IL HB0598

Amends the Property Tax Code (Sections 18-185 and 21-150) to modify definitions and provisions under the Property Tax Extension Limitation Law (PTELL).

Adds a new exclusion from "aggregate extension" calculations for tax levies made under Section 4 of the Community Mental Health Act to fund community mental health facilities and services, including services for persons with developmental disabilities or substance use disorders.

Expands the list of special purpose extensions excluded from property tax caps to include levies for community mental health facilities across multiple categories of taxing districts (those subject to PTELL before 1995, after 1995, and those opting in via referendum).

Applies to affected counties defined as those with 3,000,000 or more inhabitants (Cook County) or counties contiguous to such counties.