall-county | https://en.wikipedia.org/wiki/Kendall_County,_Illinois | https://www.kendallcountyil.gov/offices/assessments/exemptions | https://kendalltwp.com/officials/assessor/ | https://www.ptab.illinois.gov/

Last verified: 2026-03-05