Are utilities considered part of rent in Illinois?

It depends on the lease. If the Illinois lease bundles utilities into the monthly rent (one combined number, paid to the landlord), they are part of rent for purposes of the rent cap, the deposit cap, and rent increase notice. If the lease separates them (tenant pays the utility company directly, or pays a separate utility allowance to the landlord), they are usually NOT part of rent. Illinois has no statewide advance notice specific to rent increases. 735 ILCS 5/9-207 sets 30 days as the month-to-month termination default, which landlords treat as the minimum for rent changes. No state rent cap; local rent control is preempted statewide. A landlord who shifts utilities from "included" to "tenant pays" mid-tenancy without proper notice is effectively raising rent and must comply with the rent increase notice rules. Some Illinois jurisdictions also require RUBS (ratio utility billing system) or sub-metering disclosures before splitting utilities. The key question: does the change increase the tenant's net monthly out-of-pocket cost? If yes, treat it as a rent increase.

Source: Lease-based; 735 ILCS 5/9-207 (30-day month-to-month termination default)