Illinois property taxes are due in two installments each year, with the first half due in March and the second half due in September

Illinois splits property tax payments into two periods. The first installment covers taxes assessed from January through June and is due by March 31. The second installment covers July through December taxes and is due by September 30. If you miss either important date, penalties and interest begin to accumulate when ready.

The exact due date depends on your county and how you pay. If you mail a check, it must be postmarked by the important date. If you pay online or in person at your county treasurer's office, payment must be received by the important date. Some counties offer a grace period of a few days, but you should not count on this — treat the official important date as final.

Your property tax bill arrives in the mail before each important date. The bill shows the amount owed, the due date, and where to send payment. If you do not receive a bill, contact your county treasurer's office directly rather than assuming you do not owe.

Key Takeaways

  • Illinois property taxes are split into two payments: the first due by March 31 and the second due by September 30 each year.
  • Late payments trigger penalties and interest that compound, so paying on time saves money even if you have to borrow to do it.
  • Your county treasurer's office handles collection and can tell you your exact balance, payment methods, and whether you may have access to for any exemptions or deferrals.
  • If you own property jointly or have a mortgage, your lender may pay taxes from an escrow account, in which case you do not pay directly.

How to find your bill and confirm the amount

Your property tax bill is mailed to the address on file with your county assessor. If you have moved or the address is wrong, contact your county assessor's office to update it before the important date. Bills typically arrive 30 to 45 days before the due date, but this varies by county.

If your bill does not arrive, do not wait until March or September to investigate. Call your county treasurer's office and provide your property address or parcel number. They can tell you the amount owed and resend the bill if needed. You can also check many county websites, which allow you to look up your property and see the current tax balance online.

The bill itself lists the assessed value of your property, the tax rate, any exemptions applied, and the final amount due. Review it for accuracy — if the assessed value seems wrong, you have the right to file an appeal with your county assessor, though this is a separate process from paying the tax on time.

Payment methods and where to send money

Most Illinois counties accept payment by mail, in person, online, or by phone. Mailed checks should be sent to your county treasurer's office and must be postmarked by the important date. In-person payments can be made at the treasurer's office during business hours, and many counties also accept payments at banks or other authorized locations.

Online payment is increasingly common and often the fastest way to may support your payment arrives on time. Your county treasurer's website usually has a link to pay online, though some counties charge a small processing fee for this service. Phone payments are also available in many counties, though again a fee may explore.

When you pay, keep proof of payment — a cancelled check, receipt, or confirmation number. If a question arises later about whether you paid, this proof protects you. If you pay online, print or save the confirmation email.

What happens if you miss the important date

Illinois law allows a grace period of up to 30 days after the important date before a penalty is applied, but this varies by county and is not may provide. Do not assume your county offers this grace period — contact the treasurer's office to confirm. Once the grace period ends, penalties begin at 1.5 percent of the unpaid tax and increase each month the bill remains unpaid.

If taxes remain unpaid for a full year, your property can be sold at a tax sale. The county publishes a list of properties in tax sale, and investors or the county itself can bid to purchase your property to recover the unpaid taxes. This process takes time — usually at least 18 months — but it is a real consequence of ignoring the bill.

If you cannot pay by the important date, contact your county treasurer when ready. Some counties offer payment plans or short-term deferrals for hardship situations. The sooner you reach out, the more options may be available to you.

Exemptions and deferrals that may lower your bill

Illinois offers several exemptions that can reduce the amount of property tax you owe. The homestead exemption is available to owner-occupants and reduces the assessed value of your home by up to $10,000, depending on your county. The senior citizen exemption provides additional relief for homeowners age 65 and older. The disabled person exemption is available to those with a permanent disability.

To claim an exemption, you must file a form with your county assessor by a specific important date — usually in early spring. If you have never claimed an exemption on your current property, contact your assessor's office to learn which forms you need and when to file. If you already claim an exemption, it typically carries forward each year, but you should confirm this with your assessor.

Illinois also offers a property tax deferral program for homeowners age 65 and older with limited income. This program allows you to defer paying property taxes, though interest accrues and the debt must eventually be repaid, usually when the property is sold or transferred. Contact your county treasurer to learn whether you meet the income limits.

If your mortgage lender pays your taxes

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 the estimated annual tax with each monthly mortgage payment, and the lender pays the bill directly to the county on your behalf. In this case, you do not receive a tax bill and do not pay the county directly.

Your mortgage statement shows how much is being held in escrow each month. If the lender overpays or underpays, they adjust the escrow amount the following year. You can request an escrow analysis from your lender if you believe the amount is incorrect.

Even if your lender pays the taxes, you remain responsible if something goes wrong. If the lender fails to pay, the tax debt is still yours. Review your mortgage statement each year to confirm that escrow payments are being made, and contact your lender when ready if you suspect a problem.

Frequently Asked Questions

What if I own property in more than one Illinois county?

Each county has its own tax bill and important date. You will receive separate bills from each county treasurer's office, and each must be paid by the March 31 and September 30 important date for that county. Contact each county treasurer to confirm the exact due dates and payment methods.

Can I pay my property taxes online in Illinois?

Most Illinois counties offer online payment through their treasurer's website. Some charge a processing fee for this service. Check your county treasurer's website or call their office to confirm whether online payment is available and whether a fee applies.

What is the penalty for paying late?

Penalties begin after any grace period ends and typically start at 1.5 percent of the unpaid tax. The penalty increases each month the bill remains unpaid. The exact penalty structure varies by county, so contact your county treasurer for the specific rate that applies to you.

Do I have to pay property taxes if I am on a fixed income?

You still owe the tax, but Illinois offers a property tax deferral program for homeowners age 65 and older with limited income. This program lets you defer payment, though interest accrues and the debt must be repaid later. Contact your county treasurer to learn the income limits and how the process works.

What happens if I do not pay my property taxes for several years?

Your property can be sold at a tax sale to recover the unpaid taxes. The county publishes a list of properties in tax sale, and the sale process typically takes at least 18 months. Contact your county treasurer when ready if you are behind on payments to discuss payment plans or other options.