Grundy County Property Tax Appeal — Illinois

Rob Hartley·Updated March 5, 2026

Grundy County, located in northeastern Illinois approximately 60 miles southwest of Chicago, has a population of 52,533 as of the 2020 census with Morris as the county seat. The county is part of the Chicago metropolitan area and includes notable cities such as Morris, Coal City, Minooka, and Channahon. Property tax appeals are particularly important here due to the county's significantly higher-than-average tax burden—with a median effective tax rate of 2.61%, more than double the national median of 1.02%, and a median annual tax bill of $3,869 compared to the national median of $2,400. Homeowners in Grundy County face one of the highest property tax rates in Illinois, making assessment accuracy critical to avoiding overpayment.

Notable cities: Morris, Coal City, Minooka, Channahon, Seneca

Median Home

$193,300

Tax Rate

2.61%

Annual Tax

$3,869

Population

52,533 (2020 census)

2026 Appeal Deadline: Varies by township; typically late November (for 2025 tax year, many townships had November 27, 2025 deadline)

Appeal deadlines in Grundy County vary by township and are typically set in late November each year. For example, in 2025, most townships including Morris, Coal City, Braceville, and others had a deadline of November 27, 2025. The deadline is based on when the Board of Review convenes in your specific township. Property owners should contact the Supervisor of Assessments office at (815) 941-3269 to confirm the exact deadline for their property, as missing this deadline means waiting until the next assessment year to appeal.

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

How Grundy County Assesses Property

33.33%of market value

Assessed by: Grundy County Supervisor of Assessments (with initial assessments by Township Assessors)

Assessment cycle: annual

Notices typically mailed: Spring (typically mid-April)

In Grundy County, Illinois law requires property to be assessed at 33.33% of its fair market value. This means your assessed value is exactly one-third of your property's market value. For example, if your home's market value is $193,300 (the county median), your assessed value would be $64,433 ($193,300 × 33.33%). At Grundy County's effective tax rate of 2.61%, this would result in approximately $5,046 in annual property taxes. Understanding this relationship is essential when appealing your assessment—you need to prove that the market value used by the assessor is too high, which will automatically lower your assessed value and reduce your tax bill.

The Appeal Process

Appeals are heard by the Board of Review. The Grundy County Board of Review consists of three members who hear complaints from taxpayers regarding property assessments. During your hearing, you'll present evidence showing either that your property's market value is lower than the assessor's estimate or that your property is assessed unequally compared to similar properties. The Board has the authority to lower, raise, or maintain your assessed value based on the evidence presented.

Step 1: Review your assessment notice (mailed in mid-April) carefully to verify your property's market value and assessed value are accurate. Compare your assessed value to similar properties in your neighborhood using the county's online property search at grundyil.devnetwedge.com.

Step 2: Gather supporting evidence including recent comparable home sales (within the past 12-24 months), photographs of your property showing any defects or needed repairs, recent appraisals, property record cards for comparable properties, and documentation of any factors that may reduce your property's value.

Step 3: File Form PTAX-230 (Non-farm Assessment Complaint) or a written complaint with the Grundy County Board of Review before the township-specific deadline, typically in late November. Include all supporting documentation with your filing. Contact the Supervisor of Assessments at (815) 941-3269 to confirm your deadline.

Step 4: Attend the Board of Review hearing where you'll present your evidence to the three-member Board. The Supervisor of Assessments serves as clerk and is present at all hearings. Be prepared to explain why your property's assessed value should be reduced, citing specific comparable sales or property conditions.

Step 5: Receive the Board of Review's written decision, typically mailed within several weeks of your hearing. If you disagree with the decision, you have 30 days from the postmark date to appeal to the Illinois Property Tax Appeal Board (PTAB).

Step 6 (if needed): File an appeal with the Illinois Property Tax Appeal Board (PTAB) within 30 days of receiving the Board of Review's decision. PTAB appeals require specific forms and evidence submission. Contact PTAB at 401 South Spring, Room 402, Springfield, IL 62706.

Step 7 (if needed): If still unsatisfied after PTAB review, you may file a tax objection complaint in Grundy County Circuit Court. Consult with an attorney for this level of appeal, as legal representation is typically necessary for court proceedings.

Required form: Form PTAX-230 (Non-farm Assessment Complaint) or written complaint letter

Filing Methods

mail:Grundy County Supervisor of Assessments, 111 E. Washington St., Morris, IL 60450

in-person:Grundy County Courthouse, 111 E. Washington St., Morris, IL 60450, Monday-Friday 8:00 AM - 4:30 PM

phone:Call (815) 941-3269 for filing instructions and assistance

Evidence to Bring

Recent comparable home sales data (property record cards, photos, and sale prices of similar properties)Professional appraisal report (if available)Photographs showing property condition, defects, or needed repairsCopy of your property record card and assessment noticeReal estate transfer declaration or purchase contract if recently purchasedDocumentation of any factors reducing value (structural issues, flood damage, environmental concerns)

Grundy County Assessor Contact

Grundy County Supervisor of Assessments

Phone: (815) 941-3269

Address: Grundy County Courthouse, 111 E. Washington St., Morris, IL 60450

Website: https://www.grundycountyil.gov/services/assessor/

Online Portal: https://grundyil.devnetwedge.com/

Hours: Monday - Friday: 8:00 AM - 4:30 PM

Tax Exemptions in Grundy County

General Homestead Exemption

Up to $6,000 reduction in EAV

Reduces the equalized assessed value (EAV) of owner-occupied primary residences

Eligibility: Available to persons who own and occupy their home as their principal residence as of January 1 of the assessment year. Property owner must be liable for payment of property taxes. This is a one-time application that does not require annual renewal.Deadline: Can be filed anytime during the assessment year; no annual deadline

Senior Citizen Homestead Exemption

$5,000 reduction in EAV (in addition to General Homestead Exemption)

Additional exemption for seniors age 65 and older who own and occupy their primary residence

Eligibility: Available to homeowners who are 65 years of age or older by December 31 of the assessment year, own and occupy the property as their primary residence, and are liable for property taxes. One-time application with no annual renewal required.Deadline: Can be filed anytime during the year you turn 65

Senior Citizens Assessment Freeze Homestead Exemption

Freezes EAV at base year level (does not freeze tax rate, only assessed value)

Freezes the equalized assessed value at a base year amount, preventing increases due to rising property values

Eligibility: Available to seniors 65 or older who have owned and lived in their home for at least two consecutive years as of January 1, with total household income of $75,000 or less in the year prior to application. Must be liable for property taxes.Deadline: Must file initial application and renew annually; typically due by July 1

Disabled Persons' Homestead Exemption

$2,000 reduction in EAV

Annual reduction in assessed value for persons with disabilities

Eligibility: Available to disabled persons who own or have legal/equitable interest in the property, occupy it as their primary residence, and are liable for property taxes. Must provide proof of disability with initial application (Form PTAX-343).Deadline: Must file initial application and renew annually with Form PTAX-343-R

Standard Homestead Exemption for Veterans with Disabilities (SHEVD)

$2,500 reduction for 30-49% disability; $5,000 reduction for 50-69% disability; 100% exemption for 70-100% disability

Reduction in assessed value based on service-connected disability percentage

Eligibility: Available to veterans with service-connected disabilities certified by the U.S. Department of Veterans Affairs who own or lease their primary residence and are liable for property taxes. Disability percentage determines exemption amount.Deadline: Initial application with Form PTAX-342; must renew annually with Form PTAX-342-R

Disabled Veterans' Homestead Exemption (DVHE)

Up to $100,000 reduction in assessed value

Exemption for specially adapted housing for veterans with disabilities

Eligibility: Available for housing owned and used exclusively by a disabled veteran where federal funds were used for purchase or construction of specially adapted housing. Must be certified by Illinois Department of Veterans' Affairs. Also available to unmarried surviving spouse.Deadline: Must be established annually through Illinois Department of Veterans' Affairs

Homestead Improvement Exemption

Up to $75,000 in fair cash value ($25,000 in assessed value) of improvement

Exempts the increased value from new improvements or rebuilding for four years

Eligibility: Available for owner-occupied properties where improvements (such as room additions, decks, garages) have been completed. Exemption continues for four years from date of completion. May be granted automatically or may require Form PTAX-323.Deadline: File upon completion of improvement; exemption lasts four years

Official Resources

Grundy County Supervisor of Assessments - Official Website →

Access forms, exemption information, Board of Review details, and contact information for the Grundy County assessment office.

Grundy County Property Tax Inquiry System →

Search and view property assessments, tax bills, and property record cards for any parcel in Grundy County online.

Illinois Property Tax Appeal Board (PTAB) →

File state-level appeals, download forms, check appeal status, and learn about the PTAB appeal process for Grundy County property owners.

Illinois Department of Revenue - Property Tax Appeals Guide →

Official state guidance on filing property tax assessment appeals, required forms (PTAX-230), evidence requirements, and appeal procedures.

Grundy County Appeal Statistics

Success Rate

Over 95% of appeals find some sort of success (per property tax consultant data)

Check Your Grundy County Assessment

Enter your address to see if your Grundy County property is overassessed.

✓ All 50 states✓ Instant results✓ $49 flat fee

Frequently Asked Questions

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

The appeal deadline in Grundy County varies by township and is typically set in late November each year. For the 2025 tax year, most townships including Morris, Coal City, Braceville, and others had a deadline of November 27, 2025. The 2026 deadlines will likely follow a similar pattern but may vary. Since deadlines are township-specific and can change annually, it's critical to contact the Grundy County Supervisor of Assessments office at (815) 941-3269 immediately upon receiving your assessment notice (typically mailed in mid-April) to confirm your exact deadline. Missing this deadline means you cannot appeal until the next assessment year, potentially costing you thousands of dollars in overpaid taxes.

How do I file a property tax appeal in Grundy County?

To file a property tax appeal in Grundy County, you must submit Form PTAX-230 (Non-farm Assessment Complaint) or a written complaint to the Grundy County Board of Review before your township's deadline. You can file in person at the Grundy County Courthouse, 111 E. Washington St., Morris, IL 60450 (Monday-Friday, 8:00 AM-4:30 PM), by mail to the same address, or by calling (815) 941-3269 for filing instructions. Your appeal must include supporting evidence such as recent comparable sales, photographs of your property, and documentation of any factors that reduce your property's value. After filing, you'll be scheduled for a hearing before the three-member Board of Review where you'll present your case. It's important to be prepared with organized evidence and a clear argument for why your assessed value should be reduced.

What is the homestead exemption worth in Grundy County?

The General Homestead Exemption in Grundy County reduces your property's equalized assessed value (EAV) by up to $6,000, which is the standard amount for all Illinois counties except Cook County. At Grundy County's effective tax rate of 2.61%, this $6,000 EAV reduction saves homeowners approximately $157 annually in property taxes. If you're 65 or older, you can also claim the Senior Citizen Homestead Exemption for an additional $5,000 EAV reduction (saving approximately $131 more per year), for a combined savings of about $288 annually. These exemptions are one-time applications that don't require annual renewal. To apply, contact the Supervisor of Assessments at (815) 941-3269 or visit the office at 111 E. Washington St., Morris, IL 60450 during business hours.

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

The amount you can save by appealing your property taxes in Grundy County depends on how much your assessed value is reduced. With the county's 2.61% effective tax rate, every $1,000 reduction in your property's market value saves approximately $8.70 in annual taxes (because assessed value is 33.33% of market value). For example, if you successfully argue that your home's market value should be $180,000 instead of $193,300 (the county median), that's a $13,300 market value reduction, which translates to a $4,433 assessed value reduction and approximately $116 in annual tax savings. According to property tax consultant data, over 95% of appeals in Grundy County result in some level of success. Given that the median annual tax bill in Grundy County is $3,869—significantly higher than the national median of $2,400—even a modest assessment reduction can result in meaningful savings year after year.

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

For a successful Grundy County property tax appeal, you need compelling evidence that either your property's market value is lower than the assessor's estimate or that your property is assessed unequally compared to similar homes. The most effective evidence includes: (1) recent comparable home sales (within 12-24 months) from your neighborhood showing lower prices than your assessed value, with property record cards and photos; (2) a professional appraisal if you have one; (3) photographs clearly showing your property's condition, defects, needed repairs, or any factors that reduce value; (4) your property record card and assessment notice; (5) documentation of structural issues, water damage, environmental concerns, or other problems; and (6) evidence of unequal assessment by comparing your assessed value per square foot to similar neighboring properties. The Board of Review will evaluate the weight and credibility of your evidence, so organization and thoroughness are essential for a successful appeal.

Can I appeal to the Illinois Property Tax Appeal Board if the Grundy County Board of Review denies my appeal?

Yes, if you disagree with the Grundy County Board of Review's decision, you have the right to appeal to the Illinois Property Tax Appeal Board (PTAB) within 30 days of the postmark date on the Board of Review's written decision notice. PTAB is a state-level quasi-judicial body that provides an unbiased forum to contest property assessments. To file a PTAB appeal, you must submit the appropriate petition form (residential, commercial, industrial, or farm) along with all written and documentary evidence supporting your claim. There is no filing fee for PTAB appeals. You can obtain forms from the PTAB office at 401 South Spring, Room 402, Springfield, IL 62706, or download them from the PTAB website. The 30-day deadline is strict—missing it means losing your right to appeal for that tax year. PTAB appeals typically take several months to resolve, and you must continue paying your property taxes while the appeal is pending.

When will I receive my property assessment notice in Grundy County?

In Grundy County, assessment notices are mailed in the spring each year, typically reaching homeowners' mailboxes by mid-April. Your assessment notice includes both your property's market value and assessed value (which is 33.33% of market value), along with an estimate of your annual property tax bill. It's crucial to review this notice carefully as soon as you receive it because it triggers the timeline for filing an appeal. You should compare your assessed value to similar properties in your neighborhood and verify that all property characteristics are accurate. If you believe your assessment is too high, you need to immediately begin gathering evidence and preparing your appeal, as the filing deadline typically falls in late November—giving you about six to seven months to build your case. You can look up your property information year-round at grundyil.devnetwedge.com to track changes and compare your assessment to neighboring properties.

What happens at a Grundy County Board of Review hearing?

At a Grundy County Board of Review hearing, you'll present your case before a three-member Board that has the authority to lower, raise, or maintain your property's assessed value. The Supervisor of Assessments serves as the Board clerk and is present at all hearings. During the hearing, you'll have the opportunity to explain why you believe your assessment is too high, presenting your evidence such as comparable sales, photographs, appraisals, or documentation of unequal assessment. The Board may ask questions about your property, your evidence, or your valuation conclusions. The hearing is less formal than a court proceeding, but you should still be organized and professional in your presentation. After hearing your case and reviewing your evidence, the Board will issue a written decision, typically mailed within several weeks. If the Board reduces your assessment, the savings will be reflected in your next tax bill. If you disagree with the Board's decision, you have 30 days from the postmark date to file an appeal with the Illinois Property Tax Appeal Board (PTAB).

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 →

More Illinois Counties

Champaign County (Champaign)Cook County (Chicago)DeKalb County (Sycamore)DuPage County (Naperville)Kane County (Aurora)Kankakee County (Kankakee)

← All Illinois property tax appeal info

Sources: https://www.grundycountyil.gov/services/assessor/ | https://grundyil.devnetwedge.com/ | https://www.ownwell.com/trends/illinois/grundy-county | https://tax.illinois.gov/localgovernments/property/appeals.html | https://www.grundycountyil.gov/services/assessor/property_tax_relief.php | https://en.wikipedia.org/wiki/Grundy_County,_Illinois | https://www.ptab.illinois.gov/

Last verified: 2026-03-05