Cook County property taxes have grown twice the rate of inflation over the past three decades, forcing home and business owners to turn over an ever-greater percentage of their annual earnings to local governments, according to a study released Monday by Treasurer Maria Pappas. During those 30 years, property taxes imposed in Cook County grew by 182 percent to $19.2 billion, while inflation rose by less than 91 percent and average wages grew by 161 percent. The study notes that the Illinois Department of Revenue is working on a comprehensive property tax report and suggests now is the time for Illinois lawmakers to pass significant tax reform and find ways for local taxing agencies to cut spending.

Property taxes skyrocketed despite a state law designed to limit tax increases, primarily because government leaders have exploited loopholes in the law. Key among those loopholes is placing no limits on property tax increases in special taxing districts, where a portion of property tax money is set aside to subsidize private development and job creation. Taxes in those tax increment finance districts, which have dramatically multiplied over the years, grew more than 1,000 percent, exceeding $1.8 billion in tax year 2024.

Also driving up taxes faster than inflation, and wage growth, was a 189% increase in taxes imposed by K-12 school districts that far outstripped the 91 percent inflation rate. School districts levied more than $10.5 billion in taxes in 2024, accounting for nearly 55% of the total county property tax burden. The study, “How State Laws Failed to Stop Decades of Skyrocketing Property Taxes: A Case for Reform,” notes that state legislators have long been aware of the unsustainable upward trajectory in property taxes, but despite producing a slew of studies and legislative initiatives, have failed to provide relief for businesses and homeowners. In some cases, state government made the problem worse by enhancing local government pension benefits and lowering the share of state revenue passed along to cities and villages, whose taxes increased by 201% over the 30-year period.