📚 Illinois Property Tax Guide 2026

How Illinois Property Tax Works

In Illinois, your property tax starts with the assessed (taxable) value of your home, which is then multiplied by the local tax rate. The state's assessment basis is 33 1/3% of market value for most residential property (the state's standard assessment level), then multiplied by local tax rates. The average effective property tax rate in Illinois is approximately 1.97% of home value, though your actual rate depends on your county, city, school district, and any exemptions you claim.

This guide explains the system in plain language so you can check your bill, claim every exemption you qualify for, and appeal if your assessed value looks wrong.

Illinois Assessment & Revaluation

• Assessment basis: 33 1/3% of market value for most residential property (the state's standard assessment level), then multiplied by local tax rates.
• Revaluation cycle: on a 3- or 4-year reassessment cycle by county (Cook County uses a triennial system by township).
• Who sets the rate: Tax rates are set locally by your county, city, school district, and any special districts, then applied to your assessed value.
• Your bill: Assessed value × total local rate − exemptions = tax due.

Illinois County Tax Rates (2025)

The table below shows approximate average effective tax rates and typical annual tax for representative Illinois counties. Rates vary by locality because of different voter-approved levies and district boundaries. Figures are estimates for illustration; verify the exact numbers with your county assessor.

Homestead Exemption in Illinois

Illinois has no broad statewide homestead exemption, but seniors, disabled persons, and veterans can receive a freeze that caps the assessed value (and therefore the bill) from rising.

• Seniors: The Senior Citizens Real Estate Tax Deferral lets qualifying seniors defer all or part of the tax; a separate Senior Homestead exemption of $5,000 to $8,000 of assessed value also applies in many counties.
• Veterans & disabled: Disabled veterans (30%+ service-connected) and surviving spouses receive a reduction of assessed value, scaling up to a full exemption at 100% disability.
• File every year: Most Illinois exemptions must be applied for with the county assessor; they do not appear automatically on a new purchase.

How to Lower Your Illinois Property Tax

1. File an Assessment Appeal

If your assessed value is higher than what similar Illinois homes sell for, you can appeal. The deadline is within 30 days of the reassessment notice, to the county Board of Review (and then PTAB). Gather recent comparable sales and the assessed values of nearby homes, then present them to your local board. A successful appeal lowers the base value and therefore every future bill.

2. Claim Every Exemption

Verify you receive all eligible relief: the homestead exemption, the senior/disabled programs, and any veteran exemption. Contact your county assessor to confirm you are not missing a saving you qualify for.

3. Watch Reassessment Triggers

Improvements, a change of ownership, or a periodic revaluation can raise your assessed value. Knowing your county's on a 3- or 4-year reassessment cycle by county (Cook County uses a triennial system by township) helps you predict and prepare for bill changes rather than being surprised by them.

4. Use Our Calculator

Model the dollar result before you act. Our property tax calculator and the exemption calculator show how exemptions and rates change your bill in Illinois.

Property Tax Payment in Illinois

Most Illinois homeowners pay property tax through an escrow account included in their monthly mortgage payment, or in installments directly to the treasurer. Missing a deadline adds penalties and interest, so mark your payment dates and watch for the assessment and tax notices each year. If you escrow, your lender forwards the payment — but you should still read the annual notice to catch errors.

Illinois vs. Other States

How does Illinois compare? The points below put the state's system in context:

• vs. Indiana: Illinois's average effective rate of about 1.97% is higher than Indiana's ~0.85%, and Indiana also has a broad state income tax. Homeowners moving between the two states should re-model their bill rather than assume it stays the same.
• vs. Missouri: Illinois's average effective rate of about 1.97% is higher than Missouri's ~0.91%, and Missouri also has a broad state income tax. Homeowners moving between the two states should re-model their bill rather than assume it stays the same.
• vs. Wisconsin: Illinois's average effective rate of about 1.97% is higher than Wisconsin's ~1.50%, and Wisconsin also has a broad state income tax. Homeowners moving between the two states should re-model their bill rather than assume it stays the same.

Frequently Asked Questions — Illinois

What is the average property tax rate in Illinois?

The average effective rate is about 1.97% of home value, but your actual rate depends on your county, city, and school district. A home in a high-levy district can owe noticeably more than the same-priced home in a lower-levy district.

How is property assessed in Illinois?

33 1/3% of market value for most residential property (the state's standard assessment level), then multiplied by local tax rates Revaluation follows this schedule: on a 3- or 4-year reassessment cycle by county (Cook County uses a triennial system by township). The assessed value × local rate, minus any exemptions, produces your bill.

Does Illinois have a homestead exemption?

Illinois has no broad statewide homestead exemption, but seniors, disabled persons, and veterans can receive a freeze that caps the assessed value (and therefore the bill) from rising.

What relief is available for seniors and veterans in Illinois?

For seniors: The Senior Citizens Real Estate Tax Deferral lets qualifying seniors defer all or part of the tax; a separate Senior Homestead exemption of $5,000 to $8,000 of assessed value also applies in many counties. For veterans and disabled owners: Disabled veterans (30%+ service-connected) and surviving spouses receive a reduction of assessed value, scaling up to a full exemption at 100% disability.

When is the property tax appeal deadline in Illinois?

You generally must appeal within 30 days of the reassessment notice, to the county Board of Review (and then PTAB). File on time with comparable sales evidence, because missing the window pushes any refund or reduction to the next year.

Does Illinois have a state income tax?

Illinois has a state income tax. This matters because states without an income tax often rely more on the property tax for local services, which is why exemptions and appeals are especially valuable here.

Are Illinois property taxes deductible on federal returns?

Yes, Illinois property tax is deductible on Schedule A, but the $10,000 SALT cap limits the total state and local tax deduction for higher-income homeowners. The deduction lowers your federal tax but does not reduce your Illinois property tax bill itself.

How can I lower my Illinois property tax bill?

Three steps help most owners: (1) appeal an over-assessment using comparable sales; (2) claim every homestead, senior, and veteran exemption you qualify for; and (3) understand your county's revaluation schedule so bill changes never catch you off guard. Our calculators model the savings in dollars.

What Makes Illinois Property Tax Unique

Illinois leans hard on the property tax because it has a flat income tax and caps the statewide rate, which is why effective rates are among the highest in the country

The senior and disabled assessment freezes are the most valuable tool here: once approved, they stop the capped value from climbing even as the neighborhood heats up.

• Illinois has among the highest effective property tax rates in the U.S., especially in the collar counties around Chicago.
• Residential property is assessed at one-third of market value, not full value.
• The main homeowner relief is a senior/disabled/veteran assessment freeze rather than an exemption.
• Cook County's triennial township reassessment drives large year-to-year swings for some owners.

Understanding the Illinois Tax Rate

The headline "1.97%" is an average effective rate — the tax paid as a share of home value. Your real bill is built from several local levies (county, city, school, and special districts) added together and applied to your assessed value after exemptions. Because each district sets its own rate, two neighbors a block apart can owe different amounts. The best way to understand your own rate is to read the annual assessment and tax notice line by line and match each levy to the district that charges it.

Appealing Your Assessment in Illinois

If your assessed value exceeds the market value of comparable Illinois homes, you can appeal. The window is within 30 days of the reassessment notice, to the county Board of Review (and then PTAB). Prepare recent comparable sales, the assessed values of similar nearby homes, and any evidence of condition issues. A successful appeal lowers the taxable base, which then flows through to every future bill — not just the current year.

Worked Illinois Example

A homeowner buys a $350,000 primary residence in Illinois. At the state's average effective rate of about 2.07%, the annual property tax is roughly $7,245. If the home's market value rises over time but the assessment is capped or grows slowly under state rules, the owner keeps the bill far closer to the purchase-year figure than to a tax on full market value — a saving that compounds for as long as they stay. Our calculator models the dollar result once you know your county rate.

Illinois Property Tax for Long-Time & Senior Owners

An Illinois senior should apply for the assessment freeze the year they turn 65, because the freeze only protects value from the date it is granted and does not retroactively undo prior increases. Because Illinois's system is built around the assessed value and local levies, the most valuable habit is simply staying aware of revaluation triggers and filing every exemption you qualify for each year. Reviewing your annual assessment notice is the simplest way to catch an error before it costs you, and it keeps your exemptions current.