IL HB1837

Increases the maximum general homestead exemption from $10,000 to $50,000 in counties with 3,000,000 or more inhabitants (Cook County) beginning in tax year 2025

Caps property tax liability for single-family homes and residential dwellings with fewer than 3 units in Cook County at the "adjusted property tax liability" for tax years 2025 through 2027

Defines "adjusted property tax liability" as the 2018 base year tax liability increased by 5% compounded annually through the current tax year

Resets the base year to the year of sale or transfer if a property changes ownership during tax years 2025, 2026, or 2027

Maintains existing exemption levels for other counties: $8,000 for counties contiguous to Cook County and $6,000 for all other counties