65 ILCS 5/11-30-3
In order to promote the public health and safety and the health and safety of the occupants of the premises herein defined, the corporate authorities may license, locate and regulate the use and construction of rooming houses. In municipalities of more than 500,000 inhabitants the fee for any license authorized under this Section shall not exceed the sum of $25 per year.
For the purposes of this section, the term "rooming house" means a building or portion of a building other than a hotel, motel, apartment hotel, or residential hotel, in which sleeping accommodations not constituting an apartment are furnished at a fee for 4 or more persons ordinarily renting such accommodations at a specified rate for a specified time, and occupying the premises as a permanent place of abode rather than on a transient basis for a short term period of occupancy. An apartment is herein defined as a self-contained unit with private bath and cooking facilities.
65 ILCS 5/11-30-3