35 ILCS 200/16-160
In counties with 3,000,000 or more inhabitants, beginning with assessments made for the 1996 assessment year for residential property of 6 units or less and beginning with assessments made for the 1997 assessment year for all other property, and for all property in any county other than a county with 3,000,000 or more inhabitants, any taxpayer dissatisfied with the decision of a board of review or board of appeals as such decision pertains to the assessment of his or her property for taxation purposes, or any taxing body that has an interest in the decision of the board of review or board of appeals on an assessment made by any local assessment officer, may, (i) in counties with less than 3,000,000 inhabitants within 30 days after the date of written notice of the decision of the board of review or (ii) in assessment year 1999 and thereafter in counties with 3,000,000 or more inhabitants within 30 days after the date of the board of review notice or within 30 days after the date that the board of review transmits to the county assessor pursuant to Section 16-125 its final action on the township in which the property is located, whichever is later, appeal the decision to the Property Tax Appeal Board for review. In any appeal where the board of review or board of appeals has given written notice of the hearing to the taxpayer 30 days before the hearing, failure to appear at the board of review or board of appeals hearing shall be grounds for dismissal of the appeal unless a continuance is granted to the taxpayer. If an appeal is dismissed for failure to appear at a board of review or board of appeals hearing, the Property Tax Appeal Board shall have no jurisdiction to hear any subsequent appeal on that taxpayer's complaint. Such taxpayer or taxing body, hereinafter called the appellant, shall file a petition with the clerk of the Property Tax Appeal Board, setting forth the facts upon which he or she bases the objection, together with a statement of the contentions of law which he or she desires to raise, and the relief requested. If a petition is filed by a taxpayer, the taxpayer is precluded from filing objections based upon valuation, as may otherwise be permitted by Sections 21-175 and 23-5. However, any taxpayer not satisfied with the decision of the board of review or board of appeals as such decision pertains to the assessment of his or her property need not appeal the decision to the Property Tax Appeal Board before seeking relief in the courts. The changes made by this amendatory Act of the 91st General Assembly shall be effective beginning with the 1999 assessment year.
An association may, on behalf of all or several of the owners that constitute the association, file an appeal to the Property Tax Appeal Board or intervene in an appeal to the Property Tax Appeal Board filed by a taxing body. For purposes of this Section, "association" means: (1) a common interest community association, as that term is defined in Section 1-5 of the Common Interest Community Association Act; (2) a unit owners' association, as that term is defined in subsection (o) of Section 2 of the Condominium Property Act; or (3) a master association, as that term is defined in subsection (u) of Section 2 of the Condominium Property Act.
35 ILCS 200/16-160