735 ILCS 5/12-141
Except as to any sale had by virtue of a judgment of foreclosure in accordance with Article XV of this Act, whenever any real estate is sold under any judgment of any court, the holder of the certificate of that sale, may pay all taxes and assessments which are or may become a lien on that real estate during the time of redemption running on the sale. Whenever redemption is made from that sale the party or parties entitled to redeem shall pay to the holder of the certificate of sale, or grantee under such deed, or to the sheriff or other officer who sold the real estate, or his successor in office, in addition to the amount due on the certificate, or deed, the amount paid by the holder thereof or grantee therein for the taxes and assessments, together with interest thereon at the rate of 10% per annum, if before the redemption is made a receipt for those taxes or assessments is filed with the sheriff or other officer who made the sale or exhibited by the holder of the certificate if redemption is made directly to the holder of the certificate, or the grantee in such deed.
735 ILCS 5/12-141