The Illinois Department of Revenue announced on Mar. 10 that Madison County has been assigned a final property assessment equalization factor, or “multiplier,” of 1.0000 for the 2025 tax year, according to David Harris, director of the department.
The equalization factor is used to ensure uniform property assessments across counties in Illinois, which is important because many local taxing districts overlap county lines. Without this process, taxpayers with similar properties could face unequal tax burdens.
Under state law passed in 1975, most property in Illinois should be assessed at one-third of its market value. In Madison County, assessments are currently at 33.32% of market value based on sales from the past three years. The new multiplier applies to taxes payable in 2026 and matches last year’s figure for the county. The final factor was set after a public hearing and follows a tentative factor issued in December 2025.
Harris said the equalization factor is determined each year by comparing recent sale prices to assessed values placed by local officials. If average assessments match one-third of market value, the multiplier is set at one; if they are higher or lower than this benchmark, the multiplier adjusts accordingly.
A change in the equalization factor does not automatically mean that total property tax bills will rise or fall. Local taxing bodies determine how much money they need each year for services, and if their requests do not increase from previous years, overall taxes remain stable even if assessments change.
The Illinois Department of Revenue works to foster an inclusive environment that values diversity and equity for employees and customers, as stated on its official site. The department also focuses on fairly administering state tax laws and efficiently collecting revenues while providing accurate information according to its official website. It serves as a state agency dedicated to promoting diversity and equity in its operations according to its official site, oversees collection of state taxes and delivers reliable financial information according to its official website, and operates within state taxation and revenue management as detailed on its official website.
