65 ILCS 5/9-2-88
In counties having a population of less than 1,000,000 in all cases, except where land or lots have been withdrawn from collection for want of bidders or forfeited to the State for nonpayment of special assessments 2 or more years in succession next preceding the year in which the application for judgment and order of sale is made, the collector of the municipality shall send a notice of the application for judgment and sale of the land or lots upon which special assessments remain due and unpaid, the date of sale, a description of the land or lots, and the amount of the special assessments together with interest and costs due thereon. The notice shall be sent by mail, either by letter or post card, postage prepaid, at least 5 days before the date of sale. The notice shall be addressed to the person shown by the county collector's current warrant book to be the party in whose name the general real estate taxes on such property were last assessed, and such notices shall be mailed to each such party at the address shown for such party in the county collector's current warrant book. For each such notice the collector of the municipality shall charge an amount equal to the actual costs, not to exceed 0.02% of the assessed value of each parcel, to be taxed and collected as costs.
65 ILCS 5/9-2-88