35 ILCS 250/20
(a) Any deferral or exemption of payment of an increase in real property taxes granted under this Act shall be limited to real property that meets both of the following conditions:
(2) The property is the principal residence and domicile of the longtime owner-occupant.
The corporate authorities of a county, by ordinance or resolution, may impose additional criteria for qualifying for a deferral or exemption under this Act including, but not limited to, (i) requiring the owner-occupant to have owned and occupied the same dwelling place as principal residence and domicile for a period of more than 10 years, (ii) establishing age criteria for eligibility of an owner-occupant, and (iii) establishing income criteria for eligibility of an owner-occupant. A deferral or exemption, or combination thereof, under an ordinance or resolution adopted pursuant to this Act, may not exceed $20,000 in equalized assessed value per tax year.
(Source: P.A. 93-715, eff. 7-12-04; 94-1074, eff. 12-26-06.)