Chicago Property Tax Calculator: How Are Property Taxes Calculated in Illinois?

Illinois has a statewide average effective property tax rate of 2.07%, a figure nearly double the national average. If you're trying to estimate your property tax bill or understand why your annual property taxes are so high, view our Property Tax Calculator below. This tool gives you an instant property tax estimate based on your home value and location.

For property owners and businesses alike, knowing how property taxes are calculated helps with financial planning. Whether you own a residential property or manage a commercial building, this guide breaks down the property tax calculation process in Illinois.

The Three Components: How Our Property Tax Calculator Works

Property taxes in Illinois are calculated using a simple formula with three key components: assessed value, tax rate, and your final tax bill. Here's how each element affects what you pay:

Assessed Value

The assessed value is the foundation of your property tax calculation. Local government authorities evaluate your property and consider factors like improvements, market trends, and property type. In Illinois, the assessed value for most properties equals 33.33% (one-third) of the property's market value. Some counties apply an equalization factor to ensure fair assessments across different areas, which adjusts your property's assessed value.

For example, if your home's market value is $300,000, your assessed value would be $100,000 ($300,000 × 33.33%).

Tax Rate

The tax rate (also called the mill rate or millage rate) is a percentage set by local taxing districts, including your county, municipality, school district, and other local governments. Each taxing district sets its own rate based on the revenue needed to fund services like education, public safety, and infrastructure.

Property tax rates vary based on location; for example, Cook County typically has different rates than surrounding counties like DuPage, Lake, or Will. The combined rates from all taxing districts in your area create your total tax rate.

For instance, if your total tax rate is 7.5%, this represents $7.50 in taxes for every $100 of assessed value.

Tax Bill

Your property tax bill is the final amount you owe, calculated by multiplying your assessed value by your tax rate.

Complete example:

• Home's market value: $300,000
• Assessed value: $100,000 (one-third of market value)
• Total tax rate: 7.5%
• Annual property tax: $7,500 ($100,000 × 7.5%)

This means your property taxes would equal approximately $625 per month's mortgage payment if escrowed.

How Lewis.cpa Fights Your Unfair Tax Assessment

After reviewing your assessment record, you can determine if your property tax assessment is fair using two approaches:

• Compare Market Value: Match your property's fair market value with recent sales of comparable properties in your area. This method works best if you recently purchased your home under normal conditions or received a professional appraisal.
• Compare Assessed Values: Evaluate your home's assessed value against similar residential properties in your neighborhood. You can get property tax information from your township assessor, county assessor, or the CCAO (Cook County Assessor's Office).

What to Do About an Unfair Assessment

If you believe your assessment is incorrect, you have several options:

• Cook County Properties: Request a revision through the county assessor or file a complaint with the Cook County Board of Review.
• Other Counties: Submit a complaint to your county's board of review.
• Further Appeals: If unsatisfied, appeal to the Illinois Property Tax Appeal Board or file a tax objection complaint in circuit court.

Important: Act quickly, as deadlines for filing are on your "notice of assessment change" form. Once you receive your tax bill, contesting your assessment becomes difficult or even impossible.

Property Tax Exemptions: Reduce Your Tax Bill with Expert Help

Illinois offers numerous property tax exemptions that can significantly reduce your annual property taxes. These exemptions lower your taxable value, which directly decreases what you pay. At Lewis.cpa, we help clients identify and secure every exemption they qualify for.

Homestead Exemptions for Residential Property

Illinois offers several key Homestead Exemptions to reduce the assessed value of a primary residence and significantly lower your tax bill.

• General Homestead Exemption: Available to homeowners who live in their primary residence. This exemption reduces assessed value by $10,000 in Cook County and $6,000 in other counties, providing substantial savings on your property tax bill.
• Senior Citizens Homestead Exemption: For homeowners aged 65 and older living in their primary residence. Offers a $5,000 reduction in assessed value ($8,000 in Cook County), helping seniors manage their property tax liability.
• Additional residential exemptions may apply based on your situation, including exemptions for veterans, disabled persons, and homeowners making energy-efficient improvements.

Business Property Tax Relief

Illinois provides several exemptions to support businesses, such as:

• Enterprise Zone Property Tax Abatement: Encourages investment in designated enterprise zones.
• High Impact Business Property Tax Incentive: Attracts and retains major employers.
• Pollution Control Facilities Exemption: Benefits businesses with environmentally responsible practices.

These exemptions provide direct financial relief and help businesses invest in growth. Keep in mind that application forms and eligibility requirements vary depending on the exemption type and location.

Illinois Property Tax Extension Limitation Law (PTELL)

PTELL limits how much property taxes can increase due to rising property values. Under this law, revenue growth cannot exceed the inflation rate (Consumer Price Index) or 5%, whichever is lower. This limit helps control annual property tax increases, though Illinois property taxes remain among the highest in the nation.

Even with PTELL protections, the average property tax rate across Illinois stays well above other states. Your county, municipality, and school district rates will impact your actual taxes.

Lewis.cpa: Your Trusted Partner for Property Tax Relief

At Lewis.cpa, our firm has 25+ years of experience serving individuals and businesses throughout Illinois. Whether you're trying to calculate property taxes for a home purchase, reduce your current tax bill, or understand how property taxes compare across different areas, you can rely on us to provide the expertise you need.

Contact us today at (630) 548-9600 to get a personalized property tax assessment and discover how much you could save.