DuPage County property tax due dates for 2026 are June 1 and September 1, covering the 2025 tax year because Illinois bills property taxes a year in arrears. The county mailed 321,773 bills on April 29, 2026, giving owners roughly a month to review before the first installment comes due.1DuPage County. DuPage County Treasurer Both payment coupons arrive in the same envelope, so keep the full bill after paying in June. You will need the second coupon in September.
Why the Two Installments Differ in Amount
The June payment is not calculated from your current assessment. It equals 55% of last year’s total tax bill and acts as an estimated payment while the county finishes current-year assessments.2Illinois Department of Revenue. What Should I Do if I Have Not Received My Property Tax Bill The September payment settles the balance once the updated rate and exemptions are applied. That second number can land noticeably above or below the first depending on how assessments and rates moved.
Ways to Pay
DuPage offers four channels. Each has a quirk worth knowing before you pick.
Online
The Treasurer’s ePay portal takes electronic checks and Visa, MasterCard, or Discover cards. Card payments carry a 2.10% convenience fee charged by the processor, and none of it goes to the county.3DuPage County. ePay Your Real Estate Taxes On a $5,000 installment, that is roughly $105 extra. eCheck avoids the surcharge.
By Mail
Through October 31, 2026, mail your payment to the lockbox using the pre-addressed envelope: DuPage County Collector, Bill Payment Center, P.O. Box 4203, Carol Stream, IL 60197. After October 31, mail goes directly to the Treasurer’s Office at 421 N. County Farm Road, Wheaton, IL 60187. Include the correct installment coupon and make the check payable to “DuPage County Collector.”4DuPage County. Paying Real Estate Taxes By Mail
The U.S. Postal Service postmark is proof of timely payment, so a check postmarked by the due date is on time even if it arrives later.5DuPage County. Tax Information One detail trips people up: after October 31, 2026, personal checks are no longer accepted. From that point forward, pay by cashier’s check, money order, or cash.4DuPage County. Paying Real Estate Taxes By Mail
At a Participating Bank
Dozens of banks in the county accept property tax payments from May 1 through September 1, 2026. Bring your coupon. Some branches accept copies and some do not. The Treasurer’s website lists participating branches by city.6DuPage County. Banks in DuPage County Banks stop taking payments after the second installment deadline, so this channel is only open during the regular collection window.
In Person
Starting May 1, 2026, you can pay at the Treasurer’s Office, 421 N. County Farm Road in Wheaton, Monday through Friday from 8:00 a.m. to 4:30 p.m. Cash, check, and credit or debit cards are all accepted at the counter.3DuPage County. ePay Your Real Estate Taxes
Every payment method requires your Property Index Number (PIN), printed on the top of your bill as “Parcel Number.” If you mislaid the bill, look up your PIN by address on the county’s Property Lookup Portal.7DuPage County. Supervisor of Assessments – Property Lookup Portal When mailing a check, write the PIN on its face so the payment reaches the right parcel.
If Your Mortgage Escrow Pays the Bill
Many homeowners have taxes paid through a mortgage escrow account, meaning the lender sends the money to the county. The due dates are the same, but you should verify each installment actually posted. The simplest check is to search your PIN on the Treasurer’s online portal after each deadline and confirm the installment shows paid.
If the county notifies you that taxes are unpaid despite having escrow, contact your mortgage servicer right away. The Consumer Financial Protection Bureau recommends putting the request in writing and sending a formal notice of error with a copy of the tax bill. Tell the county you are working with your servicer so collection steps do not advance while the error is being fixed.8Consumer Financial Protection Bureau. What Should I Do if I Get a Tax Bill From the City or County Saying That My Mortgage Servicer Did Not Pay My Taxes
What Happens if You Pay Late
Interest starts the day after the deadline. Under Illinois law, unpaid DuPage County property taxes accrue interest at 1.5% per month, and a partial month counts as a full month.9Illinois General Assembly. 35 ILCS 200/21-15 – General Tax Due Dates; Default by Mortgage Lender The rate is set by statute, and the Treasurer’s Office cannot reduce or waive it.
Put in dollar terms: on a $5,000 unpaid installment, one month of interest adds $75. Six months adds $450. Interest is charged on the full unpaid balance rather than a declining one, so the cost climbs fast if the bill sits.
If the Bill Goes Unpaid
Unpaid taxes eventually reach a tax sale. For 2025 taxes payable in 2026, the DuPage County annual tax sale is scheduled to begin November 19, 2026. If either installment remains delinquent in early October, your name and parcel number are published in local newspapers on the delinquent tax list, and $10 is added to your balance to cover publication and certified mailing. The last day to pay delinquent 2025 taxes and avoid the sale is November 18, 2026, at 4:30 p.m., and only cashier’s check, cash, or money order is accepted at that point.10DuPage County. Tax Sale Information
At the sale, the county does not sell your home. It sells the tax debt to a third-party buyer, who pays the delinquent amount in exchange for a lien. You still own the property, but you now owe the tax buyer the full amount plus interest and legal fees. Illinois law gives most owners two and a half years from the sale date to redeem by paying everything owed. For vacant non-farm land, commercial property, and buildings with seven or more residential units, the redemption window is one year. If you do not redeem in time, the tax buyer can petition a court for a tax deed, which transfers ownership.11DuPage County. Tax Redemption