A Cook County tax bill depends on two things you can do something about: the exemptions on your home, and the assessed value the county puts on it. Exemptions are the easy part. Most homeowners qualify for at least one, and many renew automatically. Appeals take a little more work, but filing is free.
At a glance
- Homeowner exemption
- Takes $10,000 off your home's EAV [1]
- Senior exemption (65+)
- Takes another $8,000 off EAV [2]
- Senior freeze
- Freezes EAV if household income is $65,000 or less [3]
- Tax year 2025 due dates
- April 1, 2026 and October 1, 2026 [4]
- Appeal cost
- Free; usually 30 days after your reassessment notice [5]
How exemptions work
Cook County exemptions don’t come off your bill in dollars. They lower your home’s equalized assessed value (EAV) . Your savings are the exemption amount times your local tax rate. So a $10,000 exemption saves more in a town with a high tax rate than in one with a low rate.
| Exemption | Who qualifies | What it does |
|---|---|---|
| Homeowner | You own and live in the home as your main residence (house, townhouse, condo, co-op, or a building of up to 6 units) | Cuts EAV by $10,000 (since tax year 2017) |
| Senior Citizen | You're 65 or older during the tax year and owned and lived in the home on January 1 | Cuts EAV by $8,000 |
| Senior Freeze | 65 or older, owned and lived in the home on January 1, household income of $65,000 or less | Freezes EAV at a base-year level; reapply every year |
Homeowner exemption
If the home is your main residence, you can get the homeowner exemption. It reduces your EAV by $10,000 [1]. New owners apply through the Cook County Assessor’s Office. If you already have it and haven’t sold, it renews automatically [1].
Senior exemption
If you’re 65 or older during the tax year, and you owned and lived in the home on January 1, you can also get the senior exemption. It cuts your EAV by another $8,000 [2]. There’s no income limit for this one.
Senior freeze
The senior freeze is for seniors with lower incomes. It locks your EAV, so your taxable value doesn’t climb when assessments go up. Your tax rate can still change, so the bill itself isn’t frozen. To qualify you need total household income of $65,000 or less, and you have to reapply every year [3].
Missed an exemption in an earlier year? The Assessor processes late applications as a certificate of error , which can correct past bills [9].
When the bills are due
Cook County bills come in two installments a year. The Treasurer posts each due date once it’s set.
| Tax year | Installment | Due date |
|---|---|---|
| 2025 | First | April 1, 2026 |
| 2025 | Second | October 1, 2026 |
| 2024 | Second | December 15, 2025 |
| 2024 | First | March 4, 2025 |
If you’ve missed a due date, pay as soon as you can and contact the Treasurer’s Office: late payments add interest.
How to appeal your assessment
If you think the county has valued your home too high, there are two free chances to appeal each time your township is open.
- Cook County Assessor. You usually have 30 days after your reassessment notice to file, and the notice prints the deadline. Filing is free and can be done online. You don’t need to hire anyone [5]. Miss it, and you can try again the next time your township opens.
- Cook County Board of Review. This is a separate office that hears appeals township by township, each with its own filing window. You can file online through the Board’s portal [7].
- Beyond the county. If you disagree with the Board of Review’s decision, you can take it to the state Property Tax Appeal Board [8] or to court. A lawyer can help with these later stages.
What helps an appeal
- Recent sale prices of similar homes nearby.
- Mistakes in the Assessor’s description of your home (square footage, number of bathrooms, a basement you don’t have).
- Your own purchase price, if you bought recently.
- Photos of damage or problems that lower the value.
Sources
- Cook County Treasurer: Homeowner Exemption
- Cook County Treasurer: Senior Citizen Homestead Exemption
- Cook County Treasurer: Senior Citizen Assessment Freeze Exemption
- Cook County Treasurer: Important dates (installment due dates)
- Cook County Assessor: Appeals
- Cook County Assessor: Assessor Kaegi praises passage of property tax relief for senior homeowners (Nov. 4, 2025)
- Cook County Board of Review
- Illinois Property Tax Appeal Board
- Cook County Assessor: Exemptions
Common questions
How much does the homeowner exemption save in Cook County?
It takes $10,000 off your home's equalized assessed value (EAV). Your actual savings are that $10,000 times your local tax rate, so they vary by town.
When are Cook County property taxes due in 2026?
For tax year 2025, the first installment was due April 1, 2026 and the second installment was due October 1, 2026. Check the Treasurer's site for the next dates.
Do I need a lawyer to appeal my Cook County assessment?
No. Appealing to the Assessor is free and can be done online, and the Assessor says you don't need to hire anyone to file for you.