35 ILCS 200/21-375
In counties with less than 3,000,000 inhabitants, when forfeited taxes on a property remain unpaid for one or more years, it is permissible to pay to the county or township collector, one or more full years of back or forfeited taxes, interest prior to forfeiture, statutory costs, printers' fees, and forfeiture interest or penalties, attaching thereto beginning with the earliest year for which the taxes are unpaid. In no case shall payment on account of a designated years' taxes be accepted unless the sums due for prior years have first been paid or are tendered at the same time.
Any person seeking to make payments under this Section shall notify the county clerk of his or her intention in person or by agent or in writing. If notice is given while the collector has possession of the collector's books, the county clerk shall prepare an addendum to be presented to the collector and attached, by the collector, to the collector's books on which the description of the property involved appears, which addendum shall become a part of the collector's books. If notice is given after the tax sale, but before receipt by the county collector of the current collector's books, the county clerk shall prepare an addendum and attach it to the Tax Judgment, Sale, Redemption, and Forfeiture record, on which the property involved appears, which addendum shall become a part of that record.
The addendum shall show separately, for the year or years to be paid, (a) the amount of back or forfeited taxes, (b) interest prior to forfeiture, (c) statutory costs and printers' fees, and (d) forfeiture interest or penalties attaching thereto. The county clerk shall, at the same time, order the county or town collector to receive from the person the amount due on account of the taxes, for the year or years determined as provided above, of the back or forfeited taxes, interest prior to forfeiture, statutory costs, printers' fees, and forfeiture interest or penalties to date attaching to the back or forfeited taxes.
Upon presentation of the order from the county clerk, and receipt of the addendum if the books are in the collector's possession, the collector shall receive the sum tendered on account of the taxes for the year or years designated, and make out duplicate receipts therefor. The receipts shall set forth a description of the property, the year or years paid, and the total amount received. One copy of the receipt shall be given the person making payment and, when countersigned by the county clerk, shall be evidence of the payment therein set forth. The second copy shall be filed by the county clerk in his or her office.
If the collector's books are in the collector's possession, he or she shall enter the payment on the current collector's books or addendum, and he or she shall also enter any unpaid balance on the Tax Judgment, Sale, Redemption and Forfeiture record at the proper time.
After the tax sale and before receipt by the county collector of the current collector's books, the county clerk shall make a proper entry on the Tax Judgment, Sale, Redemption and Forfeiture record, and shall charge the county collector with the sum received. The county clerk shall also enter any unpaid balance on the county collector's books at the proper time.
The county collector shall distribute all sums received as required by law.
35 ILCS 200/21-375