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Should You Prepay Illinois Real Estate Tax in 2017 for 2018 Year?

December 20, 2017

With the anticipated passage of the new Tax Reform Act and it's sweeping changes that are effective for the 2018 year, we are once again sending out our email notification to you to consider the prepayment of your personal residence(s) realestate tax in the 2017 year.


We also want to suggest that you also consider a prepayment of your state income taxes in the 2017 year.




The new Tax Reform Act places a combined new limitation of $10,000 for both ofthese "SALT" (State and Local Taxes) starting with the 2018 year. Once again, let us outline some of the "ADVANTAGES" and "NO ADVANTAGES" scenarios to consider before making these prepayments.



1. Acceleration of a tax deduction.


2. The possibility of Federal tax rates decreasing in the 2018 year.


3. The possibility of your taxable income decreasing in the 2018 year.


4. Use of the tax savings (refund) for one full year.


5. If estimated tax payments are made, the fourth quarter, 2017 estimated payments may be reduced.


6. The State of Illinois tax savings - since principal residence real estate taxes are subject to a credit of 5% of the amount paid. (NOT Applicable if your Illinois base income exceeds $500,000 in the 2017 year)


7. Assure yourself of 2017 year deduction if new Tax Reform ACT reduces or eliminates property tax deduction in the 2018 year.



 1. If you are in the Alternative Minimum Tax (AMT) scenario, for the 2017 year, NObenefit will be received from the payment of real estate taxes.


 2. You will lose the use of the cash for a minimum of two months if you reside in Cook County where the first installment of real estate tax is usually due on March 1, 2018. 



Cook County residents can prepay up to 55% of the total amount of their 2017 real estate tax bill. Two steps must be taken in order to make a real estate tax pre-payment in Cook County:


 A. The first step is to contact the Cook County Treasurer's office to request that a Prepayment Program bill be mailed to you. There are three ways to contact the Treasurer's office to enroll in the Prepayment Program (note: all three methods will require you to provide your Property Index Number-PIN):


1.  By email: visit:, click the "payments" button at the top of the website. Click "Prepayment of First Installment Property Taxes" and fill in your information. Be sure that you choose "Prepayment Program" in the subject portion of your message.


2.  By mail: send a note to the address below requesting a PrepaymentProgram bill. Be sure to include your mailing address and PIN in your note.


Cook County Treasurer

Attn: Prepayments

118 N. Clark Street, Room 112

Chicago, Illinois 60602


3.  You can also request a Prepayment Program bill in person at the above address. 


B.  The second step is to make your payment with your Prepayment Program bill to the Cook County Treasurer. Prepayments must be postmarked or delivered no later than December 29, 2017. Include the original tax bill payment coupon. Please send the correct amount. Overages will result in your check being returned. Your check must be made payable to the "Cook County Treasurer"; it should have a December, 2017 date and include the words "Prepayment of 2017 Real Estate Tax" in the memo. Your property index number, phone number and email (if available) should also be included on your check next to your address. You may make your payment in person at any Chase Bank location in the Chicagoland area or mail your payment to:


Cook County Treasurer

P.O. Box 805436

Chicago, Illinois 60680-4155


Phone: (312) 443-5100


If paying by mail, write the word "Prepayment" on the envelope in which the check is enclosed. Note also that no receipts will be mailed back to you. Your cancelled check will serve as your receipt.





C. PAY at Chase Bank Locations


Please also note the following about paying current taxes at Chase Bank:

  • You must present a tax bill payment coupon, such as the one you received in the mail with your tax bill. You may print a duplicate coupon on our website. Printouts from our website of other payment information will not be accepted.

  • Through the dates listed on the bill, you may submit payment using cash, standard checks, money orders, cashier's checks or certified checks drawn on any bank.

  • Partial payments are accepted at Chase Bank.

  • You must submit one original payment coupon and check per PIN.

  • You will receive a dated receipt.



Lake County residents may prepay up to 100% of the amount of their 2017 real estate tax bill. Prepayments will be accepted only during the period from December 15 to December 29, 2017. The balance of the tax will be billed subsequently in the 2018 year.


Make your check payable to the "Lake County Treasurer". The check should have a December, 2017 date; include the words "Prepayment of 2017 Real Estate Tax", your name, address and property index number (PIN) on your check. Your payment and Pre-payment Agreement must be received no later than December 29, 2017 at the following address (no postmarks will be honored):


Lake County Treasurer


18 North County Street, Room 102

Waukegan, Illinois 60085

(847) 377-2323 



McHenry County residents can prepay a deposit of any amount towards 2017 year real estate taxes. You must submit a signed "Pre-Payment Agreement" with your deposit and also include your Property Index Number (PIN). This agreement can be found at McHenry County Treasurer Office Website, click on advance tax button on the left hand side.


The advance deposit DOES NOT automatically pay your bill. The deposit amount will be held until 2017 taxes are issued. At this time you must settle the difference by the first installment due date.


If the entire amount due for the 2017 (both installments) tax bill is not received by the FIRST INSTALLMENT DUE DATE, your entire deposit will be returned. No advanced payment will be accepted after close of business on December 29, 2017. 


In order to submit payment for the deposit or the settlement amount, the check must be payable to "McHenry County Collector." Any checks should include your Property Index Number (PIN), and the words "Prepayment of 2017 Real Estate Tax". Your payment must be received no later than December 30, 2017 at the following address (no postmarks will be honored):


McHenry County Collector

ATTN: Karla / Collen

2200 N. Seminary Avenue

Woodstock, Illinois 60098

(815) 334-4260


If you do not pay the entire amount due by March 28th, 2018 and your deposit is returned to you, your taxes will remain unpaid and treated like any other delinquent tax.



Will County residents can make prepayments of real estate taxes. Any prepayment amount is allowed with a minimum of 50% and a maximum of 110% of the 2017 tax.


The payment should be accompanied by a separate sheet of paper which lists the property index number along with your name, address, telephone number, a note that states this is "Prepayment of 2017 Real Estate Taxes," and a separate check in the amount of $2.00 to cover the service fee. Be sure to include your Property Index Number (PIN) in the memo section of your 2017 prepayment check and to date your check in December, 2017. In order to receive a receipt of prepayment, include a self addressed stamped envelope, or pay in person. Your payment must be received no later than December 29, 2017 at the following address (no postmarks will be honored):


Will County Treasurer Office


302 N. Chicago Street

Joliet, Illinois 60432

(815) 740-4675 



Du Page County residents may prepay up to 105% of the amount of their 2017 realestate tax bill using the Du Page County's Prepayment Plan. You are able to sign up for this Program at - office website, click on paying your real estate taxes / prepayment plan:


When you sign up for this Program, you are able to make as many monthly or periodic payments between December, 2017 and August, 2018. You will choose the amount of your payments (minimum of $100.00).


When you make payments, be sure to include your Property Index Number (PIN) in the memo section of your 2017 prepayment check and include the word "Prepayment" on your check. You can make your payment by mail or in person at the Du Page County Treasurer's Office at the following address:


Du Page County Treasurer

Attn: Prepayment Program

421 N. County Farm Rd.

Wheaton, IL 60187

(630) 407-5900

If further information or analysis is desired, or if you would like information about prepaying real estate taxes in a county not mentioned in this letter, please call your tax professional in our office.


Your trusted advisors,

Schuman Simon & Grodecki Ltd.

Certified Public Accountants

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