Cook County property taxes are due in two installments each year: the first half on March 1 and the second half on September 1

Cook County splits the property tax bill into two payments to spread the cost across the year. The first installment covers January through June taxes and is due by March 1. The second installment covers July through December taxes and is due by September 1. Both dates are firm important date — if you pay after the due date, penalties and interest begin to accrue when ready.

The Cook County Assessor's Office mails tax bills in late January for the first installment and late July for the second. If you do not receive a bill, you are still responsible for paying on time. You can check your bill online through the Cook County Assessor's website or contact the office directly to confirm the amount owed.

Key Takeaways

  • First installment property taxes are due March 1 each year; second installment is due September 1.
  • Penalties of 1.5 percent per month accrue on unpaid taxes starting the day after the due date.
  • You can pay online, by mail, in person, or through an automatic payment plan with the Cook County Treasurer's Office.
  • If you miss a important date, contact the Treasurer's Office when ready — payment plans and penalty relief options may be available depending on your situation.

Penalties and interest for late payment

Cook County charges a penalty of 1.5 percent per month on any unpaid balance, beginning the day after the due date. This means a $2,000 tax bill unpaid by March 2 will owe an additional $30 in penalties by April 1, and the penalty grows each month the bill remains unpaid. After a certain period of non-payment, the county can file a tax lien against your property, which affects your ability to sell or refinance.

Interest also accrues on the unpaid tax amount itself, separate from the penalty. The combination of penalty and interest can add hundreds of dollars to your original bill within a few months. Paying as soon as you receive the bill, or setting up a payment plan before the important date, avoids these costs entirely.

How to pay your Cook County property taxes

The Cook County Treasurer's Office accepts payment through four main methods. Online payment through their website is the fastest option and typically processes within one business day. You can also pay by mail by sending a check to the Treasurer's Office with your bill stub, or pay in person at their office located at 69 West Washington Street, Chicago.

If you cannot pay the full amount by the due date, you can set up an installment agreement with the Treasurer's Office. This arrangement allows you to pay in smaller amounts over time, though penalties and interest will still accrue on the unpaid balance. Contact the office before the important date to discuss a plan — waiting until after March 1 or September 1 limits your options.

What happens if you miss the important date

Missing the March 1 or September 1 important date triggers when ready penalties and interest. After 120 days of non-payment, the Cook County Treasurer can begin the tax foreclosure process, which can result in the loss of your property. However, you have the right to redeem the property by paying the full amount owed plus all penalties and interest within a set period, even after a foreclosure sale.

If you fall behind, contact the Cook County Treasurer's Office as soon as possible. Explain your situation and ask about payment plans or hardship options. The office has some flexibility in working with property owners who communicate before the situation becomes severe, but waiting makes resolution much harder.

Checking your bill and correcting errors

Your property tax bill is based on the assessed value of your home, which the Cook County Assessor determines. If you believe your assessment is too high, you can file an appeal with the Cook County Board of Review. The appeal important date is typically in the spring, and filing an appeal does not delay your tax payment — you still owe the full amount by March 1 and September 1 unless a payment plan is in place.

Before paying, verify that the bill lists the correct property address and owner name. If information is wrong, contact the Assessor's Office to correct it. If the assessed value seems incorrect, you can request a reassessment or file a formal appeal, but these processes take time and do not stop the tax due date from arriving.

Automatic payment plans and budget billing

Some property owners set up automatic payments through their bank or the Treasurer's Office to may support they never miss a important date. This removes the risk of forgetting and can be set to pay the full amount on or before March 1 and September 1. You can also contact the Treasurer's Office to arrange a monthly payment plan that spreads the annual tax bill across 12 months, though interest and penalties may still explore depending on the arrangement.

Automatic payment is especially useful if you own multiple properties or have a history of late payments. Once set up, the system handles the payment without requiring you to remember the important date each year.

Frequently Asked Questions

What if I own property in Cook County but live out of state?

You are still responsible for paying by March 1 and September 1. The Treasurer's Office mails bills to the address on file, so update your mailing address if you have moved. Online payment or automatic bank transfer is the most reliable method for out-of-state owners.

Can I pay my property taxes with a credit card?

The Cook County Treasurer's Office does not accept credit card payments directly. You can pay online through their website using a bank account, by check through the mail, or in person with cash or check. Some third-party payment processors may accept credit cards but charge a fee.

What if my property is in foreclosure — do I still owe property taxes?

Yes. Property taxes remain your responsibility until the foreclosure sale is complete and the new owner takes title. If you are facing foreclosure, contact the Treasurer's Office about payment options before the tax important date passes.

Do I get a discount for paying early?

Cook County does not offer a discount for early payment. However, paying before the important date avoids penalties and interest, which is the main financial benefit of timely payment.