35 ILCS 200/22-25
In addition to the notice required to be served not less than one month nor more than 6 months prior to the expiration of the period of redemption, the purchaser or his or her assignee shall prepare and deliver to the clerk of the Circuit Court of the county in which the property is located, not more than 6 months and not less than 3 months prior to the expiration of the period of redemption, the notice provided for in this Section, together with the statutory costs for mailing the notice by certified mail, return receipt requested. The form of notice to be mailed by the clerk shall be identical in form to that provided by Section 22-10 for service upon owners residing upon the property sold, except that it shall bear the signature of the clerk instead of the name of the purchaser or assignee and shall designate the parties to whom it is to be mailed. The clerk may furnish the form. The clerk shall mail the notices delivered to him or her by certified mail, return receipt requested, not less than 3 months prior to the expiration of the period of redemption. The certificate of the clerk that he or she has mailed the notices, together with the return receipts, shall be filed in and made a part of the court record. The notices shall be mailed to the owners of the property at their last known addresses, and to those persons who are entitled to service of notice as occupants.
The changes to this Section made by Public Act 97-557 shall be construed as being declaratory of existing law and not as a new enactment.
The changes to this Section made by Public Act 102-1003 apply to matters in which a petition for tax deed is filed on or after May 27, 2022 (the effective date of Public Act 102-1003) . Failure of any party or any public official to comply with the changes made to this Section by Public Act 102-528 does not invalidate any tax deed issued prior to May 27, 2022 (the effective date of Public Act 102-1003) .
35 ILCS 200/22-25