320 ILCS 25/3.09
"Property taxes accrued" means the ad valorem property taxes extended against a residence, but does not include special assessments, interest or charges for service. In the case of real estate improved with a multidwelling or multipurpose building, "property taxes accrued" extended against a residence within such a building is an amount equal to the same percentage of the total property taxes extended against that real estate as improved as the value of the residence is to the total value of the building. If the multidwelling building is owned and operated as a cooperative, the value of an individual residence is the value of the interest in the cooperative held by the owner of record of the legal or equitable interest, other than a leasehold interest, in the cooperative which confers the right to occupy that residence. In determining the amount of grant under Section 4 , the applicable "property taxes accrued", as determined under this Section, are those payable or paid in the last preceding taxable year.
In addition, if the residence is a mobile home as defined in and subject to the tax imposed by the Mobile Home Local Services Tax Act, "property taxes accrued" includes the amount of privilege tax paid during the calendar year for which benefits are claimed under that Act on that mobile home. If (i) the residence is a mobile home, (ii) the resident is the record owner of the property upon which the mobile home is located, and (iii) the resident is liable for the taxes imposed under the Property Tax Code for both the mobile home and the property, then "property taxes accrued" includes the amount of property taxes paid on both the mobile home and the property upon which the mobile home is located.
320 ILCS 25/3.09