Illinois real estate taxes are due twice a year, in June and September

Illinois splits property tax payments into two installments. The first installment is due June 1, and the second is due September 1. Both dates are firm important date — if your payment arrives after these dates, you will owe a penalty. The exact amount you owe depends on your county assessor's valuation of your property and your local tax rate, which varies by county and municipality.

Your county treasurer sends a tax bill in the mail before each due date. The bill shows what you owe for that installment, where to send payment, and payment options. If you do not receive a bill, contact your county treasurer's office directly — not receiving the bill does not erase the debt or extend the important date.

Penalties for late payment start at 1.5 percent of the unpaid amount if you pay between 1 and 30 days late. The penalty increases to 3 percent if you pay 31 to 60 days late, 5 percent for 61 to 90 days late, and 10 percent for anything over 90 days late. After a certain period of non-payment, the county can place a tax lien on your property or sell the tax certificate to a third party, which can eventually lead to a forced sale of your home.

Key Takeaways

  • Illinois property taxes are due twice yearly: June 1 for the first installment and September 1 for the second.
  • Your county treasurer mails a bill before each important date showing the amount owed and payment methods.
  • Late payments trigger penalties starting at 1.5 percent and climbing to 10 percent depending on how many days overdue the payment is.
  • If taxes remain unpaid for an extended period, the county can place a lien on your property or sell the tax certificate, potentially leading to loss of ownership.

How to pay your Illinois property taxes

Most county treasurers accept payment by mail, in person, or online. Check your tax bill or your county treasurer's website to see which methods are available in your county. Online payment is often the fastest and most convenient option — you can pay from home and receive when ready confirmation.

If you pay by mail, send your check or money order to the address listed on your bill at least one week before the due date to account for postal delays. Payment received after the due date is considered late, even if you mailed it on time. Some counties charge a small fee for online or credit card payments, so compare the cost of the fee against the cost of a late penalty before choosing your method.

If you own property in multiple counties, each county sends its own bill and has its own due date. You cannot combine payments or pay one county to cover another. Keep copies of your payment confirmations for your records.

What happens if you cannot pay by the due date

If you know you will miss a important date, contact your county treasurer when ready. Some counties offer payment plans or short extensions, though these are not may provide and must be arranged before the due date passes. Waiting until after June 1 or September 1 to ask for help means you will already owe penalties.

If you are struggling with property taxes because of financial hardship, look into whether your county offers a homestead exemption or senior exemption, which can lower your assessed value and reduce future tax bills. These are not retroactive — they reduce what you owe going forward, not what you already owe. You must explore during a specific window, usually in the spring.

If you have already fallen behind, some counties have tax relief programs or payment plans for people in arrears. Contact your county treasurer's office to ask what options exist in your area. The longer you wait, the more penalties accumulate and the harder it becomes to catch up.

Understanding your property tax bill

Your Illinois property tax bill lists several pieces of information. The assessed value is what your county assessor estimates your property is worth — this is not the same as the market value or what you paid for it. The tax rate (called the "levy") is set by your local government and varies by municipality. The bill multiplies the assessed value by the tax rate to arrive at your total tax bill for the year, then divides it in half for the two installments.

If you believe your assessed value is too high, you can file a formal objection called a "complaint" with your county assessor's office. The important date to file is usually in the spring, before the tax year begins. Filing a complaint does not automatically lower your assessment — you must present evidence that the value is incorrect, such as a recent appraisal or comparable sales in your neighborhood.

Your bill also shows any exemptions you are receiving, such as a homestead exemption or senior exemption. If you think you may have access to for an exemption you are not receiving, contact your assessor's office to learn how the process works.

Penalties, liens, and what comes next

If your payment is late, the penalty is calculated on the unpaid amount and added to your debt. A $2,000 installment paid 45 days late, for example, would owe a 5 percent penalty ($100) on top of the original $2,000. The penalty compounds with each missed important date, so falling behind on one installment and then missing the next one creates a much larger debt very quickly.

If taxes remain unpaid for approximately one year, your county treasurer can sell a tax certificate to an investor or the county itself. The holder of the tax certificate has the right to foreclose on your property if the taxes are not paid within a set period (usually three years, though this varies by county). Foreclosure means you lose ownership of your home.

Before a tax sale or foreclosure happens, you have the right to redeem the property by paying the full amount owed plus interest and costs. Once a foreclosure is filed, however, the process moves quickly and the cost to redeem rises significantly. If you receive notice that a tax certificate has been sold on your property, contact your county treasurer or a real estate attorney when ready.

Setting up automatic payments or escrow

If you have a mortgage, your lender may require you to pay property taxes through an escrow account. This means you pay a portion of your estimated annual taxes each month with your mortgage payment, and the lender pays the county on your behalf when the bill comes due. This protects the lender's interest in the property and ensures taxes are paid on time.

If you do not have a mortgage or your lender does not require escrow, you can set up automatic payments directly with your county treasurer. Most counties allow you to authorize a monthly transfer from your bank account, which the treasurer holds and applies to your tax bill when it is due. This removes the risk of forgetting a important date and helps you budget for the expense throughout the year.

Ask your county treasurer whether automatic payment is available and whether there is a fee. Some counties offer it free; others charge a small processing fee. Even with automatic payment, check your bill when it arrives to confirm the amount is correct and the payment was applied.

Finding your county treasurer and getting help

Your county treasurer's office handles all property tax matters in your county. You can find contact information by searching "[your county name] treasurer" online or by calling your county clerk's office. Most treasurers have websites that show payment methods, important date, and frequently asked questions specific to your county.

If you need help understanding your bill, have questions about payment plans, or want to know whether you may have access to for an exemption, call your county treasurer directly. Staff can explain your bill, answer questions about important date, and tell you what options are available if you are behind. This is a free service — do not pay anyone to help you with this.

If you are facing foreclosure or have a complex tax situation, consider consulting a real estate attorney or a nonprofit housing counselor. These professionals can review your options and help you understand the steps ahead.

Frequently Asked Questions

What if I did not receive my property tax bill in the mail?

Contact your county treasurer's office when ready. Not receiving the bill does not extend the important date or erase the debt. The treasurer can tell you the amount owed and provide payment instructions. You may also be able to view your bill online through the county website.

Can I pay my property taxes in one lump sum instead of two installments?

Some counties allow you to pay the full year's taxes at once, usually by the first important date (June 1). Contact your county treasurer to ask whether this option is available and whether there is any discount for paying early. If you pay early, you may receive a small reduction in the amount owed.

What is the difference between assessed value and market value?

Assessed value is what your county assessor estimates your property is worth for tax purposes. Market value is what your property would sell for on the open market. Assessed value is usually lower than market value, but it is not always accurate. If you believe the assessed value is wrong, you can file a complaint with your assessor's office during the spring filing window.

Can I deduct Illinois property taxes on my federal income tax return?

Yes, you can deduct state and local property taxes on your federal return, up to a combined limit of $10,000 per year for all state and local taxes (including income tax and sales tax). Consult a tax professional or the IRS website for details on how to claim this deduction.

What happens if a tax certificate is sold on my property?

The certificate holder has the right to foreclose on your property if taxes remain unpaid. You can stop the foreclosure by paying the full amount owed plus interest and costs. If you receive notice that a certificate has been sold, contact your county treasurer or an attorney right away to understand your options and timeline.